Cut-off points for isometric handgrip and low limb explosive strength in relation to indicators of overweight/obesity in people with intellectual disabilities: analysis by age groups.

BACKGROUND: The prevalence of overweight/obesity has been increasing globally and in people with Intellectual Disabilities (IDs), this problem is exacerbated even more, which added to a low physical condition that contributes to the deterioration of functionality and increases the risk of developing chronic diseases in the course of life. Therefore, the aim of this study was to establish cut-off points for levels of isometric handgrip and low limb explosive strength in children, adolescents and adults, which identify overweight/obesity in people with IDs and their respective associations. METHODS: The sample was made up of 131 individuals with IDs, belonging to four special and community educational centres in the city of Santiago, Chile. Body mass index (BMI) and waist-to-height ratio (WHR) were used as indicators of overweight/obesity. Handgrip strength was used as a measure of isometric strength, and countermovement jump was used as a measure of low limb explosive strength. For the comparison of variables by age group, the analysis of Ancova, Kruskal-Wallis and chi-square tests were used. The total area under the receiver operating characteristic curve of isometric handgrip and low limb explosive strength was identified as an indicator of overweight/obesity according to age groups. A logistic regression model was used to quantify the effect that strength categories below the cut-off point have on the risk of overweight and obesity. RESULTS: Significant differences were observed between the age groups for body weight, height, BMI and WHR, as well as in the levels of absolute handgrip strength and vertical jump with countermovement (P ≤ 0.05). Children showed the lowest cut-off points for absolute and relative strength. The adolescent group showed the highest cut-off points for relative strength and countermovement jump and adults showed the highest value for absolute strength as indicators of overweight/obesity. Different associations between cut-off points with BMI and WHR were found. CONCLUSIONS: Adolescents showed the highest cut-off point for relative strength and countermovement jump, and adults showed the highest value for absolute strength, according to overweight/obesity indicators (BMI and WHR). It is suggested to adjust resistance training programmes according to age categories for the prevention of overweight/obesity in people with IDs.

Characterization of a novel subset of CD8(+) T cells that expands in patients receiving interleukin-12.

IL-12 has significant antitumor activity in mice that may be mediated by CD8(+) T cells. We show in this report that repeated subcutaneous injections of IL-12 in patients with cancer resulted in the selective expansion of a subset of peripheral blood CD8(+) T cells. This T cell subset expressed high levels of CD18 and upregulated IL-12 receptor expression after IL-12 treatment in vivo. In normal subjects, these CD3(+)CD8(+)CD18(bright) T cells expressed IL-12 and IL-2 receptors and adhesion/costimulatory molecules to a greater degree than other CD8(+) and CD4(+) T cells. They appeared morphologically as large granular lymphocytes, although they did not express NK cell markers such as CD56. In addition, CD8(+)CD18(bright) T cells were almost exclusively T cell receptor (TCR) alphabeta+, and exhibited a TCR Vbeta repertoire that was strikingly oligoclonal, whereas the Vbeta repertoire of CD18(dim) T cells was polyclonal. Although CD8+CD18(bright) T cells demonstrated little functional responsiveness to IL-12 or IL-2 alone in vitro, they responded to the combination of IL-12+IL-2 with strong IFN-gamma production and proliferation and enhanced non-MHC-restricted cytolytic activity. In contrast, CD18(dim) T cells were not activated by IL-12 or IL-2, alone or in combination. These findings demonstrate that CD8+CD18(bright) T cells are a unique population of peripheral blood lymphocytes with features of both memory and effector cells that are capable of TCR-independent activation through combined stimulation with IL-12+IL-2. As this activation results in IFN-gamma production and enhanced cytolytic activity, these T cells may play a role in innate as well as acquired immunity to tumors and infectious pathogens. Additional studies will be necessary to determine whether CD8+CD18(bright) T cells mediate the antitumor effect of IL-12 or IL-2 administered to cancer patients, and if so, whether maximal activation of these T cells with the combination of IL-12+IL-2 in vivo can augment the clinical effectiveness of these cytokines.

Expansion and manipulation of natural killer cells in patients with metastatic cancer by low-dose continuous infusion and intermittent bolus administration of interleukin 2.

Interleukin 2 (IL-2) administered at low doses for prolonged periods can markedly expand the number of CD56(+) natural killer (NK) cells in patients with metastatic cancer. The cytotoxic capacity of NK cells obtained from patients receiving IL-2 in vivo can be dramatically augmented by additional exposure to IL-2 in vitro. These observations formed the basis of a clinical trial in which patients with metastatic cancer were treated with low-dose continuous daily infusions of IL-2 to increase the number of their NK cells in conjunction with intermittent boluses of additional IL-2 to stimulate this expanded pool of cytotoxic cells. Twenty-three patients were registered to receive IL-2 at 4.5 x 10(5) units/m2/day for 8 weeks by continuous i.v. infusion. After 4 weeks of "priming" with low-dose continuous infusion IL-2, cohorts of three to five patients received 5 weekly 2-h boluses of IL-2 at doses ranging from 2.5 x 10(5) units/m2 to 1.0 x 10(6) units/m2. Low-dose continuous infusion IL-2 was usually well tolerated; 2-h bolus infusions of IL-2 were often associated with high fevers and constitutional symptoms that resolved after several hours. Low-dose continuous infusion IL-2 resulted in the progressive expansion of circulating CD56(+)CD3(-) NK cells. In contrast, each bolus infusion of IL-2 resulted in an immediate dramatic decrease in both the number of NK cells and activated T lymphocytes with recovery noted within 24 h. Bolus doses of IL-2 as low as 2.5 x 10(5) units/m2 were capable of producing these effects. Cytolytic activity against NK-sensitive and -resistant targets correlated with the presence of circulating activated NK cells. Our results demonstrate that NK cells expanded by low-dose continuous infusions of IL-2 can be further activated in vivo by exposure to very low doses of IL-2 as a 2-h i.v. bolus. This capacity to manipulate human NK cells in vivo through varying the dose and schedule of IL-2 administration may help in defining the therapeutic potential of these cytotoxic effectors in the treatment of both neoplastic and infectious diseases.

