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The purpose of this study was to determine the epidemiology of leptospirosis in rural areas of Ciénaga de Oro, Córdoba, Colombia, a convenience sampling was carried out on 13 farms. The sample size was 325 reproductive age cows, 11 canine samples, and 20 humans. The samples were subjected to MAT analysis with 11 serogroups of Leptospira interrogans sensu lato. Once the MAT results were received, urine samples were collected from 78 cows, along with 39 water samples, for bacteriological cultures and PCR for the 16S rRNA gene in L. interrogans sensu lato. Positive PCR samples were sequenced to determine the possible genome species. The leptospirosis seroprevalence was 74.5% in the cattle, 70.0% in the dogs, and 45.5% in the humans. Although isolation was not achieved, L. interrogans sensu lato was detected by PCR in three urine samples and in a sample of wastewater. The sequencing confirmed the circulation of pathogenic species. The high prevalence of antibodies for L. interrogans sensu lato and the molecular evidence led to the inference that the rural areas of Ciénaga de Oro are endemic and that cattle can act as renal carriers and contaminate water sources, which increases the risk of contracting leptospirosis.
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Enfermedades de los Bovinos/epidemiología , Enfermedades de los Perros/epidemiología , Leptospira interrogans/aislamiento & purificación , Leptospirosis/epidemiología , Leptospirosis/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Colombia/epidemiología , Enfermedades de los Perros/microbiología , Perros , Femenino , Humanos , Leptospira interrogans/clasificación , Leptospira interrogans/genética , Leptospirosis/microbiología , Masculino , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis , Estudios Seroepidemiológicos , SerogrupoRESUMEN
Titanium dioxide (TiO2) thin films have generated considerable interest over recent years, because they are functional materials suitable for a wide range of applications. The efficient use of the outstanding functional properties of these films relies strongly on their basic characteristics, such as structure and morphology, which are affected by deposition parameters. Here, we report on the influence of plasma power and precursor chemistry on the growth kinetics, structure and morphology of TiO2 thin films grown on Si(100) by plasma-enhanced atomic layer deposition (PEALD). For this, remote capacitively coupled 13.56 MHz oxygen plasma was used to act as a co-reactant during the ALD process using two different metal precursors: titanium tetrachloride (TiCl4) and titanium tetraisopropoxide (TTIP). Furthermore, we investigate the effect of direct plasma exposure during the co-reactant pulse on the aforementioned material properties. The extensive characterization of TiO2 films using Rutherford backscattering spectroscopy, ellipsometry, x-ray diffraction (XRD), field-emission scanning electron microscopy, and atomic force microscopy (AFM) have revealed how the investigated process parameters affect their growth per cycle (GPC), crystallization and morphology. The GPC tends to increase with plasma power for both precursors, however, for the TTIP precursor, it starts decreasing when the plasma power is greater than 100 W. From XRD analysis, we found a good correlation between film crystallinity and GPC behavior, mainly for the TTIP process. The AFM images indicated the formation of films with grain size higher than film thickness (grain size/film thickness ratio ≈20) for both precursors, and plasma power analysis allows us to infer that this phenomenon can be directly related to the increase of the flux of energetic oxygen species on the substrate/growing film surface. Finally, the effect of direct plasma exposure on film structure and morphology was evidenced showing that the grid removal causes a drastic reduction in the grain size, particularly for TiO2 synthesized using TiCl4.
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PURPOSE: To determine the consequences of the chronic use of systemic corticosteroids in children with juvenile rheumatoid arthritis by means of evaluating osteochondral effects depicted by magnetic resonance imaging. PATIENTS AND METHODS: We reviewed clinical and magnetic resonance imaging findings in 69 children (72 knees) with juvenile rheumatoid arthritis. Two groups were studied. Group I: 34 (49.3%) children had previous or current use of systemic corticotherapy (22 girls; 12 boys; mean age: 11.3 years; mean disease duration: 5.9 years; mean corticotherapy duration: 2.9 years; mean cumulative dose of previous corticosteroids: 5000 mg); Group II: 35 (50.7%) children had no previous use of corticosteroids (27 girls; 8 boys; mean age: 11.7 years; mean disease duration: 5.3 years). The groups were compared statistically. RESULTS: In the group that had received corticotherapy (Group I), osteochondral abnormalities were significantly correlated to long-standing disease (>3.5 years; p<0.001). This correlation was not found in the group that had no previous history of corticotherapy (Group II). No correlations were established between median dose of corticosteroids and magnetic resonance imaging findings. CONCLUSION: It is important to further investigate the long-term intra-articular effects of systemic corticotherapy to ensure that the side effects of the aggressive therapy will not be more harmful for the joints than the symptoms suffered over the natural course of the disease.
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Corticoesteroides/uso terapéutico , Artritis Juvenil/tratamiento farmacológico , Enfermedades Óseas/diagnóstico , Rodilla , Adolescente , Corticoesteroides/efectos adversos , Adulto , Enfermedades Óseas/inducido químicamente , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Factores de TiempoRESUMEN
BACKGROUND: Contrast-enhanced color Doppler ultrasonography is a non-radiation-bearing tool that can be of value for assessment of inflammatory and vascular synovial changes in juvenile rheumatoid arthritis (JRA). OBJECTIVES: To evaluate the effect of contrast-enhanced color Doppler ultrasound (US) in the evaluation of synovial changes in the knees of children with JRA. MATERIALS AND METHODS: Sagittal color Doppler sonograms of 31 knees in 22 patients with JRA and of 10 knees in 5 control subjects were obtained before (at baseline) and after (at peak contrast phase) intravenous injection of SHU 508. Images were assessed for overall mean pixel intensity within the synovial tissue and for peak enhancement ratios [[(mean pixel intensity values at maximum contrast enhancement-unenhanced mean pixel intensity values)/unenhanced mean pixel intensity values] x 100]. The joints were classified into three groups by clinical/laboratory criteria: group A (active disease in the knee), n = 9; group B (quiescent disease with serum chemistry levels of active disease), n = 12 and group C (remission disease), n = 10. RESULTS: Mean color pixel intensity values were markedly increased by the use of US contrast agents in groups A (P = 0.004) and B (P = 0.0001), did not reach statistical significance in group C (P = 0.06) and remained essentially unchanged in the control group (P = 0.25). Enhancement ratios for the three groups of JRA patients were not different (P = 0.38) (mean +/- SD, 720% +/- 402 for group A, 731% +/- 703 for group B and 314% +/- 263 for group C). CONCLUSION: Contrast-enhanced color Doppler imaging holds promise for the detection of active synovial inflammatory disease in subclinical cases of JRA, thereby allowing earlier treatment and improved clinical outcome.