Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 24
Filter
1.
Pediatr Res ; 93(5): 1294-1301, 2023 04.
Article in English | MEDLINE | ID: mdl-35915238

ABSTRACT

BACKGROUND: Waist-to-height ratio (WHtR) predicts abdominal fat and cardiometabolic risk. In children with obesity, the most adequate cut-off to predict cardiometabolic risk as well as its ability to predict risk changes over time has not been tested. Our aim was to define an appropriate WHtR cut-off to predict cardiometabolic risk in children with obesity, and to analyze its ability to predict changes in cardiometabolic risk over time. METHODS: This is an observational prospective study secondary to the OBEMAT2.0 trial. We included data from 218 participants (8-15 years) who attended baseline and final visits (12 months later). The main outcome measure was a cardiometabolic risk score derived from blood pressure, lipoproteins, and HOMA index of insulin resistance. RESULTS: The optimal cut-off to predict the cardiometabolic risk score was WHtR ≥0.55 with an area under the curve of 0.675 (95% CI: 0.589-0.760) at baseline and 0.682 (95% CI: 0.585-0.779) at the final visit. Multivariate models for repeated measures showed that changes in cardiometabolic risk were significantly associated with changes in WHtR. CONCLUSION: This study confirms the clinical utility of WHtR to predict changes in cardiometabolic risk over time in children with obesity. The most accurate cut-off to predict cardiometabolic risk in children with obesity was WHtR ≥0.55. IMPACT: In children, there is no consensus on a unique WHtR cut-off to predict cardiometabolic risk. The present work provides sufficient evidence to support the use of the 0.55 boundary. We have a large sample of children with obesity, with whom we compared the previously proposed boundaries according to cardiometabolic risk, and we found the optimal WHtR cut-off to predict it. We also analyzed if a reduction in the WHtR was associated with an improvement in their cardiometabolic profile.


Subject(s)
Cardiovascular Diseases , Metabolic Syndrome , Humans , Child , Metabolic Syndrome/complications , Metabolic Syndrome/diagnosis , Prospective Studies , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/complications , Body Mass Index , Obesity/complications , Obesity/diagnosis , Risk Factors , Waist Circumference
2.
Arch. argent. pediatr ; 120(6): e264-e267, dic. 2022.
Article in Spanish | LILACS, BINACIS | ID: biblio-1399710

ABSTRACT

La infección por estreptococo ß-hemolítico del grupo B o Streptococcus agalactiae puede causar morbilidad grave y mortalidad en los recién nacidos, especialmente en prematuros. Las estrategias de prevención actuales han sido eficaces en reducir la frecuencia de sepsis neonatal temprana ocasionada por transmisión vertical. La incidencia de sepsis tardía por dicho microrganismo no se ha modificado y la vía de infección es menos clara. En niños amamantados, la transmisión a través de la leche materna es posible. Se presentan tres casos de infección tardía por estreptococo ß-hemolítico del grupo B en recién nacidos prematuros alimentados con leche materna cuyas madres tenían mastitis. En todos los casos, tanto en el cultivo de la leche materna como en los hemocultivos de los neonatos se desarrolló el mismo microrganismo.


Group B ß-hemolytic Streptococcus or Streptococcus agalactiae is a major cause of morbidity and mortality in neonates, especially in premature infants. Current prevention strategies have been effective in reducing the frequency of early onset neonatal sepsis caused by vertical transmission. The incidence of late onset sepsis due to this microorganism has not changed and the route of infection is less clear. In breastfed infants, transmission through breast milk is possible. We report three cases of late group B ß-hemolytic streptococcal infection in breastfed preterm infants whose mothers had mastitis. In all cases, both the breast milk culture and the blood cultures of the neonates developed the same microorganism.


