Validación del Analyz-Strep A Rapid Test en el diagnóstico de la faringitis aguda / Validation Analyz-Strep A Rapid Test in the diagnosis of acute pharyngitis

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Calcium modulates interactions between bacteria and hydroxyapatite.

Bacterial adhesion onto hydroxyapatite is known to depend on the surface properties of both the biomaterial and the bacterial strain, but less is known about the influence of the composition of the aqueous medium. Here, the adhesion of Streptococcus mutans and 3 different Lactobacilli on powdered hydroxyapatite was shown to change with Ca2+ concentration. The effect depends on the surface properties of each strain. Adhesion of Lactobacillus fermentum and salivarius (and of Streptococcus mutans at low Ca2+) was enhanced with increasing Ca2+ concentration. Lactobacillus casei was efficiently removed by adhesion on hydroxyapatite, even without Ca2+ addition, and the effect of this ion was only marginal. The results are interpreted in terms of Ca2+-mediated adhesion, and relative to the hydrophobic properties of each strain and the electrical properties of the bacterial and solid surfaces (electrophoretic mobility).

Surface properties of various powdered hydroxyapatites.

Electrophoretic mobilities of various synthetic and semisynthetic hydroxyapatites (Ca10(PO4)6(OH)2, HAP) suspended in aqueous solutions have been measured as a function of pH and calcium concentration. The studied powders differ in particle size, crystallinity degree and surface contamination (carbonate). When equilibrated in mineral acids or bases, a large plateau of negative mobility is observed in the pH range 5-8, with increasing negative values at higher pH. Only in the case of the sample composed of nanoparticles, positive mobility obtains at pH < 8.9. When Ca2+ is added, positive mobility values are observed for all samples, and a bell-shaped profile results as a function of pH. Two possible models are explored to describe the results: the Nernstian approach, which assumes solubility equilibrium and surface potentials determined by the three potential-determining ions (Ca2+, PO3-4, and OH-), and the surface complexation approach, based on the idea of negligible phase transfer of structural phosphate. The Nernstian model is inadequate, whereas a very simple surface complexation model based on the equations Ca5(PO4)+3 = Ca4(PO4)-3 + Ca2+,Ca4(PO4)-3 + H+ = Ca4(PO4)2(PO4H),Ca5(PO4)+3 + OH- = Ca5(PO4)3(OH),coupled with a very simple electrical double layer, model suffices to reproduce the bell-shaped profile of the mobility as a function of pH in the presence of added calcium salts. The results also show that the sample composed of nanoparticles exchanges ions more easily with the solution, without reaching the solubility equilibrium in the explored timespans. In the presence of soluble phosphate salts, it is postulated that the same surface ensembles define the surface charge, with participation of phosphate as described by the equation Ca5(PO4)+3 + PO3-4 = Ca4(PO4)-3.HAP is just one member of a family of calcium phosphates with different (Ca)/(P) ratios. Electrophoretic mobilities of another member, tricalcium diphosphate, Ca3(PO4)2, were also measured and shown to be described by the same basic model. Comparison with previous literature data shows that the negative plateau in the mobility is a general feature of many HAP samples at low Ca2+, again in agreement with the surface complexation model. FTIR data demonstrates that surface phosphate indeed undergoes protonation, as postulated in the model.

[Design and validation of a questionnaire for the detection of major depression in elderly patients]. / Diseño y validación de un cuestionario para la detección de depresión mayor en pacientes ancianos.

BACKGROUND AND OBJECTIVE: The aim of this study was to design and validate a scale to detect major depressive disorders in elderly individuals in primary care (Detection of Depression in the Elderly Scale [DDES]). METHODS: We performed an observational and cross-sectional study for the validation of a scale, administered by means of a personal interview, in 259 patients aged 65 years old or older. Available instruments were reviewed and the questions were designed. Subsequently, a first pilot study was performed. In a second pilot study the reproducibility of the instrument was analyzed. The gold standard was the result of a standardized psychiatric interview performed by psychiatrists (DSM-IV criteria and SCAN interviews). RESULTS: The intraclass correlation coefficients corresponding to the test-retest and inter-rater reliability were 0.858 (95% confidence interval [CI], 0.634-0.946) and 0.908 (95% CI, 0.726-0.969) respectively. Two hundred sixteen subjects underwent an assessment, in which primary care and psychiatric evaluations were blinded. Major depression was diagnosed in 81 patients (37.5%; 95% CI, 31.1-44.4). The internal consistency of the DDES was good (Cronbach's alpha = 0.79). Exploratory factorial analysis revealed an 8-component structure (55.8% of explained variance). A cutoff score of 15 or more for the DDES showed sensitivity of 90.1% (95% CI, 80.95-95.33), specificity of 74.8% (95% CI, 66.48-81.71) and a likelihood ratio (+) of 3.58 (95% CI, 2.65-4.83). CONCLUSIONS: The DDES is a clinically useful instrument for the detection of major depression in elderly patients in primary care.

