Preoperative giant sacrococcygeal teratoma embolization in a newborn - A case report and a review. / Embolización preoperatoria de teratoma sacrococcigéo gigante en un recién nacido. Reporte de un caso y revisión.

Sacrococcygeal teratoma (SCT) is the most frequent congenital germ cell tumor. Patients have a higher risk of perinatal complications and death, with bleeding and cardiac decompensation being the most common causes of neonatal mortality. This is the case of a 35-week preterm newborn with a large SCT diagnosed at ultrasound screening in the second trimester. Preoperative selective embolization of the middle sacral artery and total surgical resection were performed postnatally with minimal blood loss. The patient was discharged at 25 days of life with a normal physical examination. Selective embolization prior to giant SCT resection is feasible and appears as a safe and useful technique in the control of perioperative bleeding.

El teratoma sacrococcígeo (TSC) es el tumor congénito de células germinales más frecuente. Los pacientes afectados tienen un mayor riesgo de complicaciones perinatales y muerte, siendo la hemorragia y la descompensación cardiaca las causas más comunes de mortalidad neonatal. Presentamos el caso de un recién nacido pretérmino de 35 semanas con un TSC de gran tamaño diagnosticado por ecografía en el segundo trimestre. La embolización selectiva preoperatoria de la arteria sacra media y la resección quirúrgica total postnatal se realizaron con una mínima pérdida de sangre. El paciente fue dado de alta a los 25 días de vida con un examen físico normal. La embolización selectiva antes de la cirugía de resección del TSC gigante es factible y aparece como una técnica segura y útil en el control del sangrado perioperatorio.

Silver nanoparticle embedded copper oxide as an efficient core-shell for the catalytic reduction of 4-nitrophenol and antibacterial activity improvement.

A facile and eco-friendly method was developed to prepare a microporous CuO@Ag0 core-shell with high catalytic and antibacterial activities. Scanning and transmission electron microscopy revealed a preponderance of nearly spherical 50 nm particles with slight structure compaction. Comparison of the hysteresis loops confirmed the structure compaction after AgNP incorporation, and a significant decrease of the specific surface area from 55.31 m2 g-1 for CuO to 8.03 m2 g-1 for CuO@Ag0 was noticed. A kinetic study of 4-nitrophenol (4-NP) reduction into 4-aminophenol (4-AP) with sodium borohydride revealed a first order reaction that produces total conversion in less than 18 minutes. CuO@Ag0 also exhibited appreciable antibacterial activity against Staphylococcus aureus. The antibacterial effects were found to strongly depend on the size, contact surface, morphology and chemical composition of the catalyst particles. The addition of Ag0-NPs produced more reactive oxygen species in the bacteria medium. These results open promising prospects for its potential applications as a low cost catalyst in wastewater treatment and antibacterial agent in cosmetics.

Exploring uptake and biodistribution of polystyrene (nano)particles in zebrafish embryos at different developmental stages.

In ecotoxicology, it is continuously questioned whether (nano)particle exposure results in particle uptake and subsequent biodistribution or if particles adsorb to the epithelial layer only. To contribute to answering this question, we investigated different uptake routes in zebrafish embryos and how they affect particle uptake into organs and within whole organisms. This is addressed by exposing three different life stages of the zebrafish embryo in order to cover the following exposure routes: via chorion and dermal exposure; dermal exposure; oral and dermal exposure. How different nanoparticle sizes affect uptake routes was assessed by using polystyrene particles of 25, 50, 250 and 700nm. In our experimental study, we showed that particle uptake in biota is restricted to oral exposure, whereas the dermal route resulted in adsorption to the epidermis and gills only. Ingestion followed by biodistribution was observed for the tested particles of 25 and 50nm. The particles spread through the body and eventually accumulated in specific organs and tissues such as the eyes. Particles larger than 50nm were predominantly adsorbed onto the intestinal tract and outer epidermis of zebrafish embryos. Embryos exposed to particles via both epidermis and intestine showed highest uptake and eventually accumulated particles in the eye, whereas uptake of particles via the chorion and epidermis resulted in marginal uptake. Organ uptake and internal distribution should be monitored more closely to provide more in depth information of the toxicity of particles.

