Effectiveness of nanoemulsions of clove and lemongrass essential oils and their major components against Escherichia coli and Botrytis cinerea.

Nanoemulsions exhibit a number of advantages to carry and deliver lipophilic compounds such as essential oils (EOs) due to their good stability and high surface area per volume unit. The purpose of this work was to assess the long-term stability of nanoemulsions of clove and lemongrass (LG) EOs and their principal components eugenol and citral (CI), respectively, at 3 different concentrations (2, 5 or 10 times their respective minimum inhibitory concentrations) and at two storage temperatures (1 °C and 21 °C). The initial droplet size of LG and CI-loaded nanoemulsions was below 100 nm and most of them kept droplet sizes in the nano-range until the end of storage at both temperatures. The ζ-potential was lower than - 40 mV, but it increased through storage, indicating a weaker alginate adsorption at the oil surface at both temperatures. The antimicrobial activity increased with the EOs concentration and was negatively affected by the highest storage temperature. Nanoemulsions containing CI and LG were able to significantly decrease Escherichia coli counts during storage, particularly at 1 °C. Nanoemulsions containing 1.0 and 2.0% w/w CI and 2.5% w/w LG were the most efficient in reducing Botrytis cinerea growth through storage, mainly at 1 °C. The nanoemulsions containing 1.0 and 2.0% w/w CI, as well as, 1.25 and 2.5% w/w LG better maintained their stability and antimicrobial effect along 6-months storage mainly when at 1 °C, making those nanoemulsions suitable as edible coatings for food preservation. Future studies should be oriented to evaluate the impact of these nanoemulsions on the organoleptic properties of coated foods and their potential toxicity.

Fluorine sorption by soils developed from various parent materials in Galicia (NW Spain).

Fluorine is a phytotoxic element that can reach the soil from various industrial activities. Fluorine sorption by soil is crucial to protect water and food chain from fluorine pollution. In Galicia (NW Spain), various activities emit fluorine into the atmosphere, mainly ceramic industries and an aluminium smelter. This study, aiming to investigate fluorine sorption by Galician soils, was conducted on natural soil horizons representative of the area. Most soils were acid and rich in organic matter and showed strong fluorine sorption. The lowest sorptions were exhibited by a near-neutral serpentinite-derived soil (1001 mg kg(-1)) and the B horizons of soils developed from quartz schist (989 mg kg(-1)), and the highest by the A horizons of amphibolite-derived soils (1783 mg kg(-1)). In soils developed from quartz schist, biotitic schist and amphibolite, A horizons sorbed more fluoride than the corresponding B horizons (average 1621 and 1324 mg kg(-1), respectively), while the opposite is true in granite-derived soils (average 1644 and 1324 mg kg(-1), respectively). In the A horizons, the F sorption significantly correlated to soil pH (r=-0.79), pH in NaF (r=0.83) and oxalate Al (r=0.81). In the B horizons, sorption correlated to soil pH (r=-0.78), oxalate Fe (r=0.71) and organic C (r=0.66). F sorption can be described by both the Langmuir and Freundlich equations. The concentration of free fluoride in the equilibrium solutions increased above pH 6.

Investigation of the afterglow time regime in pulsed radiofrequency glow discharge time-of-flight mass spectrometry.

The pulsed power operation mode of a radiofrequency (rf) glow discharge time-of-flight mass spectrometer was investigated, for several ions, in terms of intensity profiles along each pulse period. Particular attention was paid to the plateau and transient afterglow regions. An rf pulse period of 4 ms and a duty cycle of 50% was selected to evaluate the influence of discharge parameters in the afterglow delay and shape of Ar(+), Ar(2)(+) and several analytes (Br, Cl, Cu) contained in polymeric layers. Pulse shapes of Ar(+) and Ar(2)(+) ions vary with pressure and power. At low pressures the highest intensity is observed in the plateau while at higher pressures (>600 Pa) the afterpeak is the dominant region. Although the influence of the applied power is less noticeable, a widening of the afterglow time regime occurs for Ar(+) when increasing the power. Maximum intensity of the argon signal is measured in the afterglow at 30 W, while the area of such afterpeak increases with power. The maximum intensity of Ar(2)(+) is obtained at the highest power employed (60 W) and the ratio maximum intensity/afterglow area remains approximately constant with power. Analytes with ionization potentials below (Cu) or just above (Br) the argon metastable energy show maxima intensities after argon ions decay, indicating they could be ionized by collisions with metastable Ar atoms. Chlorine signals are observed in the afterglow despite their ionization potential is well above the energy of argon metastable levels. Moreover, they follow a similar pattern to that observed for Ar(2)(+) , indicating that charge-transfer process with Ar(2)(+) could play a significant role.

