Expiration Date Effect on Mechanical and Chemical Properties of Glass Ionomer Cements / Efecto de La Fecha de Vencimiento sobre las Propiedades Mecánicas y Químicas de los Cementos de Ionómero de Vidrio

The glass ionomer cements (GICs) is a generic name given to a group of materials widely used in clinical dentistry which if used after the specified expiration date, material properties may be affected. to evaluate the Vick ers microhardness, surface morphology and the energy dispersive X-ray microanalysis (EDX), of GICs with different expiration dates that were stored at room temperature. specimens of highly viscous glass ionomer cement (HVGIC) (Ketac Cem and Ketac Molar) and resin-modified glass ionomer cement (RMGIC) (Vitrebond) with different expiration dates (current, close to their expiration and expired) were prepared for Vickers microhardness test and scanning electronic microscopy (SEM) with EDX, measuring 5 mm in diameter and 2 mm length, per the manufacturer's instructions, in standard cylindrical teflon molds. For the comparison of obtained values, the ANOVA test was used, while Tukey test was used for the multiple comparisons. In all the GICs used, the microhardness decreased as the expiration date approached, finding a significant statistical differen ce (P<0.05) in Ketac Molar and Vitrebond. SEM sample analysis revealed similar cohesive cracks in all tested materials. The EDX analysis revealed the presence of the elements F, Al and Si in all GICs and Ca only in Ketac Molar and Ketac Cem. The elements were found in a higher atomic percentage in the GICs with an current date and in a lower percentage in those with an expired date. HVGIC and RMGIC with an expiration date finish and that were stored at room temperature, suffer significant physical and chemical changes, which could put doubts its clinical effectiveness.

El cemento de ionómero de vidrio (CIV) es un nombre genérico que se le da a un grupo de materiales ampliamente utilizados en odontología clínica que si se usan después de la fecha de vencimiento especificada, las propiedades del material pueden verse afectadas. evaluar la microdureza Vickers, la morfología superficial y el microanálisis de energía dispersa de rayos X (EDX), de CIV con diferentes fechas de caducidad almacenados a temperatura ambiente. Muestras de cemento de ionómero de vidrio de alta viscosidad (CIVAV) (Ketac Cem y Ketac Molar) y cemento de ionómero de vidrio modificado con resina (CIVMR) (Vitrebond) con diferentes fechas de vencimiento (vigente, próximo a su vencimiento y vencido) de 5 x 2 mm, fueron preparadas para microscopía electrónica de barrido (MEB) con EDX y microdureza Vickers, según las instrucciones del fabricante, en moldes de teflón cilíndricos estándar. Para la comparación de los valores obtenidos se utilizó la prueba ANOVA, mientras que para las comparaciones múltiples se utilizó la prueba de Tukey. En todos los CIV utilizados, la microdureza disminuyó a medida que se acercaba la fecha de vencimiento, encontrándose una diferencia estadística significativa (P <0.05) en Ketac Molar y Vitrebond. El análisis de la muestra en MEB reveló grietas cohesivas similares en todos los materiales probados. El análisis EDX reveló la presencia de los elementos F, Al y Si en todos los GIC y Ca solo en Ketac Molar y Ketac Cem. Los elementos se encontraron en mayor porcentaje atómico en los GIC con fecha vigente y en menor porcentaje en aquellos con una fecha vencida. Los CIVAV y CIVMR con fecha de caducidad vencida y que fueron alma- cenados a temperatura ambiente, sufrieron cambios físicos y químicos importantes, lo que podría poner en duda su efectividad clínica.

[Preferences in the format of questionnaires and use of the Internet by schoolchildren]. / Preferencias en el formato de cuestionarios y en el uso de Internet en escolares.