Subject(s)
Humans , Female , Infant, Newborn , Streptococcal Infections/diagnosis , Streptococcal Infections/epidemiology , Streptococcus agalactiae , Infant, Premature , Infectious Disease Transmission, Vertical/prevention & control , Milk, Human
3.
Arch Argent Pediatr ; 120(6): e264-e267, 2022 12.
Article in Spanish | MEDLINE | ID: mdl-36374063

ABSTRACT

Group B ß-hemolytic Streptococcus or Streptococcus agalactiae is a major cause of morbidity and mortality in neonates, especially in premature infants. Current prevention strategies have been effective in reducing the frequency of early onset neonatal sepsis caused by vertical transmission. The incidence of late onset sepsis due to this microorganism has not changed and the route of infection is less clear. In breastfed infants, transmission through breast milk is possible. We report three cases of late group B ß-hemolytic streptococcal infection in breastfed preterm infants whose mothers had mastitis. In all cases, both the breast milk culture and the blood cultures of the neonates developed the same microorganism.


La infección por estreptococo ß-hemolítico del grupo B o Streptococcus agalactiae puede causar morbilidad grave y mortalidad en los recién nacidos, especialmente en prematuros. Las estrategias de prevención actuales han sido eficaces en reducir la frecuencia de sepsis neonatal temprana ocasionada por transmisión vertical. La incidencia de sepsis tardía por dicho microrganismo no se ha modificado y la vía de infección es menos clara. En niños amamantados, la transmisión a través de la leche materna es posible. Se presentan tres casos de infección tardía por estreptococo ß-hemolítico del grupo B en recién nacidos prematuros alimentados con leche materna cuyas madres tenían mastitis. En todos los casos, tanto en el cultivo de la leche materna como en los hemocultivos de los neonatos se desarrolló el mismo microrganismo.


Subject(s)
Streptococcal Infections , Streptococcus agalactiae , Humans , Infant, Newborn , Infant , Female , Milk, Human , Infant, Premature , Streptococcal Infections/diagnosis , Streptococcal Infections/epidemiology , Infectious Disease Transmission, Vertical/prevention & control
4.
Materials (Basel) ; 15(17)2022 Aug 29.
Article in English | MEDLINE | ID: mdl-36079338

ABSTRACT

We present a novel Ti64/20Ag highly porous composite fabricated by powder metallurgy for biomedical applications and provide an insight into its microstructure and mechanical proprieties. In this work, the Ti64/20Ag highly porous composites were successfully fabricated by the space holder technique and consolidated by liquid phase sintering, at lower temperatures than the ones used for Ti64 materials. The sintering densification was evaluated by dilatometry tests and the microstructural characterization and porosity features were determined by scanning electron microscopy and computed microtomography. Permeability was estimated by numerical simulations on the 3D real microstructure. Mechanical properties were evaluated by simple compression tests. Densification was achieved by interparticle pore filling with liquid Ag that does not drain to the large pores, with additional densification due to the macroscopical deformation of large pores. Pore characteristics are closely linked to the pore formers and the permeability was highly increased by increasing the pore volume fraction, mainly because the connectivity was improved. As expected, with the increase in porosity, the mechanical properties decreased. These results permitted us to gain a greater understanding of the microstructure and to confirm that we developed a promising Ti64/20Ag composite, showing E of 7.4 GPa, σy of 123 MPa and permeability of 3.93 × 10-11 m2. Enhanced adaptability and antibacterial proprieties due to Ag were obtained for bone implant applications.

5.
Clin Nutr ; 40(6): 4132-4139, 2021 06.
Article in English | MEDLINE | ID: mdl-33610417

ABSTRACT

BACKGROUND & AIMS: The aim was to generate a predictive equation to assess body composition (BC) in children with obesity using bioimpedance (BIA), and avoid bias produced by different density levels of fat free mass (FFM) in this population. METHODS: This was a cross-sectional validation study using baseline data from a randomized intervention trial to treat childhood obesity. Participants were 8 to 14y (n = 315), underwent assessments on anthropometry and BC through Air Displacement Plethysmography (ADP), Dual X-Ray Absorptiometry and BIA. They were divided into a training (n = 249) and a testing subset (n = 66). In addition, the testing subset underwent a total body water assessment using deuterium dilution, and thus obtained results for the 4-compartment model (4C). A new equation to estimate FFM was created from the BIA outputs by comparison to a validated model of ADP adjusted by FFM density in the training subset. The equation was validated against 4C in the testing subset. As reference, the outputs from the BIA device were also compared to 4C. RESULTS: The predictive equation reduced the bias from the BIA outputs from 14.1% (95%CI: 12.7, 15.4) to 4.6% (95%CI: 3.8, 5.4) for FFM and from 18.4% (95%CI: 16.9, 19.9) to 6.4% (95% CI: 5.3, 7.4) for FM. Bland-Altman plots revealed that the new equation significantly improved the agreement with 4C; furthermore, the observed trend to increase the degree of bias with increasing FM and FFM also disappeared. CONCLUSION: The new predictive equation increases the precision of BC assessment using BIA in children with obesity.