Stevens-Jonhson syndrome after acetaminophen ingestion, confirmed by challenge test in an eleven-year-old patient

No disponible

Analysis of small bubbles in glass by glow discharge--time-of-flight mass spectrometry.

The chemical reactions occurring during the glass manufacturing processes can give rise to small bubbles, damaging the required glass properties. To avoid eventual bubbles formation, the chemical composition of the bubbles should be known to trace back the gas sources and take appropriate corrective actions. Mass spectrometry is a most adequate detection technique for such purpose due to its ability to provide the required information in a short time. Analysis of these small bubbles in glass requires a system incorporating a very small volume (for a fast evacuation of the entire line and low dilution of the analytes) and a fast mass analyser allowing the quasi-simultaneous detection of the whole spectral interval of interest, such as a time-of-flight mass spectrometer (TOFMS). In this work, the analytical potential of a radiofrequency glow discharge (rf-GD) coupled to a TOFMS was evaluated for the first time for the analysis of bubbles in glasses. The operating conditions of the rf-GD (pressure and applied power) were optimized by introducing into the system known volumes of air. Detection limits in the order of nL were obtained for molecular nitrogen, oxygen and carbon dioxide. Finally, a stainless steel bellows valve was modified to serve as glass breaker for the sampling process. This valve was connected on-line to the mass spectrometer inlet line and proved to be most appropriate for the analysis of the gaseous content of bubbles (with diameters below 0.5mm) entrapped in industrial glasses.

¿Hasta dónde con los estudios genéticos en neurología pediátrica? / How valuable are genetic studies in paediatric neurology?

Introducción y desarrollo. La neurología pediátrica no ha permanecido ajena a la aplicación de los grandes avances genéticos al diagnóstico clínico y prenatal de una amplia variedad de enfermedades. El descubrimiento de nuevos genes relacionados con un número creciente de patologías con implicaciones neurológicas ofrece nuevos planteamientos diagnósticos y provee una información de gran utilidad en el proceso de detección de portadores e identificación de individuos presintomáticos. La disponibilidad de técnicas genéticas más selectivas y de mayor resolución, así como la posibilidad de secuenciación y búsqueda de mutaciones concretas para algunos genes, es cada vez mayor en los laboratorios de genética, y su aplicación a la clínica ha permitido que para algunos procesos suponga la aproximación diagnóstica inicial. Una orientación clínicaprecisa, y el conocimiento de sus aplicaciones y limitaciones es fundamental y, cada vez más, exige una estrecha relación entre clínicos y genetistas para el diseño individualizado de un protocolo diagnóstico que ofrezca un equilibrio racional entre disponibilidad técnica, coste, tiempo y relevancia de los hallazgos. Conclusiones. Se plantean algunos aspectos actuales y reflexiones sobre avances en patologías neuropediátricas concretas, dentro del grupo de los trastornos neuromusculares, retraso mental, trastornos del espectro autista y epilepsia

