Large Hysteresis effect in Synchronization of Nanocontact Vortex Oscillators by Microwave Fields.

Current-induced vortex oscillations in an extended thin-film with point-contact geometry are considered. The synchronization of these oscillations with a microwave external magnetic field is investigated by a reduced order model that takes into account the dynamical effects associated with the significant deformation of the vortex structure produced by the current, which cannot be taken care of by using the standard rigid vortex theory. The complete phase diagram of the vortex oscillation dynamics is derived and it is shown that strong hysteretic behavior occurs in the synchronization with the external field. The complex nonlinear nature of the synchronization manifests itself also through the appearance of asymmetry in the locking frequency bands for moderate microwave field amplitudes. Predictions from the reduced order model are confirmed by full micromagnetic simulations.

Microbicide activity of clove essential oil (Eugenia caryophyllata)

Clove essential oil, used as an antiseptic in oral infections, inhibits Gram-negative and Gram-positive bacteria as well as yeast. The influence of clove essential oil concentration, temperature and organic matter, in the antimicrobial activity of clove essential oil, was studied in this paper, through the determination of bacterial death kinetics. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the microorganisms selected for a biological test. To determine the temperature effect, they were assayed at 21° and 37° C. The concentration coefficient was determined with 0.4%, and 0.2% of essential oil. The influence of the presence of organic matter was determined with 0.4% of essential oil. The results obtained demonstrated that Escherichia coli were more sensitive even though the essential oil exerted a satisfactory action in three cases. In the three microbial species, 0.4% of essential oil at 21º C have reduced the bacterial population in 5 logarithmic orders. Organic matter reduces the antibacterial activity even though the bactericide efficacy was not lost. Clove essential oil can be considered as a potential antimicrobial agent for external use.

Combined versus sequential diuretic treatment of ascites in non-azotaemic patients with cirrhosis: results of an open randomised clinical trial.

OBJECTIVE: The aim of the study was to compare sequential versus combined diuretic therapy in patients with cirrhosis, moderate ascites and without renal failure. DESIGN: One hundred patients were randomly assigned to the two diuretic treatments. The sequential treatment provided potassium canrenoate at the initial dose of 200 mg/day, then increased to 400 mg/day. Non-responders were treated with 400 mg/day of potassium canrenoate and furosemide at an initial dose of 50 mg/day, then increased to 150 mg/day. The combined treatment provided the initial dose of 200 mg/day of potassium canrenoate and 50 mg/day of furosemide, then increased to 400 mg/day and 150 mg/day, respectively. RESULTS: Most patients who received sequential treatment responded to potassium canrenoate alone (19% to 200 mg/day and 52.63% to 400 mg/day, respectively). Most patients who received the combined treatment responded to the first two steps (40% to the first step and 50% to the second, ie, 400 mg/day of potassium canrenoate plus 100 mg/day of furosemide). Adverse effects (38% vs 20%, p<0.05), in particular, hyperkalaemia (18% vs 4%, p<0.05), were more frequent in patients who received sequential therapy. As a consequence, the per cent of patients who resolved ascites without changing the effective diuretic step was higher in those who received the combined treatment (56% vs 76%, p<0.05). CONCLUSIONS: The combined diuretic treatment is preferable to the sequential one in the treatment of moderate ascites in patients with cirrhosis and without renal failure. NCT00741663. This work is an open randomised clinical trial.

Proving the antimicrobial spectrum of an amphoteric surfactant-sol-gel coating: a food-borne pathogen study.

An antimicrobial coating was evaluated in this work for its antimicrobial efficacy against common food-borne pathogens. Dodecyl-di(aminoethyl)-glycine, an organic disinfectant, was immobilized in a silicon oxide matrix to generate thin films over surfaces by means of the sol-gel process. Tetraethoxysilane was used as the polymeric precursor. No alteration of optical transparency on the covered surfaces was observed. Topographic images obtained with atomic force microscopy showed a homogeneous film with no additional roughness added by the polymer to the surface. The attenuated total reflectance-Fourier transform infrared spectral data showed the presence of dodecyl-di(aminoethyl)-glycine in the silicon oxide network after a normal cleaning procedure. The antimicrobial efficacy test was performed by exposing coated slides to suspensions of common food-borne pathogens: Escherichia coli, Staphyloccocus aureus, E. coli O157:H7, Salmonella typhi, S. cholerasuiss, Listeria innocua and L. monocytogenes. The coating activity was not only bacteriostatic but also bactericidal. The percent reduction of viable microorganism exposure over 24 h to the coated surface ranged between 99.5%, for the more resistant gram-positive bacteria, and over 99.999%, for most gram-negative bacteria. The silicon matrix itself did not account for any reduction of viable microbial, even more an increase was observed.