OBJECTIVES: To describe the preferences to complete questionnaires via the internet by schoolchildren, as well as to analyze the attitude towards the use of internet to communicate with health professionals. METHODS: Cross-sectional study of a school population in Palafolls (Barcelona, n=923) was conducted in October and November 2013. Participants completed both internet and paper versions on a single school day, in random order, and with at least an interval of 2 hours. Preferences to answer internet vs paper version were recorded, along with the willingness to share information with health professionals. Percentages of use preferences and attitudes were estimated, and logistic regression models were fitted to analyze the association with the preferences and willingness to share information with health professionals. RESULTS: Participation rates were 77% (n=715), of whom 42.4% (38.7 to 46.0) preferred the internet version, and 20.6% (17.6 to 23.6) the paper version. Older children (odds ratio [OR]=0.89, 0.84 to 0.95 for age), and those from families with secondary school (OR=0.63, 0.43 to 0.93), and university degree (OR=0.61, 0.38 to 0.97) were less likely to prefer the internet version, while boys (OR=1.55, 1.10 to 2.16) and those children reporting sedentary habits (OR=1.78, 1.06 to 3.0) were more likely to prefer the internet version. Those scoring higher quality of life (OR=1.03, 1.01-1.05) and not reporting sedentary habits (OR=0.33, 0.15 to 0.73) were factors associated with a positive attitude to share information with health professionals. CONCLUSIONS: Younger children prefer to use the internet. Although Internet use is very widespread, it is less used to communicate with health professionals.

Compatibility and stability of tramadol and dexamethasone in solution and its use in terminally ill patients.

BACKGROUND: Delivery of drug admixtures by continuous subcutaneous infusion is common practice in palliative medicine, but analytical confirmation of their compatibility and stability is not always available. OBJECTIVE: To study the compatibility and stability of tramadol hydrochloride and dexamethasone sodium phosphate combined in solution and to report on its use in terminally ill patients. METHOD: Twelve different solutions containing tramadol hydrochloride (8.33-33.33 mg/mL) and dexamethasone sodium phosphate (0.33-3.33 mg/mL) were prepared in saline and stored in polypropylene syringes for 5 days (25 degrees C). Analysis was performed on days 1, 3 and 5 days with simultaneous determination by HPLC. pH was measured at 0 and 5 days. Clinical performance was assessed retrospectively in six terminal-ill oncology patients. RESULTS: Maximum losses of 7% and 6% were observed for tramadol and dexamethasone. Pain was completely controlled in four patients. Local tolerance resulted in haematoma in three patients, which resolved by switching to a butterfly insertion site. CONCLUSION: Tramadol hydrochloride (100-400 mg/day) and dexamethasone sodium phosphate (4-40 mg/day) are stable for at least 5 days when combined in saline and stored at 25 degrees C. These results are only valid for the type of syringes and the specific commercial preparations tested.

Morphine, haloperidol and hyoscine N-butyl bromide combined in s.c. infusion solutions: compatibility and stability. Evaluation in terminal oncology patients.

The administration of drugs by subcutaneous infusion is routinely practiced in palliative medicine for the management of patients who are no longer able to take oral medication. It is common for two or more drugs to be combined in subcutaneous solutions. The combination of an opioid with other drugs (haloperiol lactate and hyoscine N-butyl bromide) can be very valuable. Unfortunately, the compatibility and stability of morphine hydrochloride, haloperidol lactate and hyoscine N-butyl bromide combined in the same solution has not yet been determined. Therefore, this study examined the stability of ternary solutions containing morphine HCl, haloperidol lactate and hyoscine N-butyl bromide at different dose ranges. Twelve different solutions were assessed for 15 days after preparation in polypropylene syringes using 0.9% saline as diluent. Triplicate syringes were stored at 25 degrees C. HPLC was the analytical technique used to measure morphine HCl, haloperidol lactate and hyoscine N-butyl bromide. Initial concentration ranges were 1.67-10.0 mg/ml for morphine HCl, 0.417-0.625 mg/ml for haloperidol lactate and, 5.0-6.67 mg/ml for hyoscine N-butyl bromide. All three drugs were very stable (>92.5%) when stored at 25 degrees C. The clinical performance of the admixture was retrospectively assessed in 21 terminal oncology patients. Total symptom control was achieved in 17 out of 21 patients with very good local tolerance.

Usefulness of urinary antigen detection by an immunochromatographic test for diagnosis of pneumococcal pneumonia in children.

We evaluated an immunochromatographic assay detecting pneumococcal antigen in urine samples from children diagnosed with pneumococcal pneumonia. The sensitivity and specificity of the immunochromatographic test with nonconcentrated urine (NCU) were 86.7 and 62.9%, respectively; with concentrated urine (CU), they were 100 and 11.7%, respectively. Pneumococcal antigen was also detected in 42.5% of NCU and 87.1% of CU samples from nasopharyngeal carriers. This is a nonspecific test for the diagnosis of pneumococcal pneumonia in children, particularly the very young.