Introduction and development. Paediatric neurology is fully aware of the fact that important advances in genetics are being applied to the clinical and prenatal diagnoses of a wide range of diseases. The discovery of new genes related to a growing number of pathologies with neurological implications opens up new diagnostic approaches and provides information that is veryuseful in the process of detecting carriers and identifying pre-symptomatic individuals. More selective genetic techniques with higher resolutions are increasingly more commonly available in genetic laboratories, as is the possibility of sequencing andsearching for specific mutations in certain genes; for some processes their application to clinical practice has made them the initial diagnostic approach. A precise clinical orientation and knowledge of their applications and limitations is essential, and requires an increasingly close relationship between clinicians and geneticists in order to design a tailored diagnostic protocol that offers a rational balance between technical availability, cost, time and relevance of the findings. Conclusions. We discuss some of the current aspects and considerations about advances in specific neuropaediatric pathologies, within the group of neuromuscular disorders, mental retardation, autism spectrum disorders and epilepsy

[Can we increase phosphate removal with conventional hemodialysis?]. / Se puede aumentar la eliminación de fósforo con la hemodiálisis convencional?

BACKGROUND: The aim of the present study was to investigate the effect of different dialysate buffer and glucose concentrations, membrane surface (S) bigger than 2 m2 and increased dialysate flow (Qd) in phosphate (P) removal. METHODS: A. First phase (5 patients): the following variations in dialysate composition were introduced. A: glucose 1.60 g/L, bicarbonate: 39 mEq/L, acetate 4 mEq/L, B: glucose 1.5 g/L bicarbonate 17 mEq/L, acetate 10 mEq/L; C: glucose 0, bicarbonate: 39 mEq/L, acetate 4 mEq/L; and D: glucose 0, bicarbonate 17 mEq/L, acetate 10 mEq/L. B. Second phase (14 patients): variations in S and Qd were: 1. Qd: 500 mL/min + Hemophan 2 m2, 2. Qd: 500 mL/min + Hemophan 2.6 m2, 3. Qd: 750 mL/min + Hemophan 2 m2, 4. Qd: 750 mL/min + Hemophan 2.6 m2. RESULTS: Comparing HDs performed with low bicarbonate (B and D) respect to current buffer formulations (A and C), total P removal was 997.3 (+/- 237.3) vs 882 (+/- 216.1) mg (p NS). No differences were found by grouping the sessions according to glucose concentration. There were no significant differences in total phosphate removal between the two different S or Qd. The most important predictive factor of total P removal was the initial P and 2 hours serum P concentration, and PTH concentration. CONCLUSIONS: i) Removal of P is better predicted by pre-dialysis P serum concentration; ii) P removal was not affected by the changes in bicarbonate and glucose concentration in the dialysate; iii) the increase of the dialyzer area between 2 and 2.6 m2 augments Kt/V, but without influencing P elimination; iv) a higher Qd does not determine significant differences in P removal and v) higher PTH is associated with a higher P elimination.

Ultrafiltración aislada, ¿unipunción o bipunción? / Isolated infiltration, single or double punction?

La excesiva ganancia de peso interdiálisis es un importante problema en la población en hemodiálisis que requiere, en ocasiones, la realización de sesiones extra de Ultrafiltración (UF) aislada, lo que supone un mayor número de punciones del acceso vascular. Por este motivo, nos planteamos utilizar técnicas de unipunción para realizar estas sesiones y así mejorar la supervivencia del acceso vascular y con ello la calidad de vida de los pacientes. Para ello estudiamos 38 sesiones de UF aislada en 10 pacientes; 25 en bipunción y 13 en unipunción. El análisis de los parámetros clínicos y bioquímicos, no reveló diferencias significativas entre ambos grupos, por lo que concluimos que las sesiones de UF aislada son igualmente efectivas con ambas técnicas. Además el número de punciones del acceso vascular fue menor con la técnica de unipunción lo que supone un mejor cuidado del acceso vascular y un aumento de fa calidad de vida de estos pacientes (AU)

[Why do ambulatory hemodialysis patients go to hospital emergency services? / Por qué acuden los pacientes de hemodiálisis extrahospitalaria a los servicios de urgencia hospitalarios?

