Relationship between cyberbullying and health-related quality of life in a sample of children and adolescents.

PURPOSE: Health-related quality of life (HRQoL) is a well-known construct that refers to a state of complete physical, mental, and social well-being. Its relationship with multiple forms of violence, including bullying, has been widely explored, but this is not the case for cyberbullying. The main objective is to analyze how HRQoL varies depending on the role played in cyberbullying, its temporal stability, and gender and age differences. METHOD: An analytical and longitudinal study was conducted at two temporal moments. At Time 1 (December 2015), 920 Spanish students aged between 11 and 18 years participated (Mage = 13.36, SD = 1.83: 48.9% boys and 51.1% girls). At Time 2 (April 2016), there were 313 participants (Mage 12.81 years, SD = 1.59: 53.4% boys and 46.6% girls). We used the Cyberbullying Test (technological scale) and the Spanish version of the KIDSCREEN-52. RESULTS: Cybervictims and cyberbully-victims present worse scores in all dimensions of the KIDSCREEN-52 (p < .001), compared to cyberbystanders or uninvolved individuals. There are gender differences only in cyberaggression and cyberbystanding. There are significant inverse correlations between all the dimensions of the KIDSCREEN-52 and cybervictimization, with Bullying (r = - .603, p < .001), Mood (r = - .329, p < .001), and School environment (r = - .327, p < .001) being particularly relevant. There were statistically significant differences between T1 and T2 for cyberbystanding (lower scores at T2). CONCLUSION: Cybervictims and cyberbully-victims have worse quality of life in all the dimensions than uninvolved individuals, especially in Psychological well-being, School environment, and Bullying.

Quantification of fluorescent dyes in organ tissue samples via HPLC analysis.

The determination of regional blood flow via the accumulation of fluorescent microspheres is a concept regularly used in medical research. Typically, the microbeads get extracted from the tissue of interest and are then quantified by measuring the absorption or fluorescence of the incorporated dyes without further separation from the medium. However, in that case the absorption spectra of different dyes can overlap when used simultaneously, leading to an overestimation of the concentration. Additionally, background absorption from the medium can be problematic. Therefore, a high performance liquid chromatography method for the simultaneous detection of four dyes (orange, crimson, yellow-green and red) incorporated in different microbeads in samples from biological media such as organ tissue (brain, heart and kidneys) was developed. Since for biological samples often a large sample size is required for sufficient statistics, the method was optimized to yield very short run times. With this method it was possible to detect very low concentrations of only one microsphere per gram of organ tissue. By applying this sensitive quantification technique, it was demonstrated that the application of microbeads for perfusion measurements might not be reliable due to different organ distributions in each animal.

Comparison of seven structurally related coumarins on the inhibition of Quorum sensing of Pseudomonas aeruginosa and Chromobacterium violaceum.

Quorum sensing (QS) is a cell-to-cell signaling communication system that controls the virulence behavior of a broad spectrum of bacterial pathogens, participating also in the development of biofilms, responsible of the antibiotic ineffectiveness in many infections. Therefore, QS system is an attractive target for antimicrobial therapy. In this study, we compare the effect of seven structurally related coumarins against bacterial growth, biofilm formation and elastase activity of Pseudomonas aeruginosa. In addition, the anti-pathogenic capacity of the seven coumarins was evaluated on the wild type and the biosensor strain of Chromobacterium violaceum. The comparative study of coumarins showed that molecules with hydroxyl groups on the aromatic ring displayed higher activity on the inhibition of biofilm formation of P. aeruginosa over coumarins with substituents in positions 3 and 4 or without the double 3,4-bond. These 3 or 4-hydroxylated positions caused a decrease in the anti-biofilm activity obtained for coumarin. However, the hydroxyl group in position 3 of the pyrone ring was important for the inhibition of C. violaceum QS and elastolytic activity of P. aeruginosa. The effects observed were active independently of any effect on growth. According to our results, coumarin and its hydroxylated derivatives represent an interesting group of compounds to use as anti-virulence agents against the human pathogen P. aeruginosa.

Pulmonary effects of expiratory-assisted small-lumen ventilation during upper airway obstruction in pigs.