The interrelations between disability and quality of life in patients with multiple sclerosis in the area of Bajo Aragon, Spain: a geographically based survey.

Multiple sclerosis (MS) is one of the most disabling diseases in young people, but the interrelation between disability and quality of life is poorly understood. As individual correlations between disability and the perspective of the patient may be weak in individual subjects, the purpose of our work was to analyze and correlate quality of life with neurologic impairment and disability in all patients with MS from the geographic area of the Bajo Aragón in the northeastern region of Spain. A total of 36 patients with a diagnosis of probable or clinically definite MS had an average age was 38.1 years (range,17-66 years). The majority of them were women (66.6%) and had relapsing-remitting forms (83.3%). The Minimal Record of Disability measured neurologic impairments, functional limitations, and handicaps. Quality of life was measured by the Functional Assessment of Multiple Sclerosis (FAMS) scale. Statistical analysis was performed with the Kruskal-Wallis nonparametric test and Pearson's coefficient of correlation. The mean EDSS of our cohort was 2.76 (range, 0-9). The mean FAMS score was 78.6 (SD, 52.5). We found that patients moderately or severely disabled (EDSS >3) showed a significantly decreased satisfaction in comparison with the nondisabled or mildly disabled ones. Disability and handicaps were significantly related to some items of FAMS: mobility, symptoms, and emotional well-being, but not with the remaining items: general contentment, thinking and fatigue, family and social well-being, and additional concerns. In comparison with patients from other population-based surveys, our patients were less disabled and enjoyed a better quality of life. Although we globally observed poorer quality of life in more disabled patients, the perspectives of the patients did not necessarily agree with disability scales in some domains of health. Quality of life should be included in the approach to MS patients if we want to provide cost-effective health care.

Effects of Light Intensity and Oxidized Nitrogen Sources on Hydrogen Production by Chlamydomonas reinhardii.

Chlamydomonas reinhardii cells, after a period of dark anaerobic adaptation, evolve H(2) not only in the dark but also in the light. Our results show that high irradiances impair prolonged H(2) evolution, while under low irradiances or darkness H(2) evolution proceeds for more than 50 hours. NO(3) (-) and NO(2) (-) suppress H(2) evolution both in the dark or under low irradiance. Apparently the cells prefer these oxidized nitrogen sources to protons as electron acceptors, since both NO(3) (-) and NO(2) (-) become reduced to NH(4) (+), which is excreted to the culture medium in high amounts. H(2) evolution started once these oxidized anions were largely depleted from the medium. Moreover, H(2) evolution was consistently associated with NH(4) (+) excretion even if NH(4) (+) was already present in high amounts in the medium. This observation indicates that the cells utilize not only their carbohydrate but also their protein reserves as sources of reducing power for H(2) evolution. This conclusion was supported by the observation that when nitrogen-starved cells were made anaerobic in a nitrogen-free medium, they not only evolved H(2) at very high rates but excreted concomitantly NH(4) (+) up to concentrations in the millimolar range.

Spectral Dependence of Photoregulation of Inorganic Nitrogen Metabolism in Chlamydomonas reinhardii.

The utilization of NO(3) (-) by green algae growing photoautotrophically under air, which are growth conditions close to their more habitual situations in nature, is associated with the excretion of NO(2) (-) and NH(4) (+) to the culture medium. The entire process is promoted by blue light and depends on photosynthetically active radiation for the required reducing equivalents. The stimulation of NO(3) (-) utilization and of its associated NO(2) (-) and NH(4) (+) excretions saturated at very low quantum fluxes of blue light (15 microequivalents per square meter per second) in Chlamydomonas reinhardii cells sparged with CO(2)-free air and irradiated with 50 microequivalents per square meter per second background red light. The wavelength dependence data of this stimulation correlated closely with the in situ photoactivation of nitrate reductase and also with the light induced increase in its biosynthesis and/or assembly.These results indicate that the photoregulation of inorganic N metabolism in C. reinhardii is mainly due to the blue light modulation of nitrate reductase. Although flavins are the most suitable candidates to act as physiological photoreceptors, the wavelength dependence data only show a major peak in the blue region between 400 and 500 nanometers.

[3H]prazosin binding to central nervous system regions of male and female rats.