Diseño y validación de un cuestionario para la detección de depresión mayor en pacientes ancianos / Design and validation of a questionnaire for the detection of major depression in elderly patients

Fundamento y objetivo: Elaborar y validar una escala para detectar trastornos depresivos mayores (TDM) en ancianos que utilizan las consultas de atención primaria (Escala para la Detección de Depresión en Ancianos [EDDA]). Métodos: Estudio observacional transversal para validar una escala, administrada mediante entrevista personal, en 259 pacientes de 65 o más años. Tras revisar los instrumentos disponibles y elaborar los ítems, se realizó una primera prueba piloto o pretest. En una segunda prueba piloto se analizó la reproducibilidad del instrumento. El estándar de oro fue el resultado de una entrevista psiquiátrica estandarizada realizada por psiquiatras (criterios DSM-IV y entrevista SCAN). Resultados: Los coeficientes de correlación intraclase (CCI) correspondientes a la fiabilidad intra e interobservador fueron, respectivamente, de 0,858 (intervalo de confianza [IC] del 95%, 0,634-0,946) y 0,908 (IC del 95%, 0,726-0,969). El número de sujetos válidos para el estudio fue de 216 ancianos, en quienes se realizó, de forma ciega, una valoración en consultas de atención primaria y de psiquiatría. En éstas se objetivó la existencia de un TDM en 81 de ellos (37,5%; IC del 95%, 31,1-44,4). La EDDA mostró una elevada coherencia interna (* de Cronbach = 0,79). El análisis factorial determinó que existían 8 factores capaces de explicar el 55,8% de la varianza total. Para una puntuación mayor o igual a 15, la EDDA presenta una sensibilidad del 90,1% (IC del 95%, 80,95-95,33), una especificidad del 74,8% (IC del 95%, 66,48-81,71) y un cociente de probabilidad positivo de 3,58 (IC del 95%, 2,65-4,83). Conclusiones: La EDDA es un instrumento clínicamente útil para la detectar los TDM de los ancianos en la atención primaria

Background and objective: The aim of this study was to design and validate a scale to detect major depressive disorders in elderly individuals in primary care (Detection of Depression in the Elderly Scale [DDES]). Methods: We performed an observational and cross-sectional study for the validation of a scale, administered by means of a personal interview, in 259 patients aged 65 years old or older. Available instruments were reviewed and the questions were designed. Subsequently, a first pilot study was performed. In a second pilot study the reproducibility of the instrument was analyzed. The gold standard was the result of a standardized psychiatric interview performed by psychiatrists (DSM-IV criteria and SCAN interviews). Results: The intraclass correlation coefficients corresponding to the test-retest and inter-rater reliability were 0.858 (95% confidence interval [CI], 0.634-0.946) and 0.908 (95% CI, 0.726-0.969) respectively. Two hundred sixteen subjects underwent an assessment, in which primary care and psychiatric evaluations were blinded. Major depression was diagnosed in 81 patients (37.5%; 95% CI, 31.1-44.4). The internal consistency of the DDES was good (Cronbach's alpha = 0.79). Exploratory factorial analysis revealed an 8-component structure (55.8% of explained variance). A cutoff score of 15 or more for the DDES showed sensitivity of 90.1% (95% CI, 80.95-95.33), specificity of 74.8% (95% CI, 66.48-81.71) and a likelihood ratio (+) of 3.58 (95% CI, 2.65-4.83). Conclusions: The DDES is a clinically useful instrument for the detection of major depression in elderly patients in primary care

[Detection of bulimia nervosa in primary health care consultations]. / Detección de bulimia nerviosa en las consultas de Atención Primaria.

INTRODUCTION: To estimate the prevalence of bulimia nervosa and bulimic behavior in women who come to Primary Health Care consultations, using the DSM-IV criteria. DESIGN: Descriptive, observational study Setting. Primary Health Care. PARTICIPANTS: Women over 14 years who come to general medicine consultations. Selection by systematic sampling of 175 women (proportion expected: 4%; confidence index: 95%; accuracy: 3%). MAIN MEASURES: Examination, by semi-structured interview, of diagnostic criteria of bulimia (recurrent binge eating, compensatory behaviors and excessive concern about weight or body image), socio-demographic variables and variables on morbidity (health problems according to CIPSAP-2-defined). RESULTS: Prevalence of bulimia was 5.3% (95% CI: 2.4-9.7), there being recurrent binge-eating in 23.4%. Among the compensatory behaviors, fasting (13.5%), intense exercise (8.2%) and self-induced vomiting (4.7%) were the most frequent. In women with bulimia, a background of anorexia and establishment of goals to lose weight appeared more frequently (p <0.05). Their average age was significantly lower (p <0.05) (31.2 14.7 SD). By logistic regression, the associated variables with the presence of bulimia were age (OR: 0.94), existence of previous psychiatric morbidity (OR: 9.0) and having previously set goals to lose weight (OR:7.3). CONCLUSIONS: In the women who came to the Primary Health Care consultations, prevalence of bulimia is greater than that described in the general female population. This disorder is more frequent in younger women and in those who present a background of psychiatric morbidity. Examination of the diagnostic criteria makes its detection easy in Primary Health Care consultations.