Differences during the first lactation between cows cloned by somatic cell nuclear transfer and noncloned cows.

Lactation performance is dependent on both the genetic characteristics and the environmental conditions surrounding lactating cows. However, individual variations can still be observed within a given breed under similar environmental conditions. The role of the environment between birth and lactation could be better appreciated in cloned cows, which are presumed to be genetically identical, but differences in lactation performance between cloned and noncloned cows first need to be clearly evaluated. Conflicting results have been described in the literature, so our aim was to clarify this situation. Nine cloned Prim' Holstein cows were produced by the transfer of nuclei from a single fibroblast cell line after cell fusion with enucleated oocytes. The cloned cows and 9 noncloned counterparts were raised under similar conditions. Milk production and composition were recorded monthly from calving until 200d in milk. At 67d in milk, biopsies were sampled from the rear quarter of the udder, their mammary epithelial cell content was evaluated, and mammary cell renewal, RNA, and DNA were then analyzed in relevant samples. The results showed that milk production did not differ significantly between cloned and noncloned cows, but milk protein and fat contents were less variable in cloned cows. Furthermore, milk fat yield and contents were lower in cloned cows during early lactation. At around 67 DIM, milk fat and protein yields, as well as milk fat, protein, and lactose contents, were also lower in cloned cows. These lower yields could be linked to the higher apoptotic rate observed in cloned cows. Apoptosis is triggered by insulin-like factor growth binding protein 5 (IGFBP5) and plasminogen activator inhibitor (PAI), which both interact with CSN1S2. During our experiments, CSN1S2 transcript levels were lower in the mammary gland of cloned cows. The mammary cell apoptotic rate observed in cloned cows may have been related to the higher levels of DNA (cytosine-5-)-methyltransferase 1 (DNMT1) transcripts, coding for products that maintain the epigenetic status of cells. We conclude, therefore, that milk production in cloned cows differs slightly from that of noncloned cows. These differences may be due, in part, to a higher incidence of subclinical mastitis. They were associated with differences in cell apoptosis and linked to variations in DNMT1 mRNA. However, milk protein and fat contents were more similar among cloned cows than among noncloned cows.

A wireless system with stimulation and recording capabilities for interfacing peripheral nerves in rodents.

Considerable progress has been made in the last decade in implantable bioelectronic neurosystems. Yet most neural implants are used in acute and tethered experimental conditions. Here, we present a preliminary prototype of a multichannel system for simultaneous peripheral nerve stimulation and neural recording. The system comprises miniaturized electronics with a total volume of less then 1.4cm3 including a 3.7V battery which is expected to last for 94 days of standby operation or 18 hours of continuous recording and stimulation. Data read-out and device configuration are wireless. Visceral nerves in rodents are interfaced with compliant extraneural electrodes. The 100×350µm2 electrodes display a low impedance (1.8kn at 1kHz) with a PEDOT:PSS coating. We validated the prototype in acute experiments by applying electrical stimulation to the aortic depressor nerve (ADN), resulting in effective and reproducible decrease in blood pressure and heart rate. The combination of miniaturized electronics and flexible electrodes makes the presented system a versatile platform for future implantable devices interfacing small peripheral nerves and potentially enables new applications in the field of neuroscience.

Reproductive response in offspring male rats exposed to prenatal stress and to early postnatal stimulation / Respuestas reproductivas en ratas estresadas prenatalmente, expuestas a estimulación postnatal