Enterotoxinas y enzimas estafilococcicas en presencia de aceites esenciales / Staphylococcal enterotoxins and enzymes in presence of essential oils

Nuestro objetivo fue investigar el efecto de concentraciones subinhibitorias de clavo, canela, y tomillo en el crecimiento de S aureus y en la producción de coagulasa, termonucleasa y enterotoxina. Con ese fi n se agregaron diferentes concentraciones de los aceites esenciales a Caldo Cerebro Corazón. La producción de enterotoxina en presencia y en ausencia de los aceites esenciales se determinó por la técnica de enzimoinmunoensayo (ELISA). Nuestros resultados indican que bajas concentraciones que no afectan el crecimiento, reducen la producción de la producción de las enzimas ensayadas y de enterotoxina El aceite esencial de tomillo es el que presenta mayor actividad pues al 0,04% produce la pérdida de la actividad de ambas enzimas y de la enterotoxicidad Esto es importante cuando consideramos su potencial aplicación en alimentos y en la industria farmacéutica

Our aim was to investigate the effect of subinhibitory concentrations of clove, cinnamon, and thyme essential oils on the growth of Staphylococcus aureus and its production of coagulase, thermonuclease and enterotoxin. Different concentrations of the essential oils were added to Brain Heart Infusion broth. The production of enterotoxin in the presence or absence of essential oils was estimated using the ELISA technique. Our results indicate that a lower concentration did not affect the growth S. aureus but reduced the production of metabolites. Thyme oil presents the most signifi cant effect, inhibiting the activity of both enzymes and the production of enterotoxin with 0,04%. There is a renewed interest in the potential application of these essential oils in the food and pharmaceutical industries to control staphylococcal poisoning

Antimicrobial activity on glass materials subject to disinfectant xerogel coating.

The antimicrobial compound dodecyl-di(aminoethyl)-glycine was immobilized in a silicon oxide xerogel matrix and used for glass surface coating. Coated glasses were tested for surface antimicrobial activity. The utilization of tetraethoxysilane (TEOS) as a silicon oxide polymer precursor, using the dip-coating process, allowed for the generation of transparent thin films over glass surfaces. Different concentrations of the antimicrobial compound were used to generate the coatings. The presence of dodecyl-di(aminoethyl)-glycine on coated and uncoated slides was analyzed by FT-IR spectra. Coated glass slides were exposed to suspensions of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus for 24 h. Surface contamination was evaluated by the microbial plate count technique. When antimicrobial-coated glasses were compared with antimicrobial-free coated glasses, the former showed greater than 99% reduction of colony-forming units (cfu) for E. coli and P. aeruginosa, when 1% of antimicrobial was present in the coating solution. The same percentage of reduction for S. aureus was achieved when 1.5% of the antimicrobial was present in the coating solution. In a direct inhibition test on agar plates, no inhibitory zone was observed, indicating that the antimicrobial did not diffuse into the media.

Immune response in relation to zinc status, sex and antioxidant defence in Italian elderly population: the ZENITH study.

OBJECTIVE: Evaluation of some immune markers in Italian elderly population in relation to zinc status, gender and antioxidant defence. DESIGN: Observational study. SETTING: Italian population. SUBJECTS: Apparently healthy, free-living subjects, 56 men and 52 women, aged 70-85 y, enrolled in Italy. METHODS: Lymphocytes were unstimulated or stimulated with the mitogen phytohemoagglutinin (PHA). The proliferative capacity was measured as incorporation of [3H]-thymidine and reported as stimulation index (SI). Cytokine secretion by lymphocytes was determined by ELISA. The antioxidant enzyme activities were measured using commercial kits. RESULTS: Dietary zinc intake, as well as zinc in serum, red blood cells and urine were on the normal range of values and did not show any difference between men and women. The proliferative response showed a high variability without significant differences between men and women. The amount of secreted pro- and anti-inflammatory cytokines was similar in men and women. No differences were found in the activity of antioxidant enzymes in lymphocytes, namely superoxide dismutase, glutathione peroxidase and catalase, between men and women. An association between SI and serum zinc level in men was found. SI resulted negatively correlated with interleukin (IL)-1beta (R2 = 0.036 and P = 0.012) and IL-10 (R2 = 0.34 and P = 0.040) only in men. IL-10 of PHA-stimulated lymphocytes was negatively correlated with red blood zinc in men (R2 = 0.41 and P = 0.008), while IL-10 of unstimulated and PHA-stimulated lymphocytes were negatively correlated with serum zinc in women (R2 = 0.38 and P = 0.020; R2 = 0.31 and P = 0.040, respectively). No correlation was observed between immune markers and antioxidant enzyme activities. CONCLUSIONS: Only weak differences on immune response between men and women were observed. However, zinc status appears to have more influence on the ability of lymphocytes to proliferate in men than in women.