UNLABELLED: An important number of Hospital admissions (HA) occurs through Hospital Emergency Departments (HED). This is a indicator of quality and have to be lower than 50%. However there are almost no data available on the causes of emergency consultation by outpatient hemodialysis patients (HD). For this reason, we prospectively examined a population of 83 outpatient HD patients dialyzed in a peripheral unit under the surveillance of a University Hospital. OBJECTIVES: 1) To know the diagnosis of HED and days of hospitalization for which HD patients came to the HED in 1998. 2) To know the possible risk factors associated with the patients with frequent assistance in HED. 3) To compare the number and causes of emergency consultation in 1998 with a group of patients treated in the same Unit in 1991 (n = 39). RESULTS: The percentage of patients who used the HED in 1998 was 66.3% (55/83). The total number of emergency episodes in 1998 was 118 (mean of 55 patients 2.27 +/- 1.51). Fifty one percent of the emergency episodes were due to patients initiative. The 4 more frequent diagnoses of HED in 1998 were infectious, 19.5% (23/118); traumatologic emergencies, 15.3% (18/118); digestive disease 15.3% (18/118); relationed problem vascular access, 11.9% (14/118). Thirty percent (36/118) of the emergency consultations needed HA leading to a mean hospitalitation of 10.2 +/- 9.3 days. The infectious disease were the highest percentage of HA (36.1%) and the longest days of hospitalitation (12.7 +/- 11.2 days). The risk factors for repeated emergency consultation (more than 3 times) were: age (68.9 vs 61.4), lower hematocrit (31.6 vs 34.4%), lower hemoglobin (10.2 vs 11), high EPO dose (166.3 vs 109.7 unit/kg/week) and lower Kt/V (0.99 vs 1.11). If we compare these results with 1991 the percentage that used the HED was similar 66.2% (pNS); the number of emergency episodes was higher (mean 2.99 +/- 1.96) than 1998 (p < 0.006) and there are a significant differences in the diagnoses of HED between 1998 and 1991: acute pulmonary edema 1.7 vs 11.2% (p < 0.003); hiperkalemia 0.8 vs 7.9% (p < 0.009); gastrointestinal disease 15.3% vs 4.5% (p < 0.008) and infectious 19.5% vs 7.9% (p < 0.01). In conclusion our study provides data previously not available on the epidemiology of Emergency Consultation by outpatient HD patients treated in the same peripheral unit. The data obtained albeit limited because of the number provide information of potential protocol usefulness for the possible reduction in the frequency of Hospital Emergency Consultations by outpatient HD patients.

Influence of post haemodialysis sampling on Kt/V result.

The recommended Kt/V is 1.2. Unfortunately there is no written policy for nurses on the procedure for taking blood urea nitrogen samples post haemodialysis. The aim of this study was to establish the Kt/V variability of haemodialysis patients depending on the method of collection of post-haemodialysis blood urea nitrogen. Twenty-two patients were analysed. A Kt/V was performed every 15 days during a period of 2 months. It was taken five times on each patient: 30 minutes before the end of a haemodialysis session (Kt/V30), at the end of haemodialysis (Kt/V1), after slowing flows (50 ml/min) for 2 minutes (Kt/V2) and after the blood circuit had been returned to the patient at 5 and 15 minutes respectively. (Kt/V5, Kt/V15). The Kt/V results were: Kt/V1 1.23 +/- 0.2 Vs Kt/V2 1.14 +/- 0.19 (p < 0.003); Kt/V5- 1.05 +/- 0.19 (p < 0.002 Vs Kt/V2); Kt/V15 1 +/- 0.16 (p < 0.05 Vs Kt/V5); Kt/V30 1.12 +/- 0.21 (pNS Vs Kt/V2). In conclusion, there was a large variability in the Kt/V depending on the method of collection of the blood urea nitrogen sample post-haemodialysis.

¿Por qué acuden los pacientes de hemodiálisis extrahospitalaria a los servicios de urgencia hospitalarios? / Why hemodialysis outpatients come to hospital emergency departments?