Stress in pregnant rats alters the pattern of secretion of corticosterone (COR) and modifies transplacentally hypothalamic-pituitary-adrenal axis (HPA) fetus. Prenatal stress during the critical hypothalamic differentiation is related to decreased fertility of male offspring by an increase in the basal level of COR. This modification could induce long-term changes in the process of apoptosis in the testis. However, early postnatal handling increases maternal behavior and could reverse the effects caused by increased secretion of COR. The aim of this research was to investigate the effects of early postnatal stimulation of male rats prenatal stressed by chronic immobilization during the last two weeks of pregnancy, on the hypothalamic-pituitary-gonadal axis and their relationship with the activity of the HPA. Male Wistar rats 3 month olds, were separated in four groups: (a) prenatally stressed animals by immobilization (IMO), without postnatal stimulation; (b) prenatally stressed animals with postnatal stimulation; (c) control animals without prenatal stress, without postnatal stimulation and (d) control animals without prenatal stress, with postnatal stimulation. In different animals groups plasmatic levels of COR, Testosterone (T) and Luteinizing Hormone (LH) were analyzed. Gonadosomatic index and testicular apoptosis was determined. In conclusion that prenatal stress by IMO increased levels of COR and inhibits the HHG axis obtaining low values of plasmatic LH and T, testicular weight, and induction of apoptosis in testes. On other hand, early postnatal stimulation results in an increase in maternal care to the offspring reversing the effects of prenatal stress on the HPG axis. This effect could be mediated by a mechanism independent of the HPA axis.

El estrés en ratas preñadas altera el patrón de secreción de corticosterona (COR) materna la cual, por vía transplacentaria, produce una alteración del eje Hipotálamo-Hipófiso-Adrenal (HHA) fetal. El estrés prenatal producido durante la etapa crítica de diferenciación hipotalámica, está relacionado con la disminución de la fertilidad en las crías macho, por un aumento en el nivel de COR basal. Esta modificación podría inducir cambios a largo plazo en el proceso de apoptosis testicular. Sin embargo, la estimulación postnatal temprana mejora el comportamiento materno, revirtiendo las alteraciones producidas por el aumento de COR en las crías adultas. El objetivo fue investigar el efecto de la estimulación postnatal temprana sobre el eje Hipotálamo-Hipófiso-Gonadal (HHG) en ratas macho estresadas prenatalmente (EP), por inmovilización crónica durante las dos últimas semanas de la preñez. Se utilizaron crías de 3 meses de edad, que fueron divididas en 4 grupos: (a) individuos EP y sin estimulación postnatal; (b) individuos EP con estimulación postnatal; (c) individuos controles no estresados prenatalmente (CP) y sin estimulación postnatal; y (d) individuos CP con estimulación postnatal. En todos los grupos se midió COR, Testosterona (T) y Hormona Luteinizante (LH). Se determinaron la apoptosis y la Caspasa 3 testicular y el índice gonadosomático. Se concluye que el estrés prenatal por inmovilización aumenta los niveles de COR del eje HHA e inhibe el eje HHG obteniendo valores bajos de LH y T plasmáticas. Se observa disminución del tamaño testicular y aumento de la apoptosis de las células testiculares. Por otro lado, la estimulación postnatal temprana se traduce en un aumento del cuidado materno hacia la cría, lo que revierte los efectos producidos por el estrés prenatal sobre el eje HHG. Este efecto podría estar mediado por algún mecanismo independiente del eje HHA.

[Pediatric surgery 2.0]. / Cirugía pediátrica 2.0.

New tools from the web are a complete breakthrough in management of information. The aim of this paper is to present different resources in a friendly way, with apps and examples in the different phases of the knowledge management for the paediatric surgeon: search, filter, reception, classification, sharing, collaborative work and publication. We are assisting to a real revolution on how to manage knowledge and information. The main charateristics are: immediateness, social component, growing interaction, and easiness. Every physician has clinical questions and the Internet gives us more and more resources to make searchs easier. Along with them we need electronic resources to filter information of quality and to make easier transfer of knowledge to clinical practice. Cloud computing is on continuous development and makes possible sharing information with differents users and computers. The main feature of the apps from the Intenet is the social component, that makes possible interaction, sharing and collaborative work.

[Long term follow-up of bile duct stenosis treated with interventional radiology in pediatric liver transplantation]. / Seguimiento a largo plazo de las estenosis de la vía biliar tratadas con radiología intervencionista en el trasplante hepático pediátrico.

