Imaging palpable tumors in pediatrics: Part 2.

Palpable tumors in children are a common reason for consulting a radiologist. The origin of these lesions varies widely, and although they are common, classic radiology books do not cover some of them. This series of two articles aims to review the clinical and radiological characteristics of a selection of palpable tumors in children that radiologists need to be familiar with.

Radiología de las tumoraciones palpables en el paciente pediátrico. Parte 2 / Imaging palpable tumors in pediatrics: Part 2

Las tumoraciones palpables en los niños son un motivo de consulta muy habitual para el radiólogo. El origen de las lesiones es muy variado, y algunas de ellas no reciben atención en los libros clásicos de Radiología, pese a encontrarse frecuentemente.El objetivo de esta serie de 2 artículos es revisar las características clínico-radiológicas de una selección de estas entidades que consideramos importante conocer. (AU)

Palpable tumors in children are a common reason for consulting a radiologist. The origin of these lesions varies widely, and although they are common, classic radiology books do not cover some of them.This series of two articles aims to review the clinical and radiological characteristics of a selection of palpable tumors in children that radiologists need to be familiar with. (AU)

Imaging palpable tumors in pediatrics.

Palpable tumors in children are a common reason for consulting a radiologist. The differential diagnosis is extensive and considerably different from that used in adults. Some of the etiologies of palpable tumors are little known outside of pediatrics. The most commonly used imaging test is ultrasonography, because in addition to being harmless and cost-effective, it is conclusive in most cases. Most palpable lesions in children are benign; it is estimated that only 1% are malignant. Knowing these lesions enables the correct diagnosis without the need to resort to unnecessary, sometimes invasive tests, thus avoiding delays in treatment when more severe disease is present. This article aims to review the clinical and radiological characteristics of the palpable lesions that are most common in pediatric patients, explaining the key features that enable accurate diagnosis.

Radiología en las tumoraciones palpables del paciente pediátrico Parte 1 / Imaging palpable tumors in pediatrics

La presencia de una tumoración palpable en un niño es un motivo de consulta frecuente en Radiología. El diagnóstico diferencial es extenso y considerablemente diferente al del adulto. Algunas de las etiologías son poco conocidas fuera del ámbito pediátrico. La prueba de imagen más utilizada es la ecografía, porque además de inocua y coste-efectiva, es concluyente en la mayoría de los casos. La mayor parte de las lesiones son de naturaleza benigna. Se estima que solo el 1% terminan en un diagnóstico de neoplasia maligna. Conocerlas permite hacer un diagnóstico correcto, sin tener que recurrir a pruebas innecesarias y a veces invasivas, así como evitar retrasos en el proceso asistencial cuando nos encontremos ante una enfermedad de mayor gravedad. El objetivo de este artículo es repasar las características clínico-radiológicas de las tumoraciones palpables más frecuentes en el paciente pediátrico, explicando los datos clave que permitan hacer un diagnóstico preciso.(AU)

Palpable tumors in children are a common reason for consulting a radiologist. The differential diagnosis is extensive and considerably different from that used in adults. Some of the etiologies of palpable tumors are little known outside of pediatrics. The most commonly used imaging test is ultrasonography, because in addition to being harmless and cost-effective, it is conclusive in most cases. Most palpable lesions in children are benign; it is estimated that only 1% are malignant. Knowing these lesions enables the correct diagnosis without the need to resort to unnecessary, sometimes invasive tests, thus avoiding delays in treatment when more severe disease is present. This article aims to review the clinical and radiological characteristics of the palpable lesions that are most common in pediatric patients, explaining the key features that enable accurate diagnosis.(AU)

An overview on production, consumer perspectives and quality assurance schemes of beef in Mexico.

Mexico has a large beef production industry that has grown significantly in the last decade. The export market has increased, however, domestic beef consumption has declined. A knowledge of the factors affecting consumer perceptions and acceptance of beef might highlight critical points that could improve the whole industry, and lead to an increase of export and domestic consumption. The present paper is aimed to provide an overview on the dynamics of Mexican beef production systems, the current perceptions of the Mexican consumer for beef, and the current available beef quality assurance schemes, based on published and official information.