Novel devices for small-lumen ventilation may enable effective inspiration and expiratory ventilation assistance despite airway obstruction. In this study, we investigated a porcine model of complete upper airway obstruction. After ethical approval, we randomly assigned 13 anaesthetised pigs either to small-lumen ventilation following airway obstruction (n = 8) for 30 min, or to volume-controlled ventilation (sham setting, n = 5). Small-lumen ventilation enabled adequate gas exchange over 30 min. One animal died as a result of a tension pneumothorax in this setting. Redistribution of ventilation from dorsal to central compartments and significant impairment of the distribution of ventilation/perfusion occurred. Histopathology demonstrated considerable lung injury, predominantly through differences in the dorsal dependent lung regions. Small-lumen ventilation maintained adequate gas exchange in a porcine airway obstruction model. The use of this technique for 30 min by inexperienced clinicians was associated with considerable end-expiratory collapse leading to lung injury, and may also carry the risk of severe injury.

Sesqui- and triterpenoids from the liverwort Lepidozia chordulifera inhibitors of bacterial biofilm and elastase activity of human pathogenic bacteria.

Five dammarane-type triterpenoids, five pentacyclic triterpenoids (three of them carrying a carboxylic acid group), and two aromadendrane-type sesquiterpenoids were isolated from an Argentinian collection of the liverwort Lepidozia chordulifera. Compounds were characterized by comparison of their spectral data with those previously reported and tested in their ability to control bacterial growth, biofilm formation, bacterial Quorum Sensing process (QS), and elastase activity of Pseudomonas aeruginosa, as well as bacterial growth and biofilm formation of Staphylococcus aureus. The key role played by biofilm and elastase activity in bacterial virulence make them a potential target for the development of antibacterial agents. The aromadendrane-type sesquiterpenoid viridiflorol was the most potent biofilm formation inhibitor, producing 60% inhibition in P. aeruginosa and 40% in S. aureus at 50µg/ml. Ursolic and betulinic acids (two of the pentacyclic triterpenoids isolated) were able to reduce 96 and 92% the elastase activity of P. aeruginosa at 50µg/ml, respectively. Among the analyzed triterpenoids, those that carry a dammarane skeleton were the most potent inhibitors of the P. aeruginosa biofilm formation and were active against both P. aeruginosa and S. aureus. Subsequently, a computer-assisted study of the triterpenoid compounds was carried out for a better understanding of the structure-activity relationships.

Observation of the Leggett-Rice effect in a unitary Fermi gas.

We observe that the diffusive spin current in a strongly interacting degenerate Fermi gas of (40)K precesses about the local magnetization. As predicted by Leggett and Rice, precession is observed both in the Ramsey phase of a spin-echo sequence, and in the nonlinearity of the magnetization decay. At unitarity, we measure a Leggett-Rice parameter γ=1.08(9) and a bare transverse spin diffusivity D(0)(⊥)=2.3(4)ℏ/m for a normal-state gas initialized with full polarization and at one-fifth of the Fermi temperature, where m is the atomic mass. One might expect γ=0 at unitarity, where two-body scattering is purely dissipative. We observe γ→0 as temperature is increased towards the Fermi temperature, consistent with calculations that show the degenerate Fermi sea restores a nonzero γ. Tuning the scattering length a, we find that a sign change in γ occurs in the range 0<(k(F)a)(-1)≲1.3, where k(F) is the Fermi momentum. We discuss how γ reveals the effective interaction strength of the gas, such that the sign change in γ indicates a switching of branch between a repulsive and an attractive Fermi gas.

Transverse demagnetization dynamics of a unitary Fermi gas.

Understanding the quantum dynamics of strongly interacting fermions is a problem relevant to diverse forms of matter, including high-temperature superconductors, neutron stars, and quark-gluon plasma. An appealing benchmark is offered by cold atomic gases in the unitary limit of strong interactions. Here, we study the dynamics of a transversely magnetized unitary Fermi gas in an inhomogeneous magnetic field. We observe the demagnetization of the gas, caused by diffusive spin transport. At low temperatures, the diffusion constant saturates to the conjectured quantum-mechanical lower bound ≃ h/m, where m is the particle mass. The development of pair correlations, indicating the transformation of the initially noninteracting gas toward a unitary spin mixture, is observed by measuring Tan's contact parameter.

Toxicity of Porella chilensis sesqui- and diterpenoids against larvae of the corn pest Spodoptera frugiperda (J.E. Smith) (Lepidotera: Noctuidae).