Un número importante de ingresos hospitalarios (IH) se produce a través de los servicios de urgencia hospitalarios (SUH), indicador de calidad, que se conoce como presión de urgencias, fijándose habitualmente su excelencia en ser menor del 50 por ciento. Sin embargo, apenas se dispone de estudios que analicen la utilización de los SUH por los pacientes en hemodiálisis (HD). Por este motivo hemos examinado prospectivamente durante 1998 una población de 83 pacientes dializados en una unidad satélite vinculada a un Hospital Universitario con los siguientes objetivos: 1) Conocer la vía, diagnóstico de urgencia y día de hospitalización por la que los pacientes acuden a los SUH. 2) Conocer los posibles factores de riesgo asociados a los pacientes que consultan con frecuencia a los SUH. 3) Comparar los episodios y los diagnósticos de urgencia de 1998 con un grupo histórico de pacientes de la misma unidad en 1991 (n = 39).Resultados: El porcentaje de pacientes que utilizó los SUH durante 1998 fue del 66,3 por ciento (55/83), correspondiendo a un número total de episodios de urgencias de 118 (media en los 55 pacientes de 2,7 ñ 1,51). El 51,7 por ciento de los episodios de urgencia fueron por iniciativa propia del paciente. Los 4 diagnósticos más frecuentes realizados en el SUh' fueron: problemas infecciosos, 19,5 por ciento (23/118); urgencias traumatológicas, 15,3 por ciento (18/118); problemas digestivos, 15,3 por ciento (18/118) y problemas relacionados con la FAV, 11,9 por ciento (14/118). El 30,5 por ciento (36/118) de los episodios de urgencias precisaron IH con una media de días de ingreso de 10,2 ñ 9,3 (2-42). Los problemas infecciosos fueron la primera causa de IH (36,1 por ciento) y los de mayor duración (12J.ñ 11,2 días). Fueron factores de riesgo de acudir repetidamente (más de 3 veces) a los SUH frente a no acudir: la edad (68,9 ñ 11,6 años vs 61,4 ñ 12,9 años) y los valores de hematocrito (31,6 ñ 4,14 vs 34,4 ñ3,93), hemoglobina (10,2 ñ 1,2 vs 11 ñ 1,3), dosis de EPO (166,3 ñ 94 unidades/kg/semana vs 109,7 ñ 77) y kT/V (0, 99 ñ 0,16 vs 1,11 ñ 0,19). Al comparar estos resultados con los de 1991 el porcentaje de pacientes que utilizó los SUH fue similar, 66,6 por ciento (pNS); el número medio de consultas fue mayor (2,99 ñ 1,96) que en 1998 (p < 0,006) existiendo una variación en los diagnósticos de urgencia entre 1998 y 1991; edema agudo de pulmón 1,7 por ciento vs 11,2 por ciento, respectivamente (p < 0,003); hiperpotasemia: 0,8 por ciento vs 7,9 por ciento (p < 0,009); digestivos 15,3 por ciento vs 4,5 por ciento (p < 0,008) e infecciosos: 19,5 por ciento vs 7,9 por ciento (p < 0,01).En conclusión, nuestro estudio aporta datos previamente no disponibles acerca de la epidemiología de las consultas de urgencia en el hospital de referencia de los pacientes de HD procedentes de un centro extrahospitalario vinculado. Los datos obtenidos, si bien limitados por el número reducido de pacientes, aportan información de utilidad práctica potencial para la posible reducción del número de consultas de urgencia hospitalaria por parte de los pacientes en diálisis. (AU)

Effect of cetrorelix on sperm morphology during migration through the epididymis in the cynomolgus macaque (Macaca fascicularis).