Caffeoyl and coumaroyl derivatives from Acacia cochliacantha exhibit ovicidal activity against Haemonchus contortus.

ETHNOPHARMACOLOGY RELEVANCE: Acacia cochliacantha is a small tree whose foliage is traditionally used in Mexico for treatment of kidney pain, gastrointestinal illnesses and to kill intestinal parasites. In recent decades, the study of vegetal extracts has offered other possible alternatives for the control of Haemonchus contortus. Considering that this nematode affects dramatically the health and productivity of small ruminants, the aim of this study was to identify the anthelmintic compounds from A. cochliacantha hydro-alcoholic extract (HA-E) through an ovicidal test. MATERIAL AND METHODS: In vitro egg hatch assay was conducted to determinate the anthelmintic effects of a HA-E (60g). Liquid-liquid ethyl acetate/water extraction gave two fractions (EtOAc-F, 1.92g; Aq-F; 58.1g). The less polar compounds from ethyl acetate fraction were extracted by addition of dichloromethane offering a precipitate phase (Mt-F, 1.25g) and a soluble mixture (DCMt-F 1.15g). All fractions were evaluated for ovicidal activity obtaining the egg hatching inhibition (EHI, 0.07-25mg/mL). Ivermectin (0.5mg/mL) was used as a reference drug (positive control), and distilled water, 2.5% DMSO and 2% methanol were used as negative controls. The isolated compounds from the most active fractions were subjected to spectroscopic (1H NMR) Spectrometric (MS) and UV HPLC analysis in order to identify the bioactive compounds. RESULTS: The less polar treatments (AcOEt-F, DCMt-F, DCMt-P) showed the highest ovicidal activities (98-100% EHI; at 0.62-1.56mg/mL) and the major compounds found in these fractions were identified as caffeoyl and coumaroyl derivatives, including caffeic acid (1), p-coumaric acid (2), ferulic acid (3), methyl caffeate (4), methyl-p-coumarate (5), methyl ferulate (6) and quercetin. In case of the less active fractions (Aq-F, Mt-F) were constituted principally by glycosylated flavonoids. CONCLUSION: These results show that caffeoyl and coumaroyl derivatives from Acacia cochliacantha leaves had promising anthelmintic activity against Haemonchus contortus. This leguminous may offer an alternative source for the control of gastrointestinal nematodes of small ruminants.

One- and Two-Dimensional Nuclear Magnetic Resonance Spectroscopy with a Diamond Quantum Sensor.

We report on Fourier spectroscopy experiments performed with near-surface nitrogen-vacancy centers in a diamond chip. By detecting the free precession of nuclear spins rather than applying a multipulse quantum sensing protocol, we are able to unambiguously identify the NMR species devoid of harmonics. We further show that, by engineering different Hamiltonians during free precession, the hyperfine coupling parameters as well as the nuclear Larmor frequency can be selectively measured with up to five digits of precision. The protocols can be combined to demonstrate two-dimensional Fourier spectroscopy. Presented techniques will be useful for mapping nuclear coordinates in molecules deposited on diamond sensor chips, en route to imaging their atomic structure.

In vitro gas production of foliage from three browse tree species treated with different dose levels of exogenous fibrolytic enzymes.

The aim of this study was to evaluate the effect of different dose levels of exogenous fibrolytic enzymes (EFE) on in vitro ruminal fermentation kinetics and energy utilization of foliages from three browse trees (Pithecellobium dulce, Heliocarpus velutinus and Guazuma ulmifolia). Mixture of EFE product was added to the leaves of the three browse tree species at three dose levels: 0 (control), 3.5 and 7.0 mg/g of DM. Chemical composition of the foliages, including plant secondary metabolites such as total phenolics (TP), saponins (SAP) and aqueous fraction (AF), was determined. In addition, in vitro assaying of ruminal gas production kinetics was determined for the three browse three foliages treated with EFE. P. dulce had the highest crude protein content (p < 0.05), whereas G. ulmifolia had the highest content of neutral detergent fibre and SAP (p < 0.05) and H. velutinus had the lowest content of TP (p < 0.05). The interaction between tree species and dose level of EFE was significant (p < 0.05) for gas production (GP) at 24 h of incubation, parameters b and c of the accumulated GP curve, short-chain fatty acids (SCFA) and metabolizable energy (ME). The lowest (p < 0.01) extent of accumulated GP as well as the b and c values occurred in G. ulmifolia at 0 mg EFE/g DM. P. dulce had the highest (p < 0.05) values for ME and SCFA at the highest dose of EFE. Tree species and dose level had significant (p < 0.05) effects on all parameters describing in vitro ruminal fermentation kinetics and energy utilization. Addition of EFE improved the fermentation kinetics of the browse species considered in this study.