Subject(s)
Body Composition , Electric Impedance , Indicator Dilution Techniques/statistics & numerical data , Pediatric Obesity/diagnosis , Plethysmography/statistics & numerical data , Absorptiometry, Photon , Adolescent , Anthropometry , Body Water , Child , Cross-Sectional Studies , Female , Humans , Male , Predictive Value of Tests , Randomized Controlled Trials as Topic , Reproducibility of Results
6.
Arch. argent. pediatr ; 115(5): 490-493, oct. 2017. graf, tab
Article in English, Spanish | LILACS, BINACIS | ID: biblio-1038384

ABSTRACT

Introducción. La autopsia neonatal es un valioso método diagnóstico y esencial para el asesoramiento familiar sobre futuros embarazos. Población y métodos. Estudio retrospectivo que incluyó todas las autopsias de neonatos fallecidos en la Clínica y Maternidad Suizo Argentina desde enero de 1998 a diciembre de 2006. Se determinó la tasa de autopsias y se compararon los diagnósticos obtenidos de las historias clínicas con los resultados de estas. Resultados. Sobre el total de 227 niños fallecidos,se realizaron 135 autopsias (tasa de 59,5%). En el 25%,la concordancia fue completa. En el 26%, se halló nueva información con significativa implicancia para el asesoramiento genético. Conclusiones. La tasa de autopsias fue del 59,5%. La correlación anatomoclínica y sus insospechados hallazgos con implicancia para el asesoramiento genético muestran la importancia de la práctica sistemática de la autopsia neonatal.


Introduction. Neonatal autopsy is a valuable, critical diagnostic method to provide genetic counseling for future pregnancies. Population and methods. Retrospective study including all neonatal autopsies performed on deceased neonates at Clínica y Maternidad Suizo Argentina between January 1998 and December 2006. The rate of autopsies was established; the diagnosis indicated in the medical record was compared to autopsy findings. Results. Out of 227 deceased infants, 135 autopsies were performed (rate: 59.5%). Concordance was complete in 25% of autopsies. New information was found in 26%, which had significant implications for genetic counseling. Conclusions. The rate of autopsies was 59.5%. Pathological and clinical correlation and unsuspected findings with implications for genetic counseling demonstrate the relevance of performing neonatal autopsies systematically.


Subject(s)
Humans , Infant, Newborn , Autopsy , Infant, Newborn , Correlation of Data , Genetic Counseling
7.
Arch Argent Pediatr ; 115(5): 490-492, 2017 10 01.
Article in English, Spanish | MEDLINE | ID: mdl-28895697

ABSTRACT

INTRODUCTION: Neonatal autopsy is a valuable, critical diagnostic method to provide genetic counseling for future pregnancies. POPULATION AND METHODS: Retrospective study including all neonatal autopsies performed on deceased neonates at Clínica y Maternidad Suizo Argentina between January 1998 and December 2006. The rate of autopsies was established; the diagnosis indicated in the medical record was compared to autopsy findings. RESULTS: Out of 227 deceased infants, 135 autopsies were performed (rate: 59.5%). Concordance was complete in 25% of autopsies. New information was found in 26%, which had significant implications for genetic counseling. CONCLUSIONS: The rate of autopsies was 59.5%. Pathological and clinical correlation and unsuspected findings with implications for genetic counseling demonstrate the relevance of performing neonatal autopsies systematically.