The reported incidence of biliary strictures following pediatric liver transplantation has ranged between 5-34%, with a higher incidence in segmental grafts. Currently, percutaneous transhepatic balloon dilatation of biliary strictures is considered as the first line treatment owing to its minimal invasiveness. Between 1995-2006, 20 children who underwent liver transplantation developed biliary complications treated with interventional radiology. 16/20 developed biliary stricture, of whom 10 were treated with percutaneous transhepatic balloon dilatation. The mean age at the procedure was 6.6 years (range 8 m--14 years). The allograft types included whole (n=4), split (n=3), and reduced (n=3) livers. The procedure was performed at a mean time post-transplantation of 2.6 years. All patients are alive with a mean follow-up post-procedure of 24 months (range: 4 months-11 years). Currently, only 4 have a normal appearing biliary tree by imaging techniques and 6 developed stricture recurrence; of whom 3 developed biliary cirrhosis (2 splits, 1 reduced), one patient underwent successful rescue surgery, one was treated again percutaneously, and the remaining was lost to followup. In conclusion, treatment of percutaneous transhepatic balloon dilatation of biliary strictures is effective avoiding surgical correction. However, stricture recurrence in the medium- long term follow-up is frequent, particularly in segmental grafts. [corrected]

Manifold aspects of specificity in a nematode-bacterium mutualism.

Coevolution in mutualistic symbiosis can yield, because the interacting partners share common interests, to coadaptation: hosts perform better when associated with symbionts of their own locality than with others coming from more distant places. However, as the two partners of a symbiosis might also experience conflicts over part of their life cycle, coadaptation might not occur for all life-history traits. We investigated this issue in symbiotic systems where nematodes (Steinernema) and bacteria (Xenorhabdus) reproduce in insects they have both contributed to kill. Newborn infective juveniles (IJs) that carry bacteria in their intestine then disperse from the insect cadaver in search of a new host to infect. We ran experiments where nematodes coinfect insects with bacteria that differ from their native symbiont. In both Steinernema carpocapsae/Xenorhabdus nematophila and Steinernema feltiae/Xenorhabdus bovienii symbioses, we detected an overall specificity which favours the hypothesis of a fine-tuned co-adaptation process. However, we also found that the life-history traits involved in specificity strongly differ between the two model systems: when associated with strains that differ too much from their native symbionts, S. carpocapsae has low parasitic success, whereas S. feltiae has low survival in dispersal stage.

Multi-dimensional and multi-signal approaches in scanning transmission electron microscopes.

Developments in instrumentation are essential to open new fields of science. This clearly applies to electron microscopy, where recent progress in all hardware components and in digitally assisted data acquisition and processing has radically extended the domains of application. The demonstrated breakthroughs in electron optics, such as the successful design and practical realization and the use of correctors, filters and monochromators, and the permanent progress in detector efficiency have pushed forward the performance limits, in terms of spatial resolution in imaging, as well as for energy resolution in electron energy-loss spectroscopy (EELS) and for sensitivity to the identification of single atoms. As a consequence, the objects of the nanoworld, of natural or artificial origin, can now be explored at the ultimate atomic level. The improved energy resolution in EELS, which now encompasses the near-IR/visible/UV spectral domain, also broadens the range of available information, thus providing a powerful tool for the development of nanometre-level photonics. Furthermore, spherical aberration correctors offer an enlarged gap in the objective lens to accommodate nanolaboratory-type devices, while maintaining angström-level resolution for general characterization of the nano-object under study.

[Rehbein's procedure versus De la Torre in Hirschsprung's disease]. / Rehbein versus De la Torre en la enfermedad de Hirschsprung.

The authors perform a retrospective study with a 4 years follow up of 46 patients operated of Hirschsprung's disease (HD). In 36 cases by with staplers Rehbein technique (TR) and in 10 others with De la Torre endorectal pull-through (TEPT). In all them diagnosis was achieved by mean of radiology, manometry, and hystochemical procedures. During the surgical procedure was performed in all cases biopsies to confirm the neuronal integrity of the colon descended. In the TR group, 16.6% of patients presented rectal achalasia with constipation due to 3 cms. aganglionic rectum remnant, while in the TEPT group this circumstance are not presented because all aganglionic rectum was eliminated. Otherwise TEPT technique permits an earlier application, diminuend the hospitalization time,shortening the start of feeding and with a good cosmetic result. None of this patients presented infection, stenosis, bleeding or incontinence.

Hematoma growth is a determinant of mortality and poor outcome after intracerebral hemorrhage.