[Leukocytoclastic vasculitis due to hypersensitivity to microfilariae]. / Vasculitis leucocitoclástica por hipersensibilidad a microfilarias.

A case of a Caucasian girl with leukocytoclastic vasculitis, polyarthritis and eosinophilia is presented. A blood test showed microfilariasis, probably of the Loa Loa type. The epidemiology, clinical features, diagnosis and treatment of filariasis is described. In the western literature revised, reactive arthritis has been described but none of the other clinical features of our case. The presence of circulating immune complex might explain the pathogenic mechanism. We believe that filariae should be included amongst the causes of hypersensitivity vasculitis and in the differential diagnosis of eosinophilic vasculitis.

Acidity constants of benzidine in aqueous solutions.

The acidity constants of benzidine (Bz) in aqueous solutions determined potentiometrically at 25 degrees were K(a1) = (1.11 +/- 0.08) x 10(-5), K(a2) = (1.45 +/- 0.12) x 10(-4). The apparent mixed constants in 0.1M sodium nitrate are K(a1) = (5.37 +/- 0.28) x 10(-6) and K(a2) = (1.14 +/- 0.09) x 10(-4). The ultraviolet spectra were recorded as a function of pH and analysed with these constants to obtain the absorption spectra of H(2)Bz(2+), HBz(+) and Bz; the corresponding wavelengths of maximal absorption are 247, 273 and 278 nm, and molar absorptivities 1.63 x 10(4), 1.76 x 10(4) and 2.26 x 10(4) 1.mole(-1).cm(-1).

Normalization of the blunted ventilatory response to acute hypoxia in congenital cyanotic heart disease.

Patients with congenital cyanotic heart disease have a blunted ventilatory response to hypoxia, but the permanence of the blunting is disputed. To determine how early the blunted ventilatory response develops and whether it is reversible, we studied three groups of children and young adults: five (seven to 13 years of age) with acyanotic heart disease, eight (seven to 16) with cyanotic congenital heart disease (arterial oxygen saturation, 55 to 83 per cent), and 13 (seven to 17) whose cardiac defects were repaired (arterial oxygen saturation, 93 to 98 per cent). The ventilatory response to acute hypoxia was subnormal in the hypoxemic children in that their ventilation showed little increase when arterial oxygen saturation fell by 10 to 20 per cent, compared to a 150 to 300 per cent increase in the control subjects. This characteristic even appeared in a seven-year-old patient, indicating that the disorder occurs in early life. The appearance of blunted ventilatory response is delayed when hypoxia from birth is less severe. After operation, with return of the arterial hypoxemia to normal, the response was in the normal range. We conclude that the blunted response is reversible.

Antibiotics from Pseudomonas reptilivora. I. Taxonomic classification and optimal conditions of fermentation for antibiotic production.

A bacterium able to produce wide-spectrum antibiotic substances was isolated from a plant extract. The antibiotic-producing bacterium was identified as Pseudomonas reptilivora after suitable morphological and biochemical assays. Optimal yield conditions for antibiotic production in liquid medium have been established.

Cholinergic mechanisms on the heart and coronary circulation.

1. The effects of rapid intracoronary injection of acetylcholine (ACh) were studied in anaesthetized open chest dogs. Changes in phasic coronary blood flow were followed with non-cannulating electromagnetic flow probes and in contractile force with isometric strain gauges.2. Increasing doses of ACh from 0.01 to 100 mug produced progressively larger increases in systolic and diastolic coronary blood flow and progressive decreases in end-diastolic vascular resistance which were blocked by atropine but not by propranolol.3. Contractile force showed both negative and positive responses. The negative inotropic effect was small and was blocked by atropine but not by propranolol. The threshold for the negative inotropic response was higher than for the coronary vasodilator effect and the dose response curve was flatter. The positive inotropic response usually showed two components. One component reached its maximum 13 to 18 s after injection, had a high threshold (over 1 mug), was potentiated by atropine and blocked by propranolol. The other reached its maximum 25 to 60 s after the injection, had a threshold between 0.01 and 0.1 mug, and was blocked by atropine but not by propranolol.4. These results suggest that the coronary dilator response, the negative inotropic response and part of the positive inotropic response are mediated through "muscarinic" receptors. The remaining component of the positive inotropic response appears to involve catecholamine release.