INTRODUCCIÓN: La autopsia neonatal es un valioso método diagnóstico y esencial para el asesoramiento familiar sobre futuros embarazos. POBLACIÓN Y MÉTODOS: Estudio retrospectivo que incluyó todas las autopsias de neonatos fallecidos en la Clínica y Maternidad Suizo Argentina desde enero de 1998 a diciembre de 2006. Se determinó la tasa de autopsias y se compararon los diagnósticos obtenidos de las historias clínicas con los resultados de estas. RESULTADOS: Sobre el total de 227 niños fallecidos,se realizaron 135 autopsias (tasa de 59,5%). En el 25%,la concordancia fue completa. En el 26%, se halló nueva información con significativa implicancia para el asesoramiento genético. CONCLUSIONES: La tasa de autopsias fue del 59,5%. La correlación anatomoclínica y sus insospechados hallazgos con implicancia para el asesoramiento genético muestran la importancia de la práctica sistemática de la autopsia neonatal.


Subject(s)
Autopsy/statistics & numerical data , Infant, Newborn, Diseases/pathology , Humans , Infant, Newborn , Retrospective Studies
8.
Ginecol Obstet Mex ; 83(9): 545-50, 2015 Sep.
Article in Spanish | MEDLINE | ID: mdl-26591043

ABSTRACT

UNLABELLED: Ovarian ectopic pregnancy is only 3% of all ectopic, with an incidence of 1:7,000-40,000. In the last 10 years, it has been a rise in incidence. Most patients have vaginal bleeding, abdominal pain and shock data. Less than 300-400 cases are reported in the literature. CASE: We present the case of a woman with ovarian ectopic pregnancy of 12 weeks of gestation, who have not suggestive clinical signs and whose diagnosis was incidental despite having a regular prenatal ultrasound. CONCLUSION: Ovarian pregnancy is a rare presentation; diagnosis is difficult and often suggested by clinical data, when clinical data fail, more studies are needed to integrate the diagnosis.


Subject(s)
Pregnancy, Ovarian/diagnosis , Adult , Female , Humans , Pregnancy
9.
ScientificWorldJournal ; 2014: 514204, 2014.
Article in English | MEDLINE | ID: mdl-25610907

ABSTRACT

We evaluated changes of different soil nitrogen forms (total N, available ammonium and nitrate, total N in microbial biomass, and soil N mineralization) after conversion of semideciduous dry tropical forest in 5- and 18-year-old pastures (YP and OP, resp.) in the western Llanos of Venezuela. This evaluation was made at early rainy season, at end rainy season, and during dry season. With few exceptions, no significant differences were detected in the total N in the three study sites. Compared to forest soils, YP showed ammonium losses from 4.2 to 62.9% and nitrate losses from 20.0 to 77.8%, depending on the season of the year. In OP, the ammonium content increased from 50.0 to 69.0% at the end of the rainy season and decreased during the dry season between 25.0 and 55.5%, whereas the nitrate content increased significantly at early rainy season. The net mineralization and the potentially mineralizable N were significantly higher (P < 0.05) in OP than in forest and YP, which would indicate a better quality of the substrate in OP for mineralization. The mineralization rate constant was higher in YP than in forest and OP. This could be associated with a reduced capacity of these soils to preserve the available nitrogen.


Subject(s)
Forests , Nitrogen/analysis , Seasons , Soil/chemistry , Ammonium Compounds/analysis , Forestry , Rain , Venezuela
10.
Rev Electron ; 38(6)jul. 2013. tab, graf
Article in Spanish | CUMED | ID: cum-54172

ABSTRACT

Se realizó una investigación observacional, descriptiva y retrospectiva, en la Unidad de Cuidados Intermedios del Hospital General Docente Dr. Ernesto Guevara de la Serna de la provincia Las Tunas, durante el período comprendido entre enero de 2007 a diciembre de 2011, con el objetivo de caracterizar el comportamiento de las infecciones nosocomiales. La muestra la constituyeron los 390 pacientes con infección hospitalaria, se identificaron y describieron algunas tasas y variables de interés. Se utilizaron fuentes primarias para la obtención de la información, y los datos fueron procesados utilizando la estadística descriptiva mediante el análisis porcentual. La Tasa de Infección Hospitalaria Global tuvo un comportamiento que no se corresponde con la media nacional, la tasa de mortalidad está disminuida, respecto al indicador establecido; según las localizaciones, el sistema respiratorio fue el más afectado; el índice de positividad de las muestras fue elevado; la cepa del germen predominante fue el Citrobacter diversus (AU)