BACKGROUND: Although volume of intracerebral hemorrhage (ICH) is a predictor of mortality, it is unknown whether subsequent hematoma growth further increases the risk of death or poor functional outcome. METHODS: To determine if hematoma growth independently predicts poor outcome, the authors performed an individual meta-analysis of patients with spontaneous ICH who had CT within 3 hours of onset and 24-hour follow-up. Placebo patients were pooled from three trials investigating dosing, safety, and efficacy of rFVIIa (n = 115), and 103 patients from the Cincinnati study (total 218). Other baseline factors included age, gender, blood glucose, blood pressure, Glasgow Coma Score (GCS), intraventricular hemorrhage (IVH), and location. RESULTS: Overall, 72.9% of patients exhibited some degree of hematoma growth. Percentage hematoma growth (hazard ratio [HR] 1.05 per 10% increase [95% CI: 1.03, 1.08; p < 0.0001]), initial ICH volume (HR 1.01 per mL [95% CI: 1.00, 1.02; p = 0.003]), GCS (HR 0.88 [95% CI: 0.81, 0.96; p = 0.003]), and IVH (HR 2.23 [95% CI: 1.25, 3.98; p = 0.007]) were all associated with increased mortality. Percentage growth (cumulative OR 0.84 [95% CI: 0.75, 0.92; p < 0.0001]), initial ICH volume (cumulative OR 0.94 [95% CI: 0.91, 0.97; p < 0.0001]), GCS (cumulative OR 1.46 [95% CI: 1.21, 1.82; p < 0.0001]), and age (cumulative OR 0.95 [95% CI: 0.92, 0.98; p = 0.0009]) predicted outcome modified Rankin Scale. Gender, location, blood glucose, and blood pressure did not predict outcomes. CONCLUSIONS: Hematoma growth is an independent determinant of both mortality and functional outcome after intracerebral hemorrhage. Attenuation of growth is an important therapeutic strategy.

Radiologic estimation of hematoma volume in intracerebral hemorrhage trial by CT scan.

BACKGROUND AND PURPOSE: Therapeutic intervention during the early stages of an intracerebral hemorrhage (ICH) might have value in improving clinical outcomes. During the 73-site International Recombinant Activated Factor VII Intracerebral Hemorrhage Trial, CT techniques were used to monitor the change in hematoma volume in response to treatment. The use of CT imaging technology served 3 functions: to provide accurate measurements of the change in hematoma volume, intraventricular volume (IVH), and edema volume; to evaluate the use of CT scans as a predictor of patient outcomes; and to demonstrate that hematoma volume can serve as a surrogate marker for ICH clinical progression. METHODS: The multicenter clinical trial received institutional review board approval and obtained informed consent from the patient or a legally acceptable representative (waived in a few cases of incapacity, according to local and national regulations). CT scans were used to quantify volumes of hemorrhage and to monitor evolution over a 72-hour period in patients with ICH treated with placebo or 40, 80, or 160 microg/kg of recombinant activated factor VII (rFVIIa). CT image data were transmitted digitally to an imaging laboratory and analyzed by 2 readers masked to patient and treatment data, by using Analyze software, a fully integrated toolkit for interactive display, processing, and measurement of biomedical image data. The use of this software enabled the evaluation of intraclass variability of CT scan interpretations. RESULTS: Interpretations of ICH and IVH volumes of CT scans in patients treated in this study showed minimal intraclass variability. Variability was greatest for interpretations of edema volume. CONCLUSION: These CT assessments of lesions could have value in future early hemostatic interventions in ICH patients.

The role of ResA in type II cytochrome c maturation.

Numerous bacterial proteins involved in the nitrogen cycle, and other processes, require c-type haem as a cofactor. c-type cytochromes are formed by covalent attachment of haem to the conserved CXXCH motif. Here, we briefly review what is presently known about cytochrome c maturation in Bacillus subtilis with particular emphasis on the crystal structures of ResA.

When mutualists are pathogens: an experimental study of the symbioses between Steinernema (entomopathogenic nematodes) and Xenorhabdus (bacteria).