[Serious complications after pulmonary radiofrequency ablation: report of 2 cases]. / Dos casos de complicaciones graves tras radiofrecuencia pulmonar.

Radiofrequency ablation can be used to treat primary or metastatic pulmonary tumors when surgery is not indicated or involves high risk. Although this technique is less invasive than surgical resection, it is not free of risk for complications and adverse events, especially when it is used in patients with serious respiratory disease in whom comorbidity is common. We report 2 cases of serious complications. One was an intractable air leak that led to death. The other was a large hemothorax that was brought under control in the radiology procedure room. We review the literature on this technique as well as recommendations that contribute to making it as safe as possible.

Droplet evolution in expanding flow of warm dense matter.

We propose a simple, self-consistent kinetic model for the evolution of a mixture of droplets and vapor expanding adiabatically in vacuum after rapid, almost isochoric heating. We study the evolution of the two-phase fluid at intermediate times between the molecular and the hydrodynamic scales, focusing on out-of-equilibrium and surface effects. We use the van der Waals equation of state as a test bed to implement our model and study the phenomenology of the upcoming second neutralized drift compression experiment (NDCX-II) at Lawrence Berkeley National Laboratory (LBNL) that uses ion beams for target heating. We find an approximate expression for the temperature difference between the droplets and the expanding gas and we check it with numerical calculations. The formula provides a useful criterion to distinguish the thermalized and nonthermalized regimes of expansion. In the thermalized case, the liquid fraction grows in a proportion that we estimate analytically, whereas, in case of too rapid expansion, a strict limit for the evaporation of droplets is derived. The range of experimental situations is discussed.

Aneurisma micótico mesentérico: rara complicación de una endocarditis bacteriana / Mesenteric mycotic aneurysm: A rare complication of a bacterial endocarditis

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Probing three-body correlations in a quantum gas using the measurement of the third moment of density fluctuations.

We perform measurements of the third moment of atom number fluctuations in small slices of a very elongated weakly interacting degenerate Bose gas. We find a positive skewness of the atom number distribution in the ideal gas regime and a reduced skewness compatible with zero in the quasicondensate regime. For our parameters, the third moment is a thermodynamic quantity whose measurement constitutes a sensitive test of the equation of state, and our results are in agreement with a modified Yang-Yang thermodynamic prediction. Moreover, we show that the measured skewness reveals the presence of true three-body correlations in the system.

[Orotracheal tube ignited by an electrocautery device during tracheostomy]. / Ignición del tubo orotraqueal inducida por electrocauterio durante una traqueostomía.

Endotracheal tube fire during surgery is a rare complication associated with carbon dioxide laser surgery and, less often, with electrocautery. We report a case in which tracheostomy was performed because of recurrence of a laryngeal tumor. During the procedure the endotracheal tube ignited when the lumen was opened with the electrocautery device.

[Rational combination therapy in epilepsy. III. Possible associations between antiepileptic drugs]. / Politerapia racional en epilepsia. III. Posibles asociaciones de antiepilépticos.