A retrospective, descriptive and observational research was carried out at the Intermediate Care Unit of Dr Ernesto Guevara de la Serna General Teaching Hospital of Las Tunas, from January, 2007 to December, 2011. The study aimed at describing the behavior of nosocomial infections. The sample included the 390 patients with hospital infection. Some rates and variables of interest were identified and described. The information was obtained by means of primary sources and the data were processed by using descriptive statistics through percentage analysis. The global hospital infection rate did not correspond with the national average; the mortality rate was diminished according to the indicator established; concerning location, the respiratory system was the most affected one, the positive index of the samples was high, the germ that prevailed was the Citrobacter diversus (AU)


Subject(s)
Humans , Cross Infection
11.
Rev Electron ; 38(6)jul. 2013. tab
Article in Spanish | CUMED | ID: cum-54170

ABSTRACT

Se realizó un estudio descriptivo de corte transversal, de utilización de medicamentos de tipo indicación-prescripción con elementos de esquema terapéutico, con el objetivo de evaluar la pertinencia del esquema terapéutico de antimicrobianos, para el tratamiento de las infecciones del tracto urinario en la atención primaria de salud en el municipio Las Tunas, en el período comprendido entre enero a diciembre de 2012. El universo estuvo constituido por el total de pacientes con prescripción médica de antimicrobianos por impresión diagnóstica de sepsi o infección urinaria, la muestra fue de 120 pacientes. Los datos se obtuvieron de fuentes primarias y secundarias, procesados por estadística descriptiva, a través del análisis porcentual. Las infecciones del tracto urinario, baja y alta no complicadas, fueron las que más afectaron a la población. Los antimicrobianos más utilizados: cotrimoxazol, ciprofloxacina y ácido nalidíxico. A la mayoría de los pacientes se les prescribieron terapéuticas antimicrobianas no pertinentes, debido a la selección inadecuada (AU)


A transversal descriptive study on the use of prescription drugs with elements of therapeutic scheme was carried out at primary health care of Las Tunas municipality from January to December, 2011. The study was aimed at assessing the pertinence of the therapeutic scheme of antimicrobials for the treatment of urinary tract infections. The universe was made up by all the patients with medical prescription of antimicrobials due to diagnostic impression of urinary sepsis or infection. The sample included 120 patients. The data was obtained from primary and secondary sources and were processed by descriptive statistics by means of the percentage analysis. The non-complicated lower and upper urinary tract infections were the ones that mostly affected the population. The antimicrobials mostly used were cotrimoxazol, ciprofloxacin and nalidixic acid. Most of the patients were prescribed non-pertinent antimicrobial drugs due to an inadequate selection (AU)


Subject(s)
Humans , Urologic Diseases/therapy
12.
Rev Electron ; 38(3)mar. 2013.
Article in Spanish | CUMED | ID: cum-54139

ABSTRACT

Se realizó una intervención educativa con el objetivo de modificar los conocimientos sobre Tuberculosis Pulmonar en una población del estado Sucre, República Bolivariana de Venezuela, donde se implementa el programa Barrio Adentro. El universo de estudio estuvo constituido por los pacientes con más de un factor de riesgo para adquirir la enfermedad, pertenecientes a Comunidad Independencia, Parroquia Guiria, Municipio Valdez, durante el período comprendido entre enero de 2010 a diciembre del 2011, quedando finalmente constituida la muestra por 90 pacientes. La investigación se desarrolló en tres etapas: diagnóstico, intervención y evaluación. La obtención de la información se basó en una entrevista, donde se recogieron datos que fueron llevados a una planilla de vaciamiento. Para evaluar el conocimiento sobre Tuberculosis se aplicó una encuesta antes y después de desarrollada la intervención propiamente dicha. Con la aplicación de la intervención se logró modificar positivamente los conocimientos acerca de la definición, factores de riesgo, vías de transmisión, manifestaciones clínicas y conducta general ante la Tuberculosis. Se recomienda divulgar y publicar los resultados de la intervención educativa en todo el municipio pues las condiciones higiénicas sanitarias son propicias para el contagio (AU)