Porella, the largest genus of the family Porellaceae (Hepaticae) is widespread in the tropical and subtropical regions of South America. Most Porella species are rich sources of sesqui- and diterpenoids, many of which show interesting biological activities. Secondary metabolites produced by plants can interact with insects and act as antifeedants and growth regulators affecting hormone and nervous systems as well as stomach and muscle tissues. A previous chemical investigation of a Patagonian collection of Porella chilensis yielded sesqui- and diterpenoids that were now evaluated for their effects against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), a serious pest affecting corn crops mainly in the Americas. Four pinguisanes (1-4), three fusicoccanes (5-7), and one aromadendrane (8) from P. chilensis displayed larvicidal activity against S. frugiperda when incorporated to the larval diet at 100 and 200 µg/g of diet with a significant decrease in the larval growing rate. The observed effects were in part produced by severe alterations of the epithelial cells of the midgut as indicated by our histological studies.

Dynamics of a tunable superfluid junction.

We study the population dynamics of a Bose-Einstein condensate in a double-well potential throughout the crossover from Josephson dynamics to hydrodynamics. At barriers higher than the chemical potential, we observe slow oscillations well described by a Josephson model. In the limit of low barriers, the fundamental frequency agrees with a simple hydrodynamic model, but we also observe a second, higher frequency. A full numerical simulation of the Gross-Pitaevskii equation giving the frequencies and amplitudes of the observed modes between these two limits is compared to the data and is used to understand the origin of the higher mode. Implications for trapped matter-wave interferometers are discussed.

[Multiple penetrating brain injuries caused by a nail gun: a case report]. / Heridas múltiples penetrantes intracraneales causadas por pistola de clavos: caso clínico.

Multiple and self-inflicted penetrating brain injuries (PBI) rare. PBI are rare. We report the case of multiple self-inflicted PBI in a 45 year old man caused by a nail gun. He was admitted to after shooting four nails into his head and one into his thorax. We review the literature on the topic and describe how this case was successfully managed in our hospital.

Controlling attosecond double ionization dynamics via molecular alignment.

We investigate the dynamics of double ionization in aligned nitrogen molecules. An ultrashort, weak laser pulse creates an aligned ensemble of molecules that is ionized with a subsequent, strong probe pulse. We find that the two electrons involved in nonsequential double ionization more likely exit the molecule in the same direction if it is parallel to the probe laser polarization, indicating that they are ejected within a few hundred attoseconds of each other. Double ionization is less probable and takes longer for perpendicular molecules.

Toxic effects of lemon peel constituents on Ceratitis capitata.

A series of experiments were conducted to evaluate the toxicity of lemon peel extracts incorporated into mediterranean fruit fly Ceratitis capitata diet. Extracts were obtained with different solvents: diethyl ether, ethyl acetate, and methanol. All three extracts were toxic to some extent; the diethyl ether extract was selected for further studies. Ether extracts of lemon peel were prepared weekly over a 2-month period, from fruits collected on the 1st d of the bioassay. Weekly GC-MS and UV analyses of the extracts demonstrated that the concentration of citral and coumarins decreased in the peel after harvest. We conducted a series of bioassays to evaluate the toxicity of the ether extract, and mixtures of this extract with citral, 5,7-dimethoxycoumarin. and linalool incorporated to C. capitata larvae's natural diet (lemon slices endocarp) at a concentration of 250 microg/g of diet. Significant larvicidal activity can be obtained from a fresh lemon peel extract; however, when the extract was obtained from stored lemons, toxicity decreased. Addition of small amounts of citral or 5,7-dimethoxycoumarin, and linalool to the stored lemon peel extract would bring back the toxicity to the rates of fresh lemons extracts. Finally, female adults of C. capitata fed on diets containing additional amounts of ether extract, 5,7-dimethoxycoumarin, and linalool, were exposed to different photoperiods to test for phototoxicity. The treatment was toxic and affected the oviposition capacity of females depending on photoperiod.

[The oncology patient in emergencies. Epidemiological data]. / Enfoque global del enfermo oncológico en urgencias. Datos epidemiológicos.

