T cell suppression in vitro during Toxoplasma gondii infection is the result of IL-2 competition between Tregs and T cells leading to death of proliferating T cells.

A reduced proliferation to T cell mitogens is observed in vitro in murine cells isolated during the acute phase of Toxoplasma gondii infection. Foxp3(+) regulatory T cells (Tregs) mediate this suppression, which is interleukin (IL)-2 dependent. In this work, we analysed the mechanism of this Treg-mediated suppression. We found that removal of antigen-presenting cells (APC) from spleen cells from infected mice did not modify suppression but further elimination of Tregs led to a restored proliferation, demonstrating that Tregs mediate suppression in the absence of APC. Production of IL-2 by T cells from infected animals was abolished but partially restored when Tregs were removed. However, IL-2 levels and T cell proliferation were restored when Tregs and T cells were separated by transwells, indicating that Tregs require close proximity with T cells to induce suppression. Tregs from infected mice were able to reduce proliferation of CTLL-2 cells in the classical IL-2 bioassay, strongly suggesting that Tregs compete with T cells for IL-2. We found that T cells from infected mice died after a few rounds of division in vitro, but addition of recombinant IL-2 or removal of Tregs abolished this effect. Our results showed that suppression of T cell proliferation during acute Toxoplasma gondii infection is the result of death of proliferating T cells by Treg-mediated IL-2 competition. Thus, immunosuppression is due to death of proliferating T cells as a consequence of low IL-2 availability.

Phase stabilization and optical response in the ultraviolet range, due to terbium concentration in hafnium oxide nanoparticles.

This work reports the influence of terbium trivalent ions on growing kinetics and the phase in hafnium oxide nanoparticles, as well as response to radiation in the range from 256 to 286. The nanoparticles were obtained by the hydrothermal route maintaining the temperature constant and varying the reaction time and the terbium concentration. The results show a gradual change in the phase with the concentration of terbium trivalent ions, going from the monoclinic phase, present at low concentrations, to the tetragonal phase, which appears from dopant concentrations greater than 5% at., increasing in amount with concentration of dopant. These phases appear as two perfectly defined morphologies. Furthermore, there is a significant change in radiative lifetimes when the tetragonal phase appears.

Thermally coupled energy levels of Eu 3+ within the BaHfO3 matrix, excited with UV radiation.

The present work reports the study of the thermally coupled energy levels of the trivalent europium ion in the barium hafnate matrix, in the temperature range of 289.7-323.8 K, through the application of ultraviolet radiation. Barium hafnate doped with 1, 3, and 5 atomic % trivalent europium ion was synthesized by the hydrothermal route, using chlorides as precursor elements. X-ray diffraction analysis indicates that the material crystallized in the perovskite cubic phase of barium hafnate, according to diffraction card file number #24-0102. Using high-resolution transmission electron microscopy, it was observed that the obtained crystals have an average size of 10 nm. From the photoluminescent analysis at room temperature, it was found that the sample doped with 3.0% atomic of trivalent europium displayed with the highest luminescent emission, while the photoluminescent analysis as a function of temperature showed that the bands associated with the 5D0 → 7FJ (J = 1,2,3,4) transitions have a strong dependence on temperature in the physical range.

Luminescent behavior of Eu3+ doped BaHfO3 perovskite ceramic under UV radiation.

In this paper, luminescent properties of Europium trivalent ion in the matrix with unbalanced charge of barium hafnate under UV radiation, with special emphasis on the 5D0 → 7F0 transition are reported. The synthesis was conducted by the hydrothermal route at 200 °C with a reaction time of 90 min using chlorides as raw materials. In order to determinate the luminescent quenching concentration, the samples were doped with different amounts of Europium trivalent ions being the sample doped with 1 and 3% at of Eu3+ which shows the highest luminescent emission. X-ray diffraction analysis showed that the material crystallize in the cubic perovskite structure with space group Pm-3m. The Energy Dispersive Spectroscopy (EDS) shows there are not elements other those that Ba, Hf, O and Eu in the synthesized material. Photoluminescent emission spectra show peaks of emission associated with the 5D0 → 7FJ (J = 0,1,2,3,4) transitions, characteristics of europium ion. The 5D0 → 7F0 transition centered at 580 nm showed an unusual great intensity when it was excited with the wavelength associated with the charge transfer band (272 nm). Finally the decay time was measured in the 5D0 → 7FJ (J = 0,1,2,3,4) transitions using the sample doped with Eu3+ (3% at).

A comparative study of some combined treatment regimens in acute toxoplasmosis in mice.

The effectiveness of five treatment regimens was compared to mice during acute and late infection with Toxoplasma gondii. Parasitic cure rates, as judged by failure of brain tissue from surviving mice to produce infection when inoculated into clean mice, were as follows: pyrimethamine + sulfamethoxypyridazine, 92%; clindamycin + sulfamethoxypyridazine, 75%; spiramycin + sulfamethoxypyridazine, 16.7%; trimethoprim + sulfamethoxypryridazine alone, 0%. Pyrimethamine + sulfamethoxypyridazine was the most effective combination against acute toxoplasmosis in mice.