An educational intervention with the objective of modifying the knowledge about pulmonary tuberculosis was carried out in some population of Sucre state, República Bolivariana de Venezuela, where Barrio Adentro program is being implemented. The universe of study was made up by the patients who had more than one risk factor for acquiring the sickness and who belonged to Independencia Community, Guiria Parish, Valdés Municipality, from January, 2008 to December, 2010. The sample comprised 90 patients. The investigation was developed in three stages: diagnosis, intervention and evaluation. The collection of data was carried out by means of an interview, and the obtained information was statistically processed and jotted down in a form. The interview was intended to evaluate the knowledge on tuberculosis and it was applied before and after the intervention. By means of the intervention, it was possible to modify positively their knowledge about definition, risk factors, and ways of transmission, as well as the clinical manifestations, and general behavior concerning tuberculosis. It is recommended to publish and broadcast the results of the educational intervention in the whole municipality, since the poor hygienic conditions of this community can potentially increase the risk of dissemination (AU)


Subject(s)
Humans , Tuberculosis, Pulmonary , Risk Factors
13.
Breast Cancer Res Treat ; 134(3): 1199-207, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22460615

ABSTRACT

In recent decades, breast cancer cases have increased steadily worldwide. However, the increases do not hold across all demographics and breast cancer cases in low and middle income countries have increased much faster than the global trend. Colombia is not an exception. Breast cancer was the most frequent tumor and the second cause of cancer-related deaths in women in 2008, with an estimated of 6,700 new cases and 2,100 deaths. We present here an analysis of breast cancer mortality rates and trends in Colombia, over the period 1985-2008. We studied overall and age-specific changes in breast cancer mortality using change-point Poisson regression models. Between 1985 and 2008, there were 32,375 breast cancer deaths in women in Colombia. Breast cancer mortality increased since 1985, although the annual increase varied between age groups and socioeconomic levels. Only in women aged 45-64 years old that live in areas of high socioeconomic levels, breast cancer mortality was stable or decreasing. Hence, successful cancer control is possible in middle income countries, as shown by the progress observed in certain groups. The development of an integrated strategy of early detection and early access to proper treatment, suitable for areas with limited resources, is an urgent necessity.


Subject(s)
Breast Neoplasms/epidemiology , Healthcare Disparities/trends , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Breast Neoplasms/mortality , Colombia/epidemiology , Female , Humans , Middle Aged , Social Class , Young Adult
14.
AIDS Educ Prev ; 21(5 Suppl): 109-23, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19824839

ABSTRACT

This article describes a quasi-experimental evaluation of a community-based, culturally and ecologically tailored HIV prevention intervention for Mexican American female adolescents grounded in the AIDS risk reduction model. A total of 378 Mexican American female adolescents (mean age = 15.2) participated in either the nine-session SHERO's (a female-gendered version of the word hero) intervention or a single session information-only HIV prevention intervention. Assessment data were collected at pretest, posttest, and 2-month follow up. Significant improvements across all time points were revealed on measures of self-esteem, condom attitudes, beliefs regarding a woman's control of her sexuality, beliefs regarding sexual assault, perceived peer norms, and HIV/AIDS and STI knowledge. At posttest SHERO's participants were more likely to carry condoms and to report abstaining from vaginal sex in the previous 2 months; and at 2-month follow up they reported using condoms more often in the preceding 2 months and planned on using them more frequently in the coming 2 months. Findings support the development of community-based adolescent HIV prevention interventions that address culturally specific ecological factors.


Subject(s)
HIV Infections/prevention & control , Health Education/methods , Health Knowledge, Attitudes, Practice , Mexican Americans/statistics & numerical data , Sexual Behavior/ethnology , Adolescent , Adolescent Behavior/psychology , Analysis of Variance , Community Health Services/organization & administration , Female , Follow-Up Studies , HIV Infections/ethnology , Health Promotion/methods , Humans , North Carolina , Poverty , Program Evaluation/methods , Risk Reduction Behavior , Urban Population , Young Adult
15.
Anal Bioanal Chem ; 389(7-8): 2297-302, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17952418