Magnetization switching and microwave oscillations in nanomagnets driven by spin-polarized currents.

A novel theoretical approach to magnetization dynamics driven by spin-polarized currents is presented. Complete stability diagrams are obtained for the case where spin torques and external magnetic fields are simultaneously present. Quantitative predictions are made for the critical currents and fields inducing magnetization switching, for the amplitude and frequency of magnetization self-oscillations, and for the conditions leading to hysteretic transitions between self-oscillations and stationary states.

What is the scope of bioluminiscence in pharmaceutical clean rooms monitoring?

By means of bioluminiscence ATP present in a sample can be quantified. Thus, it would be a method able to evaluate microbiological or organic matter (from vegetal or animal origin) contamination. The present work analyzes the possibility to assess--from the microbiological point of view--the air of pharmaceutical clean rooms by means of bioluminiscence, using the luminomiter HY-LITE 2 [Merck]. It is thought that the use of this methodology versus microbiological classical methods, will allow to obtain results in the working day. Classical methods demand a minimum of 72 hs incubation to read results. But the real conclusion is that with the used technology, it is not possible to evaluate microbiologically the air of pharmaceutical clean rooms.

Induction of apoptosis in human pancreatic cancer cells by docosahexaenoic acid.

Polyunsaturated fatty acids have been indicated to induce anti-proliferative and/or apoptotic effects in various tumor cells. We showed that, at a 200- micro M concentration, both alpha-linoleic (18:2 n-6; LA) or docosahexaenoic (22:6 n-3; DHA) acid inhibited cell growth, while only DHA induced apoptosis in the human Paca-44 pancreatic cancer cell line. Investigating the mechanism underlying DHA-induced apoptosis, we showed that DHA induced a rapid and dramatic (>60%) intracellular depletion of reduced glutathione (GSH), without affecting oxidized glutathione (GSSG). Moreover, using two specific inhibitors of carrier-mediated GSH extrusion, cystathionine or methionine, we observed that GSH depletion occurred via an active GSH extrusion, and that inhibition of GSH efflux completely reversed apoptosis. These results provide the first evidence for a possible causative role of GSH depletion in DHA-induced apoptosis.

Implantação do programa de fitoterapia "Verde Vida" na secretaria de saúde de Maringá (2000-2003)

Há muitos anos, tenta-se implantar a fitoterapia no município de Maringá, o que só foi possível em 2000, com a criação de uma comissão específica, definição das plantas segundo critérios epidemiológicos, literatura disponível e adoção do formato de farmácia de manipulação. Foram padronizados os fitoterápicos nas formas de infusão (espinheira-santa, guaco, cavalinha, hortelã e funcho), gel (própolis e calêndula) e em cápsulas gelatinosas duras (valeriana). Encontrou-se problemas com fornecedores, com diversos lotes insatisfatórios quanto à qualidade, mas ao longo do tempo o programa foi muito bem aceito. Nestes três anos de funcionamento, já foram dispensados mais de 50.000 unidades de produtos, com destaque à aceitação e eficácia da valeriana como ansiolitico, dos géis de própolis e calendula como antimicrobiano e cicatrizante, da espinheirasanta em gastrites e úlceras e do guaco como broncodilator e expectorante. Confirma-se, assim, o valor da fitoterapia no apoio às atividades básicas de saúde.

There are many years, it tries to implant the phytotherapy in the municipal district of Maringá. That implantation was only possible in 2000, with the creation of specific commission, definition of the plants according to epidemic criteria and available literature, and adoption of the format of manipulation drugstore. We have standardized the phytotherapics in the infusion forms (espinheira-santa, guaco, cavalinha, mint and fennel), gel (própolis and calendula) and in hard gelatinous capsules (valerian). There were problems with suppliers, with several unsatisfactory lots as for the quality, but along the time the program was very well accepted. On these three years of operation, there were already released more than 50.000 units of products, with prominence to the acceptance and effectiveness of the valerian as ansiolitic, two gels of propolis and calendula as antimicrobial and healing, of the espinheirasanta in gastritis and ulcers and of the guaco as broncodilator and expectorant. It is confirmed, like this, the value of the phytotherapy in the support to the basic activities of health.