INTRODUCTION: As the foundation underlying rational combination therapy it is necessary to consider the mechanism of action of each antiepileptic drug, its spectrum, the safety and pharmacodynamic and pharmacokinetic interactions, and to select the association of antiepileptic drugs in accordance with these factors. DEVELOPMENT: This paper consists of three parts. In this third part we consider possible associations between antiepileptic drugs; we suggest associations that may be beneficial, others that must be kept under surveillance because their advantages can be offset by their drawbacks, and others that should be avoided because their disadvantages outweigh their possible advantages. CONCLUSIONS: Until more is known about the aetiopathogenesis of epilepsy and we have markers of the cause of epilepsy in a particular patient it will not be possible to associate antiepileptic drugs according to their mechanisms of action. The absence of clinical trials only allows us to make suggestions about possible beneficial or harmful associations depending on the pharmacodynamic and pharmacokinetic characteristics of antiepileptic drugs, which can thus enhance their effectiveness and safety.

[Rational combination therapy in epilepsy. II. Clinical and pharmacological aspects]. / Politerapia racional en epilepsia. II. Aspectos clínicos y farmacológicos.

INTRODUCTION: From an analysis of the studies published to date, the criteria used to select the antiepileptic drugs that can be associated for the treatment of a particular situation or patient need to be optimised because combination therapy offers a low level of evidence. It is also acknowledged that it is advisable to begin treatment with monotherapy (although 30% of patients do not respond and in such cases combination therapy is usually employed), but the possibility of starting with bitherapy in epilepsies that are usually resistant to treatment has also been suggested. DEVELOPMENT: This paper consists of three parts. This second part reviews the foundations underlying the rational association of antiepileptic drugs. CONCLUSIONS: For the association of antiepileptic drugs to result in increased effectiveness without raising the level of toxicity, the theoretical bases of rational combination therapy take into account the mechanism of action, the spectrum, the safety, and the pharmacodynamic and pharmacokinetic interactions of each antiepileptic drug; the number of times the drug is taken is another factor to be taken into consideration. Although it is still early to associate two antiepileptic drugs on the basis of their mechanism of action, these theoretical foundations suggest a sodium channel inhibitor should be associated with a GABAergic agent or an antiepileptic with multiple mechanisms and that we should avoid the association between antiepileptic drugs with additional (sedative and neurological) toxicity or that are likely to interact. Evaluation of the effectiveness, safety, interactions and number of doses suggests the following order, from more to less suitable for combination therapy: levetiracetam/pregabalin > gabapentin > lamotrigine > oxcarbazepine/topiramate/zonisamide > tiagabine > valproic acid > carbamazepine > phenytoin > phenobarbital/primidone > benzodiazepines.

[Rational combination therapy in epilepsy. I. Concepts and foundations]. / Politerapia racional en epilepsia. I. Concepto y fundamentos.

INTRODUCTION: It is an accepted fact that it is wise to start antiepileptic treatment with monotherapy, but 30% of patients do not respond to it or to several monotherapies; in that moment an association of two or more antiepileptic drugs is commonly utilised (the appearance of ten second-generation antiepileptic drugs on the market has not changed this scenario to any significant extent). Yet, on the other hand, the use of bitherapy in epilepsies that are usually resistant to treatment has been suggested as a interesting way to begin treatment. DEVELOPMENT: This article consists of three parts. In this first part we review the concept of rational combination therapy, the concept of how and when it should be used and the studies about associations of antiepileptic drugs conducted in animals and in humans. CONCLUSIONS: Although combination therapy is frequent as treatment for epilepsy, it is not always so obvious that it offers more benefits in terms of greater effectiveness with a lower, or at least equal, degree of toxicity. Few methodologically correct clinical trials have been conducted and recent reviews continue to consider that no controlled clinical trials have been carried out that confirm the benefits of combination therapy. This does not mean, however, that rational combination therapy is totally void of any kind of usefulness, but rather it stresses the fact that it offers a low level of evidence.

[Mechanism of action of antiepileptic drugs and new antiepileptic drugs]. / Mecanismo de acción de los antiepilépticos y nuevos antiepilépticos.