ABSTRACT

A selective method for the determination of L-glutamate in foodstuffs has been developed. It was based on the competition established between the analyte and the dye Coomassie brilliant blue G (CBBG) to interact with the surfactant didodecyldimethylammonium bromide (DDABr). The measurement parameter was the amount of DDABr required to reach a given dye-to-surfactant binding degree. It was obtained by photometric titration on the basis of the changes observed in the spectral characteristics of the dye when CBBG-DDABr aggregates were formed. The calibration graph obtained was linear in the L-glutamate concentration interval 0.2-5 mM (detection limit 0.05 mM). The high selectivity of the proposed method (other amino acids and food additives did not interfere at the concentrations present in foodstuffs) permitted the direct analysis of food samples after dissolution of the analyte in hot water. The accuracy of the surfactant to the dye binding degree method was demonstrated by determining L-glutamate in different kinds of foodstuffs (liquid and dried soups, seasonings, pasta sauces and dried mushroom creams) and comparing the results obtained with those provided by the commercial Boehringer Mannheim essay.


Subject(s)
Food Analysis/methods , Glutamic Acid/analysis , Quaternary Ammonium Compounds/metabolism , Rosaniline Dyes/metabolism , Surface-Active Agents , Calibration , Food Analysis/standards , Glutamic Acid/chemistry , Indicators and Reagents , Quality Control , Quaternary Ammonium Compounds/chemistry , Rosaniline Dyes/chemistry , Surface-Active Agents/chemistry , Surface-Active Agents/metabolism
16.
Anal Chim Acta ; 588(2): 252-60, 2007 Apr 11.
Article in English | MEDLINE | ID: mdl-17386818

ABSTRACT

The surfactant to dye binding degree (SDBD) method is proposed for the routine monitoring of anionic surfactants in aqueous environmental samples and their analytical features compared with those provided by the standard methylene blue (MB) method. This new analytical approach is based on the effect that anionic surfactants exert on the binding degree of the cationic surfactant didodecyldimethylammonium bromide (DDABr) to the anionic dye Coomassie Brilliant Blue G (CBBG). The formation of DDABr-CBBG aggregates is monitored photometrically. The analytical applicability of the proposed method was demonstrated by determining anionic surfactants in tap, river and swamp water, and raw and treated sewage. The mean recoveries obtained ranged between 99 and 101%. The SDBD method offers important advantages over the classical MB method: it is more sensitive, selective, precise, simple and rapid; the analytical response is independent of the molecular structure of the anionic surfactants, and the volume of sample required for analysis and the consumption of organic solvents are significantly reduced.

17.
Analyst ; 131(1): 81-9, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16365667

ABSTRACT

An aggregation parameter-based methodology for determining acid and neutral drugs in pharmaceutical dosage forms is presented. The method is based on competitive self-assembly in ternary dye-surfactant-drug aqueous mixtures. Dyes bearing charge of opposite sign to that of surfactants bind to surfactant to form mixed dye-surfactant aggregates, which are monitored from changes in the spectra features of the dye. The drug competes with the dye to interact with the surfactant to form drug-surfactant aggregates, which results in a decrease in the surfactant to dye binding degree proportional to the drug concentration in the aqueous solution. Coomassie Brilliant Blue G (CBBG) and didodecyldimethylammonium bromide (DDABr) were the dye and surfactant reactant used, respectively. The suitability of the surfactant to dye binding degree (SDBD) method to determine drugs with very different molecular structure: propionic (flurbiprofen, ibuprofen, naproxen and ketoprofen) and acetic (diclofenac, felbinac and zomepirac) acids, indolines (indomethacin and sulindac), glycyrrhetinic acid derivatives (carbenoxolone and enoxolone), salicylates (diflunisal and phenyl salicylate), oxicams (meloxicam, piroxicam and tenoxicam), pyrazolones (phenylbutazone and sulfinpyrazone) and hydrocortisones (dexamethasone and prednisolone) has been proved. The proposed method was successfully applied to the determination of drugs in commercial formulates (effervescent granulates, tablets, suppositories, gels and blisters) with a minimum sample treatment (dilution of liquid samples and dissolution of solid samples).