Microesferas de alginato con Bacillus subtilis / Alginate microspheres of Bacillus subtilis

La microencapsulación de organismos ha sido considerada como una alternativa de inmovilización de células, a fin de que éstas puedan ejercer sus funciones en forma gradual. El objetivo del presente estudio fue elaborar microesferas de Bacillus subtilis ya sea en forma esporulada como vegetativa.Microesferas de Bacillus subtilis son preparadas utilizando alginato de sodio. Algunas propiedades típicas del sistema microencapsulado, tales como contenido de microorganismos, tamaño de partícula y tiempo de germinación han sido estudiados. Las microesferas se prepararon mediante el método de coaservación-separación de fases, utilizando una etapa intermedia de emulsión múltiple. Las condiciones de preparación han sido lo suficientemente benignas para no producir cambios en las propiedades biológicas generales del sistema, pero con la protección que le otorga la matriz del hidrogel, la cual evita la directa comunicación con el medio externo.La viabilidad demostrada por las microesferas con las formas esporuladas fue significativamente superior a las de las formas vegetativas (AU)

Efectividad de clorogenos destinadosa agua de consumo / Efectiveness of chlorogenic products destinated to drinking waters

Se propone una metodología para la evaluación de productos clorógenos destinados a la desinfección de aguas para consumo, utilizando materia orgánica para simular el consumo de cloro que tienen las aguas no tratadas. Se evaluó el comportamiento de suspensión de levadura de cerveza, peptona y extracto de levadura frente a dosis usuales (10 mg/L, como cloro total) de comprimidos de la sal disódica de la dicloro-S-triazina-triona. Como comparación se utilizó agua de río.Se determinó la concentración de cada sustancia orgánica que despues de 30 minutos dejó 0,1 mg/L de cloro libre en la solución de ensayo. Posteriormente se ensayó microbiologicamente la efectividad del clorógeno en presencia de dichas sustancias según metodología AFNOR (AU)

A simple procedure for determining the presence and concentration of Listeria monocytogenes in dairy products.

This paper presents a simple method for determining both the presence and concentration of Listeria monocytogenes in dairy products. The method involves application of the Most Probable Number (MPN) technique and enrichment of a 25 g sample. Our tests showed that the MPN correlates with the Colony Forming Units (CFU), and estimated concentrations of as low as 1 bacterium/gr or less. We also studied the influence of Listeria innocua as an accompanying flora. We detected L. monocytogenes, even in the presence of concentrations of 4 times as much L. innocua. Nonetheless, L. monocytogenes could not be detected when the concentration of L. innocua surpassed 90%.

Influencia de diferentes derivados lácteos sobre el crecimiento de Listeria monocytogenes en medios selectivos / Influence of different dairy products on the growth kinetic of Listeria monocytogenes

Se estudió la influencia del añadido de crema de leche y leche parcialmente descremada sobre la cinética de crecimiento de Listeria monocytogenes en caldos de enriquecimiento para listerias, conteniendo diferentes concentraciones de acriflavina (15 y 7,5 mg/l). El crecimiento de Listeria monocytogenes en los caldos de enriquecimiento sufrió un retardo atribuible, al menos parcialmente, a la presencia de acriflavina. El añadido de crema de leche o leche parcialmente descremada al caldo de enriquecimiento que contiene 7,5 mg/l de acriflavina produjo un alargamiento de la fase de adaptación, pero las cosechas máximas alcanzadas a las 48 h no mostraron diferencias significativas. En presencia de 15 mg/l de acriflavina, se observó una pérdida inicial de la viabilidad de los cultivos, que fue potenciada por el agregado de crema de leche o leche parcialmente descremada al caldo de enriquecimiento. Además, la leche descremada produjo una disminución de la velocidad máxima de crecimiento que impidió alcanzar la cosecha máxima dentro de las 48 h. Los resultados obtenidos sugieren la necesidad de validar la metodología de recuperación de L. monocytogenes para cada producto, pues la eficiencia de recuperación podría ser afectada por la composición del mismo, sobre todo cuando la carga microbiana es baja

[Effect of different dairy products on the growth of Listeria monocytogenes in selective media]. / Influencia de diferentes derivados lácteos sobre el crecimiento de Listeria monocytogenes en medios selectivos.