Photo-, cathodo- and thermoluminescent properties of dysprosium-doped HfO2 films deposited by ultrasonic spray pyrolysis.

In this work, the photoluminescent (PL), cathodoluminescent (CL) and thermoluminescent (TL) properties of hafnium oxide films doped with trivalent dysprosium ions are reported. The films were deposited on glass substrates at temperatures ranging from 300 to 600°C, using chlorides as precursor reagents. The surface morphology of films showed a veins shaped microstructure at low deposition temperatures, while at higher temperatures the formation of spherical particles was observed on the surface. X-ray diffraction showed the presence of HfO2 monoclinic phase in the films deposited at temperatures greater than 400°C. The PL and CL spectra of the doped films showed the highest emission band centered at 575nm corresponding to the transitions (4)F9/2→(6)H13/2, which is a characteristic transition of Dy(3+) ion. The greatest emission intensities were observed in samples doped with 1 atomic percent (at%) of DyCl3 in the precursor solution. Regarding the TL behavior, the glow curve of HfO2:Dy(+3) films exhibited spectrum with one broad band centered at about 150°C. The highest intensity TL response was observed on the films deposited at 500°C.

Analysis of temperature on the surface of the wrist due to repetitive movements using sensory thermography.

UNLABELLED: This study examines changes in body temperature generated in the wrist area through sensory thermography technique because of highly repetitive movements, proving with this technique that there is a decreased ability to perform muscular work, and thereby assess possible pathologies of Cumulative Trauma Disorders (CTDs). METHODS: Two healthy right-handed individuals, who performed repetitive work, emulating an operation of the textile industry for three days, generated DTA in the area of the wrist. The evaluation time was of 3 hours 30 minutes in a controlled temperature between 20 and 25°C, 20 minutes stabilization time at the beginning and end of the operation. RESULTS: The maximum temperatures reached were on the right wrist (RW) of 35. 078°C over a period of 1 hour 41 minutes 52 seconds; and on the left wrist (LR), 34.663°C over a period of 2 hours 42 minutes 51 seconds, detected discomfort in their right shoulder and wrist in the time range which identified the highest temperatures. It was shown that the data does not fit a normal distribution for RW and LW; the data fit the three- parameters Weibull distribution for WR and LW with a correlation coefficient between 0.93 to 0.99.

Effect of three coccidiostatics against toxoplasmosis in mice.

Duocoxin, nicrazine and amprol plus showed no therapeutic effect in 50 mice each of which was infected with 25,000 organisms of a virulent Toxoplasma strain.

Alteración de la calidad de vida en 785 pacientes con rinitis alergica / Imaired quality of life in 785 patients with allergic rhinitis

La incorporación del concepto "Calidad de Vida" ha generado entre los médicos y el personal relacionado con la salud, un cambio de actitud en el cual el único objetivo es el beneficio del paciente. "La calidad de vida relacionada con la salud evalúa no sólo las alteraciones producias por la enfermedad, sino el modo en que el paciente las percibe y los efectos beneficioso o no del tratamiento. Objetivo: describir la frecuencia de las alteraciones de la calidad de vida en pacientes con rinitis.

The object to study was to evaluate quality of life in patients with rhinitis.

Angiogénesis inducida por colágena polivinilpirrolidona y heparina en el músculo isquémico / Angiogenesis induced by polivinilpirrolidone collagen and heparin in the ischemic muscle

Estudio de investigación experimental, prospectivo y comparativo, con el objeto de evaluar los efectos de la aplicación exógena de colágena tipo I, Polivinilpirrolidona (PVP) y heparina, en túneles musculares fibrocolágenos, en la extremidad isquémica de la rata, para inducir neovascularización o angiogénesis. Se usó un modelo de isquemia en la extremidad posterior derecha de 40 ratas Wistar en dos tiempos. 1º Ligadura de la arteria iliaca común vía abdominal y colocación de una protesis de silasticpoliéster en el músculo gracilis para la generación de un túnel fibrocolágeno. 2º Ocho semanas después, exposición del paquete vascular femoral, ligadura de esta arteria, localización y extracción de la prótesis, perforación y lavado del túnel fibrocolágeno y aplicación de sustancias. En el grupo I se aplicó solución fisiológica, en el grupo II colágena tipo I con PVP, en el grupo III heparina sódica y grupo IV colágena tipo I con (PVP) y heparina sódica. Para la valoración se llevó a cabo angiografía de las extremidades tratadas, cuantificando el número de intersecciones en una superficie milimétrica de 50 x 50 mm. El mayor número de intersecciones se obtuvo en el grupo IV con una medida de 20.22 contra una media de 13.5 intersecciones en el grupo I (control con sol. fisiológica) = p de 0.14 mediante el análisis de varianza para comparar dos grupos (ANOVA). El estudio demuestra mayor angiogénesis en el músculo isquemico de la rata, si se aplica colágena tipo I con (PVP) y heparina