Subject(s)
Pharmaceutical Preparations/standards , Chemistry, Pharmaceutical , Coloring Agents/chemistry , Dosage Forms , Humans , Hydrogen-Ion Concentration , Pharmaceutical Preparations/analysis , Quality Control , Surface-Active Agents/chemistry
18.
Analyst ; 130(7): 1102-7, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15965536

ABSTRACT

An aggregation parameter-based analytical approach, the surfactant-dye binding degree (SDBD) method, was used, for the first time, to determine aromatic hydrotropic compounds. The anionic dye Coomassie Brilliant Blue G (CBBG) was used as inductor of didodecyldimethylammonium bromide (DDABr) aggregates, whose formation was monitored from changes in the spectral features of the dye. Interactions between hydrotrope and DDABr molecules resulted in a decrease of the degree of binding of the cationic surfactant to CBBG, which was proportional to the concentration of hydrotrope in the aqueous solution. The CBBG-DDABr-hydrotrope chemical system was found to fit to the mathematical expression previously derived for the determination of amphiphilic compounds. The hydrotrope-surfactant bond strength determined the sensitivity achieved for the determination of hydrotropic compounds, which was highly dependent on the molecular structure of the analyte. The high precision (the relative standard deviation for 7 mg l(-1) of salicylic acid was 0.8%), rapidity (measurements were performed in a few minutes) and low cost (in both instrumentation and reactants) of the proposed method, made it especially suitable for quality control. The practical analytical applicability of the SDBD method for the control of hydrotropic drugs in pharmaceutical preparations was demonstrated by quantifying salicylic acid and acetyl salicylic acid in liquid (solutions) and solid (tablets, granulates, unguents, gels and creams) samples, which were directly analyzed after dissolution of the samples.


Subject(s)
Pharmaceutical Preparations/chemistry , Surface-Active Agents/chemistry , Chemistry, Pharmaceutical , Coloring Agents , Rosaniline Dyes , Solubility , Solutions
19.
Rev. argent. cir. plást ; 11(3): 135-141, 2005. ilus
Article in Spanish | BINACIS | ID: bin-122228

ABSTRACT

Las grandes pérdidas de la cobertura cutánea y los fenómenos toxo-inflamatorios que se asocian, ya se trate de quemaduras, necrolisis tóxica epidérmica o porcesos bacterianos productores de toxinas con gran destrucción tisular, configuran una situación clínica crítica con alto riesgo de vida. Con los principios de tratamiento de grandes quemados, el control de la infección local y sistémica, el sostén clínico intensivo en una unidd de máxima complejidad y la adecuada asistencia nutricional y respiratoria se pudo tratar satisfactoriamente una fascitis necrotizante con pérdida de la cobertura cutánea en aproximadamente un 30 por ciento de la SCT causada por una infección de Estreptococo beta hemolítico grupo A en un recién nacido pretérmino (RNPT) de 1287g al nacer.(AU)


Subject(s)
Male , Humans , Infant, Newborn , Fasciitis, Necrotizing/physiopathology , Fasciitis, Necrotizing/therapy , Hyaline Membrane Disease , Shock, Septic
20.
Rev. argent. cir. plást ; 11(3): 135-141, 2005. ilus
Article in Spanish | LILACS | ID: lil-482551

ABSTRACT

Las grandes pérdidas de la cobertura cutánea y los fenómenos toxo-inflamatorios que se asocian, ya se trate de quemaduras, necrolisis tóxica epidérmica o porcesos bacterianos productores de toxinas con gran destrucción tisular, configuran una situación clínica crítica con alto riesgo de vida. Con los principios de tratamiento de grandes quemados, el control de la infección local y sistémica, el sostén clínico intensivo en una unidd de máxima complejidad y la adecuada asistencia nutricional y respiratoria se pudo tratar satisfactoriamente una fascitis necrotizante con pérdida de la cobertura cutánea en aproximadamente un 30 por ciento de la SCT causada por una infección de Estreptococo beta hemolítico grupo A en un recién nacido pretérmino (RNPT) de 1287g al nacer.


Subject(s)
Male , Humans , Infant, Newborn , Fasciitis, Necrotizing , Hyaline Membrane Disease , Shock, Septic
SELECTION OF CITATIONS
SEARCH DETAIL
...