In this paper, we investigate the level of specialization of the symbiotic association between an entomopathogenic nematode (Steinernema carpocapsae) and its mutualistic native bacterium (Xenorhabdus nematophila). We made experimental combinations on an insect host where nematodes were associated with non-native symbionts belonging to the same species as the native symbiont, to the same genus or even to a different genus of bacteria. All non-native strains are mutualistically associated with congeneric entomopathogenic nematode species in nature. We show that some of the non-native bacterial strains are pathogenic for S. carpocapsae. When the phylogenetic relationships between the bacterial strains was evaluated, we found a clear negative correlation between the effect a bacterium has on nematode fitness and its phylogenetic distance to the native bacteria of this nematode. Moreover, only symbionts that were phylogenetically closely related to the native bacterial strain were transmitted. These results suggest that co-evolution between the partners has led to a high level of specialization in this mutualism, which effectively prevents horizontal transmission. The pathogenicity of some non-native bacterial strains against S. carpocapsae could result from the incapacity of the nematode to resist specific virulence factors produced by these bacteria.

Trajectory of nucleosomal linker DNA studied by fluorescence resonance energy transfer.

While the structure of the nucleosome core is known in atomic detail, the precise geometry of the DNA beyond the core particle is still unknown. We have used fluorescence resonance energy transfer (FRET) for determining the end-to-end distance of DNA fragments assembled with histones into nucleosomes. The DNA of a length of 150-220 bp was labeled with rhodamine-X on one end and fluorescein or Alexa 488 on the other. Assembling nucleosomes on these DNA fragments leads to a measurable energy transfer. The end-to-end distance computed from the FRET increases from 60 +/- 5 A at 150 bp to 75 +/- 5 A at 170 bp without measurable change above it. These distances are compatible with different geometries of the linker DNA, all having in common that no crossing can be observed up to 220 bp. Addition of H1 histone leads to an increase in energy transfer, indicating a compaction of the linker DNA toward the nucleosome.

Determinants of lipid level variability in French-Canadian children with familial hypercholesterolemia.

The wide variability in the biochemical expression of familial hypercholesterolemia (FH) is only partly explained by mutational heterogeneity in the low density lipoprotein receptor (LDLR) gene. In the current study, we measured this biochemical variability in a group of children heterozygous for the >15-kb LDLR gene deletion (n=67) and examined the contribution of apolipoprotein (apo) E and B allelic variations to this phenotypic variability. Variances of total cholesterol (TC), LDL-C, and apoB concentrations and of the ratio of TC to high density lipoprotein cholesterol (HDL-C) were increased in FH subjects compared with controls. However, after taking the means into account, the coefficients of variation showed that the variability of LDL-C and apoB concentrations was smaller for FH than for controls and that the variability of TC and of the ratio TC to HDL-C was similar between both groups. The epsilon2/3 genotype was associated with lower mean TC, LDL-C, and apoB concentrations in FH. The magnitude of this effect was smaller in controls than in FH. Indeed, the percentages of total variance of TC, LDL-C, and apoB attributable to the apoE locus were 19.9%, 18.1%, and 11.8%, respectively, in FH cases and 5.9%, 7.4%, and 6.0%, respectively, in controls. We did not detect any effect of the apoB insertion/deletion polymorphism on lipid traits in FH children. However, in controls, we observed a strong interaction between apoE and apoB genotypes on apoB concentrations and on TC to HDL-C ratios. Our study reemphasizes the important role of apoE in lipid metabolism and illustrates that the effects of allelic variations on lipid traits are context dependent.

Rotational dynamics of curved DNA fragments studied by fluorescence polarization anisotropy.

The rotational dynamics of short DNA fragments with or without intrinsic curvature were studied using time-resolved phase fluorimetry of intercalated ethidium with detection of the anisotropy. Parameters determined were the spinning diffusion coefficient of the DNA fragments about the long axis and the zero-time ethidium fluorescence anisotropy. We find a significant decrease in the spinning diffusion coefficient for all curved fragments compared to the straight controls. This decrease is likewise evident in rotational diffusion coefficients computed from DNA structures obtained by a curvature prediction program for these sequences. Using a hinged-cylinder model, we can identify the change in rotational diffusion coefficient with a permanent bend of 13-16 degrees per helix turn for the sequences studied. Moreover, for some of the curved fragments an increased flexibility has to be assumed in addition to the permanent bend in order to explain the data.