Oncology patients do not form a large proportion within the overall figures of an emergency service, but their clinical characteristics mean that attending to them is often complex. The elaboration of a complete clinical history, specifying the characteristics and stage of the tumoural disease, is a basic weapon for taking decisions when an emergency arises. According to the data from our centre, oncology patients account for 5% of the total of emergency cases. The most frequent type of tumour that we deal with is pulmonary, followed by breast and colon. It is often the case that these patients come to the emergency department several times in the same month and pain is the most frequent reason for consultation, although it is normal for them to mention several causes on each occasion. In a high percentage of cases the reason for the consultation is related to the disease itself, but on as many as 35% of occasions it is an intercurrent pathology. The index of admissions is high (around 50%), especially if the patient has come for a reason related to the disease. In global terms, they account for 14% of total admissions from emergencies.

New coumarins from Pterocaulon polystachyum.

Aerial parts of Pterocaulon polystachyum from Chaco province, Argentina, afforded the known coumarins ayapin, isoscopoletin, prenyletin, prenyletin methyl ether, virgatenol, obtusinin, 5-methoxy-6,7-methylenedioxycoumarin, 5-(3,3-dimethylallyloxy)-6,7-methylenedioxycoumarin, 5-(2',3'-dihydroxy-3-methylbutanoxy)-6,7-methylenedioxycoumarin, haplopinol methyl ether, 6-(1,1-dimethyl-2-propenyl)-7-hydroxycoumarin and demethylnieshoutin; the last two are new as natural products while the five new coumarins from the collection were isovirgatenol, 3'-deoxyobtusinin, 6-methoxy-7-(2'-hydroxyethoxy)-coumarin, 5-(2'-hydroxyethoxy)-6,7-methylenedioxycoumarin and a substance tentatively identified as 5-hydroxy-6,7-methylenedioxy-8-(3,3-dimethylallyl)-coumarin.

Melampolides from Enydra anagallis.

The investigation of an Argentine collection of Enydra anagallis afforded sesquiterpene lactones of the melampolide type two of which were previously known. Their structures were elucidated by spectroscopic methods.

Sesquiterpene lactones and other constituents of Disynaphia multicrenulata from Argentina.

Flowers and leaves of Disynaphia multicrenulata from Argentina afforded a large number of known germacradienolides and heliangolides, a new germacradienolide, a known melampolide, a new parthenolide derivative, one known and seven new cronquistiolides, a new 4Z-melampolide, three known and five new eudesmanolides, a new elemadienolide, a known grazielolide, an isoguaiagrazielolide, two diepoxygermacran-8,12-olides, three common kauranoic acids, pinoresinol, jaceosidin and the sesquiterpene oplopanone. Structures were elucidated by high-field 1H NMR spectrometry. The relationship to the known chemistry of other members of the Disynaphiinae is discussed.

Allelopathic agents from Cyrtocymura cincta.

The sesquiterpenoid fractions from the chloroform extracts of roots and aerial parts of the weed Cyrtocymura cincta (Griseb.) H. Robinson (Compositae) were tested to observe the effects on seed germination and growth of three dicot and four monocot species. Promotion and inhibition effects were observed according to the examined compound, specific seed or cultivar, and concentration.

Germacranolides and a new type of guaianolide from Acanthospermum hispidum.

The aerial parts of an Argentinian collection of Acanthospermum hispidum afforded 26 sesquiterpene lactones, including the two guaianolides (1 and 2) having a novel oxygen bridge between C-4 and C-14, three new cis,cis-germacranolides (4, 7, and 8), and two new melampolides (25 and 26). Guaianolides 1 and 2 seem to derive biosynthetically from the germacranolide 27 having the (1)D(14, 15)D(5) conformation. The structures were elucidated using extensive spectroscopic analysis.

HHV8 and female Kaposi's sarcoma.

Kaposi's sarcoma (KS) is an enigmatic tumour of uncertain histogenesis. Epidemiological data have long suggested that KS may be caused by an infectious agent, possibly sexually transmitted. Following the documentation of human herpesvirus 8 (HHV8) and its strong association with all forms of KS, it now appears that the putative agent has at last been identified. As KS is rare in females, a unique group was screened for the presence of HHV8 using both conventional solution-phase polymerase chain reaction (PCR) and the newly described technique of TaqMan PCR. The presence of HHV8 was demonstrated in 10/12 of these female patients. This further supports the direct role of HHV8, in conjunction with cytokines and other factors, in the pathogenesis of KS.