The importance of the cynomolgus monkey as a model for human reproductive medicine prompted this examination of epididymal sperm morphology. Computer-aided sperm morphological analysis was used for the first time to provide morphometric data on sperm heads as they traversed the epididymal duct of Macaca fascicularis. The duct was divided into six regions, starting close to the testis (proximal) and ending close to the vas deferens (distal). To determine the androgen-dependence of the changes, one group of animals received a GnRH-antagonist (Cetrorelix, Asta Medica, Frankfurt, Germany) to induce testicular regression and lower epididymal androgens, while a control group received only vehicle. Epididymides were removed 16 and 25 days after treatment, and sperm heads were analysed by a computer-assisted morphometric analyser. Cluster analysis revealed swollen sperm head cells in proximal regions 1 and 2 of the epididymis, but fewer such forms distally. Normal head shapes became the majority in region 4 and these underwent a gradual but statistically significant decrease in size (area, perimeter, length, width) and shape as they reached the distal regions. In the animals given Cetrorelix, sperm with swollen heads were found more distally than in the controls, although they were also never present in the distal cauda (region 6). Normal heads still became predominant in region 4 after 16 days treatment, and in region 6 after 25 days. The normal forms in the cauda epididymidis of treated animals were significantly larger than cells from control animals. We conclude that epididymal sperm maturation in the monkey is characterised by both a loss of sensitivity to distortion on air-drying, and by a decrease in sperm head size. The former, but not the latter, is attained by sperm in androgen-deficient epididymides from GnRH-antagonist-treated monkeys.

Morphological characterization of ejaculated cynomolgus monkey (Macaca fascicularis) sperm.

The aim of this study was to give reference values for the frequency of morphological sperm abnormalities present in the semen from non-experimental cynomolgus monkeys as well as for the dimensions of sperm heads. Spermatozoa from the liquid portion of electroejaculates from 14 cynomolgus monkeys were air-dried as smears, fixed, and stained with Harris's Haematoxylin and subjected to visual analysis of morphology and computer-aided analysis of ten morphometric variables. The majority (83%) of sperm were morphologically normal. Tail defects were the most common (11%), and showed the highest variation between individuals, the values ranging between 4 and 23%. Head abnormalities consisted of large, tapering, and amorphous forms but were not frequent (0.4%), the values ranging between 0 and 1.3%. Midpiece imperfections were found in all the individuals; the mean percentage was 5%, and the range varied between 3 and 9%. Tail plus midpiece was the only multiple abnormality observed, with a mean value of 1.5% and a range between 0 and 8%. The majority of these double defects consisted of a coiled tail together with a coiled midpiece. Mean values for the morphometric parameters characterizing sperm heads were as follows: area 17.2 microm2, perimeter 15.2 microm, length 5.8 microm, width 4.0 microm, L/W ratio 1.5, gray-level 98, ellipticity 0.2, first shape factor 0.9, second shape factor 1.4, and third shape factor 1.1. Overall coefficients of variation for the majority of parameters were below 7%, showing the great homogeneity in the dimensions of cynomolgus sperm heads. Most useful parameters for sperm characterization, according to their low variability, were perimeter, length, width, L/W ratio, and shape factors. Differences in these parameters were, however, observed between monkeys.

Standardization of sampling and staining methods for the morphometric evaluation of sperm heads in the Cynomolgus monkey (Macaca fascicularis) using computer-assisted image analysis.

Automated sperm morphology analysis (ASMA) technology has improved the assessment of sperm morphology, but the results depend on the use of adequate and standardized procedures. In this study the Sperm-Class Analyzer (SCA) ASMA system was used to assess sperm head morphometry in the Cynomolgus monkey and to evaluate the influence of sample size, intraslide variation, and the use of three staining techniques on the accuracy of image processing and sperm head morphometry. Haematoxylin is the staining technique of choice for Cynomolgus spermatozoa, as optimum contrast of sperm heads with the surrounding background allows efficient segmentation, i.e. sperm head boundary detection, making the image analysis process more accurate. The analysis of 100 spermatozoa is recommended since a larger sample size did not result in more accurate sperm head morphometry. There were no differences in either the percentage of correctly binarized sperm heads or sperm head dimensions among samples obtained from different zones of the slides, although differences in stain intensity (grey level) were detected. The measurements made on Haematoxylin, Diff-Quik and Hemacolor-stained slides yielded different values for all of the sperm head parameters under consideration. This result demonstrates that the procedures of fixation and staining significantly affect the dimensions of sperm heads.