We have studied the influence of the incorporation of milk cream and skim milk on the growth kinetic of Listeria monocytogenes in listeria enrichment broth with 15 mg/l or 7.5 mg/l of acriflavine. Acriflavine was responsible, at least partially, for delayed growth of Listeria monocytogenes in the enrichment broths. A longer lag phase of the growth was produced by the addition of milk cream or skim milk to the enrichment broth containing 7.5 mg/l of acriflavine. However, the maximum population obtained at 48 h did not show significant differences. In the presence of 15 mg/l of acriflavine, we observed a decrease of the viable counts during the early phase of the growth cycle, which was enhanced by the addition of milk cream or skim milk. Moreover, the maximum growth rate was reduced by the addition of skim milk and maximum population was not reached at 48 h. These results suggest the need to validate the methodology of recuperation of Listeria monocytogenes from each dairy product, since its efficiency may be affected by product composition, specially when the sample biocharge is low.

Inhibition of human low-density lipoprotein oxidation by caffeic acid and other hydroxycinnamic acid derivatives.

The antioxidant activity of the major phenols derived from hydroxycinnamic acid (caffeic, ferulic, and p-coumaric acids) on in vitro LDL oxidation was screened, using Cu2+ as catalyst. The presence of the second phenolic hydroxy group enhanced the inhibitory effect of these compounds. In fact, at 5 microM concentration, only caffeic acid completely protected LDL from modification as measured as conjugated dienes formation and apo B-100 fragmentation, also preserving alpha-tocopherol. The effect of caffeic acid in inhibiting LDL oxidative modification induced by three different oxidant systems was tested. Using both Cu2+ and 2,2'-azobis (2-amidinopropane)-hydrochloride (AAPH), the inhibitory effect of caffeic acid was dose-dependent. Yet, the better protection was achieved in the metal-ion dependent system. Also the murine macrophages-mediated LDL oxidation was efficiently inhibited by 5 microM caffeic acid. UV-VIS spectra of caffeic acid incubated with cupric ions show the formation of a caffeic acid:copper complex, responsible for a transient chelating activity. This mechanism, coupled with its free radical scavenging property, accounts for the higher inhibitory activity exhibited by caffeic in Cu(2+)-catalyzed reaction.

[Water disinfection: comparative activities of ozone and chlorine on a wide spectrum of bacteria]. / Desinfección de agua: acción comparativa del ozono y cloro sobre un amplio espectro bacteriano.

Ozone and chlorine are agents that disinfect by destroying, neutralizing or inhibiting the growth of pathogenic microorganisms. The treatment of drinking water with ozone has shown to be more efficient against spores of Bacillus subtilis. It was observed that the ozone already in dose of 0.35 mg/l produced the reduction of at least 5 log in populations of approximately 1 x 10(6) cells/ml of Escherichia coli, Vibrio cholerae, Salmonella typhi, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Listeria monocytogenes and Staphylococcus aureus. With a dose of 0.50 mg/l of chlorine, the reduction was much smaller for the tested microorganisms (except Vibrio cholerae), while the effect of 2 mg/l of chlorine was similar to the ozone treatment. For spores of Bacillus subtilis, the reduction observed with ozone concentrations of 0.35 and 0.70 mg/l was of almost 3 log, while no considerable effect was obtained with chlorine in the tested conditions. Our results have shown that both disinfectans were consumed during the treatment period, probably because of the own water demand and the added bacterial mass.

Desinfección de agua: acción comparativa del ozono y cloro sobre un amplio espectro bacteriano / [Water disinfection: comparative activities of ozone and chlorine on a wide spectrum of bacteria]

Ozone and chlorine are agents that disinfect by destroying, neutralizing or inhibiting the growth of pathogenic microorganisms. The treatment of drinking water with ozone has shown to be more efficient against spores of Bacillus subtilis. It was observed that the ozone already in dose of 0.35 mg/l produced the reduction of at least 5 log in populations of approximately 1 x 10(6) cells/ml of Escherichia coli, Vibrio cholerae, Salmonella typhi, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Listeria monocytogenes and Staphylococcus aureus. With a dose of 0.50 mg/l of chlorine, the reduction was much smaller for the tested microorganisms (except Vibrio cholerae), while the effect of 2 mg/l of chlorine was similar to the ozone treatment. For spores of Bacillus subtilis, the reduction observed with ozone concentrations of 0.35 and 0.70 mg/l was of almost 3 log, while no considerable effect was obtained with chlorine in the tested conditions. Our results have shown that both disinfectans were consumed during the treatment period, probably because of the own water demand and the added bacterial mass.