INTRODUCTION: Although 10 second generation new antiepileptic drugs are currently available on the market, 30% of patients are resistant to pharmacological treatment. In addition, today's antiepileptic drugs avert or suppress seizures but do not prevent the appearance of epilepsy or its progression. DEVELOPMENT: The foundations of the aetiopathogenesis of epilepsy and the main targets of antiepileptic drugs are described. Describing the important role of gamma-aminobutyric and glutamic acid in the genesis and proliferation of the seizures has allowed for the development of new antiepileptic drugs that increase the inhibitory tone of GABA or inhibit the excitatory tone of glutamate. The discovery that some epilepsies may be due to channelopathies is now making it possible to conduct research into drugs that inhibit calcium channels, activate potassium channels or inhibit abnormal AMPA/KA receptor channels. Recent reports describing a specific attachment of some antiepileptic drugs to the a2d subunits of the calcium channel and to the synaptic vesicles proteins SV2A open up new perspectives. Moreover, research is also being carried out on new drugs that are capable of preventing epileptogenesis, stemming the progression of epilepsy or overcoming the resistance to pharmacological treatment displayed by some epilepsies. CONCLUSIONS: The identification of new pharmacological targets in the aetiopathogenesis of epilepsies has made it possible to develop second generation antiepileptic drugs and it is allowing for the development of third generation antiepileptic drugs.

Mecanismo de accion de los antiepilepticos y nuevos antiepilepticos / Mechanism of action of antiepileptic drugs and new antiepileptic drugs

Introducción. A pesar de la comercialización de 10 antiepilépticosnuevos de segunda generación, hay un 30% de pacientesresistentes al tratamiento farmacológico. Además, los antiepilépticosactuales previenen o suprimen las crisis pero no evitan laaparición de epilepsia ni su progresión. Desarrollo. Se describenlos fundamentos de la etiopatogenia de la epilepsia y las principalesdianas de los antiepilépticos. La descripción del importante papeldel ácido gamma-aminobutírico y el glutámico en la génesis yla propagación de las crisis han permitido desarrollar nuevos antiepilépticosque aumenten el tono inhibidor gabérgico o inhiban eltono excitador glutamérgico. El descubrimiento de que algunasepilepsias pueden deberse a canalopatías está permitiendo investigarfármacos que inhiban canales de calcio, activen canales depotasio o inhiban canales anómalos de receptores AMPA/KA. Recientementese ha descrito una fijación específica de algunos antiepilépticosa las subunidades a2d del canal de calcio y a las proteínasde las vesículas sinápticas SV2A que abren nuevas perspectivas.Por otra parte, se investigan fármacos nuevos que puedanprevenir la epileptogénesis, evitar la progresión de la epilepsia ovencer la resistencia al tratamiento farmacológico de algunas epilepsias.Conclusión. La identificación de nuevas dianas farmacológicasen la etiopatogenia de las epilepsias ha permitido el desarrollode los antiepilépticos de segunda generación y está permitiendodesarrollar nuevos antiepilépticos de tercera generación

Introduction. Although 10 second generation new antiepileptic drugs are currently available on the market, 30% ofpatients are resistant to pharmacological treatment. In addition, today’s antiepileptic drugs avert or suppress seizures but do notprevent the appearance of epilepsy or its progression. Development. The foundations of the aetiopathogenesis of epilepsy and themain targets of antiepileptic drugs are described. Describing the important role of gamma-aminobutyric and glutamic acid in thegenesis and proliferation of the seizures has allowed for the development of new antiepileptic drugs that increase the inhibitorytone of GABA or inhibit the excitatory tone of glutamate. The discovery that some epilepsies may be due to channelopathies isnow making it possible to conduct research into drugs that inhibit calcium channels, activate potassium channels or inhibitabnormal AMPA/KA receptor channels. Recent reports describing a specific attachment of some antiepileptic drugs to the a2d subunits of the calcium channel and to the synaptic vesicles proteins SV2A open up new perspectives. Moreover, research is alsobeing carried out on new drugs that are capable of preventing epileptogenesis, stemming the progression of epilepsy orovercoming the resistance to pharmacological treatment displayed by some epilepsies. Conclusions. The identification of newpharmacological targets in the aetiopathogenesis of epilepsies has made it possible to develop second generation antiepilepticdrugs and it is allowing for the development of third generation antiepileptic drugs