Membranes were obtained from the pituitary gland and 13 cerebral regions of male rats and of females during two endocrinological states (estrous and diestrous-1), and assayed for alpha 1-receptor binding, using [3H]prazosin. At two [3H]prazosin concentrations, one near its binding dissociation constant and the other at a value at which the plateau was reached in the binding saturation curve (0.2 and 1.2 nM respectively), [3H]prazosin binding was highest to the frontal cortex, lowest to the spinal cord, and showed no differences in any region under any of the hormonal states tested. Results are discussed in relation to previously reported hormonal effects on alpha 1-receptors.

Effects of light quality, CO2 tensions and NO 3 (+-) concentrations on the inorganic nitrogen metabolism of Chlamydomonas reinhardii.

The blue light dependent utilization of nitrate by green algae under common air and high irradiances, besides its assimilatory nature, is associated with the release of NO2 (-) and NH4 (+) to the culture medium. If the CO2 content of the sparging air was increased up to 2%, previously excreted NO2 (-) and NH4 (+) were rapidly assimilated. When under air and high irradiances the cell density in the culture reached values corresponding to 25 µg Ch 1.ml(-1), no further growth was observed and the highest values of NO3 (-) consumption and NO2 (-) and NH4 (+) release were attained. Besides low CO2 tensions, increasing NO3 (-) concentrations in the medium stimulated the release of NO3 (-) and NH4 (+). Under CO2-free air the consumption of NO3 (-) and the release of NO2 (-) and NH4 (+) on a total N bases were almost stoichiometric and their rates saturated at much lower irradiances than under air. Under CO2-free air high rates of NO2 (-) release were only observed under the blue radiations that were effectively absorbed by photosynthetically active pigments, i.e. 460 nm, but not under 404 and 630 nm radiations. However, the simultaneous illumination of the cells with 404 and 630 nm monochromatic light showed a remarkable synergistic effect on NO2 (-) release.The results are discussed in terms of the close relationship between C and N metabolism, the photosynthetic reducing power required to convert NO inf3 (sup±) -N into R - NH2-N and the blue light activation of nitrate reductase.

In Vivo Blue-Light Activation of Chlamydomonas reinhardii Nitrate Reductase.

Chlamydomonas reinhardii cells, growing photoautotrophically under air, excreted to the culture medium much higher amounts of NO(2) (-) and NH(4) (+) under blue than under red light. Under similar conditions, but with NO(2) (-) as the only nitrogen source, the cells consumed NO(2) (-) and excreted NH(4) (+) at similar rates under blue and red light. In the presence of NO(3) (-) and air with 2% CO(2) (v/v), no excretion of NO(2) (-) and NH(4) (+) occurred and, moreover, if the bubbling air of the cells that were currently excreting NO(2) (-) and NH(4) (+) was enriched with 2% CO(2) (v/v), the previously excreted reduced nitrogen ions were rapidly reassimilated. The levels of total nitrate reductase and active nitrate reductase increased several times in the blue-light-irradiated cells growing on NO(3) (-) under air. When tungstate replaced molybdate in the medium (conditions that do not allow the formation of functional nitrate reductase), blue light activated most of the preformed inactive enzyme of the cells. Furthermore, nitrate reductase extracted from the cells in its inactive form was readily activated in vitro by blue light. It appears that under high irradiance (90 w m(-2)) and low CO(2) tensions, cells growing on NO(3) (-) or NO(2) (-) may not have sufficient carbon skeletons to incorporate all the photogenerated NH(4) (+). Because these cells should have high levels of reducing power, they might use NO(3) (-) or, in its absence, NO(2) (-) as terminal electron acceptors. The excretion of the products of NO(2) (-) and NH(4) (+) to the medium may provide a mechanism to control reductant level in the cells. Blue light is suggested as an important regulatory factor of this photorespiratory consumption of NO(3) (-) and possibly of the whole nitrogen metabolism in green algae.

Sex differences in alpha-adrenergic receptors in the rat brain.

[3H]Dihydroergocryptine ([3H]DHE) binding to several brain regions was studied in male and female rats, the latter in two different endocrinological states (estrous and diestrous-1). males showed higher [3H]DHE binding than females in hypothalamus, hippocampus and olfactory bulb, while females showed higher levels than males in spinal cord and visual cortex. In addition, intra-sex (that is, estrous versus diestrous-1) differences were detected in the cervico-thoracic spinal cord and cerebellum. Diestrous females presented higher values in both regions.