Alterations in Ca2+ signal transduction in critically ill surgical patients.

BACKGROUND: Despite improvements in supportive care and pharmacologic therapies, sepsis and related disorders such as systemic inflammatory response syndrome (SIRS) continue to be a leading cause of death in the intensive care unit. We hypothesized that immune dysfunction in this setting may in part be mediated at the level of early signal transduction in monocytes and neutrophils as manifested by changes in intracellular free Ca2+. METHODS: Monocytes and neutrophils were isolated from patients in the intensive care unit who met the criteria for SIRS and from normal volunteers. Cells were loaded with the Ca(2+)-sensitive fluorescent dye Indo-1 and stimulated with the chemotactic peptide f-Met-Leu-Phe (fMLP). Changes in intracellular calcium ion concentration were measured by flow cytometry. RESULTS: Patient monocytes exhibited a decreased Ca2+ flux (43% +/- 3.1%) as compared with normal monocytes (63% +/- 2.5%) (p < 0.05). Patient neutrophils also exhibited a decreased Ca2+ flux in response to fMLP of 58% +/- 3.7% versus 69.3% +/- 3.1% for normal neutrophils (p < 0.05). Incubation of patient cells in normal plasma reversed this dysfunction and showed an improved Ca2+ flux to 60% +/- 2.7% for monocytes and 71% +/- 3.7% for neutrophils (p < 0.05). Conversely, calcium flux was decreased in both normal monocytes (42.3% +/- 3.1%) and normal neutrophils (55.4% +/- 3.8%) after incubation in SIRS patient plasma (p < 0.05). Incubation of normal monocytes and neutrophils in interleukin-1, interleukin-2, interleukin-6, tumor necrosis factor, or lipopolysaccharide did not show a statistically significant alteration in calcium flux in response to fMLP. CONCLUSIONS: Patients with SIRS exhibit alterations in early signal transduction after stimulation with fMLP in monocytes and neutrophils. This effect appears to be mediated by a soluble factor because the defect in SIRS patient cells can be reversed by incubation in normal plasma and normal cells appear to acquire this defect after incubation in patient plasma. Further studies are underway to identify the factor or factors responsible for this functional defect.

Costimulation of human natural killer cell proliferation: role of accessory cytokines and cell contact-dependent signals.

Despite the importance of natural killer (NK) cells in the immune response, the regulation of human NK cell growth has not been well characterized. We have hypothesized that, similar to the proliferation of T and B lymphocytes, optimal proliferation of NK cells requires costimulatory signals as well as a primary mitogenic stimulus. Evidence for costimulation by both soluble cytokines and cell contact-dependent factors is presented. Soluble IL-1 and TNF were found to augment NK cell proliferation in response to primary mitogenic cytokines, including IL-2, IL-4, IL-7, and IL-12. The costimulatory effect of IL-1 and TNF is strongly enhanced by the calcium ionophore ionomycin. Coculture of NK cells with irradiated K562 cells can largely substitute for the costimulatory signal provided by ionomycin. Costimulation by K562 requires intimate cell contact and is not reconstituted by cell-free supernatants. Activated T lymphocytes can also mediate contact-dependent costimulation of NK cells; resting PBMC, several NK-sensitive cell lines, and all NK-resistant cell lines tested were not found to be costimulatory. Engagement of CD16 did not augment NK cell proliferation. Thus, triggering of natural killing or antibody-dependent cell-mediated cytotoxicity (ADCC) does not consistently provide a costimulatory signal for NK cell proliferation. Cell contact-dependent costimulation of NK cells does not appear to involve known receptors that can costimulate T cells, including CD2, CD27, CD28, CD29, or LFA-1. The molecular nature of the putative NK cell costimulatory receptor remains to be elucidated. Nevertheless, human NK cells could be expanded in vitro using leukocyte-conditioned medium (LCM) as a source of IL-2 and accessory cytokines and ionomycin to bypass the putative receptor for cell contact-dependent costimulation. NK cells expanded in LCM and ionomycin express typical NK cell antigens and mediate natural killing and ADCC. Further characterization of the costimulatory signals for NK cell proliferation may elucidate the physiologic regulation of NK cell growth and may ultimately allow more effective manipulation of these lymphocytes in the immunotherapy of human diseases.

Características organolépticas y físico químicas de propóleos de la provincia de Ñuble, VIII región-Chile / Characteristiques organoleptic and physicochemical propolis in the province Ñuble, VIII region-Chile

El propóleos es una sustancia gomo-resinosa, producto del procesamiento por parte de las abejas (Apis mellifera), de resinas vegetales de variado tipo. Su composición es muy compleja ya que depende de su origen botánico y de las condiciones geográficas y climáticas donde se encuentren las plantas que producen las resinas. El objetivo del presente trabajo fue determinar las características organolépticas y fisico-químicas de propóleos recolectados en los sectores costero, precordillerano y valle central de la provincia de Ñuble, VIII Región, Chile. En las determinaciones físico-químicos se obtuvieron los rangos de valores de: humedad, cenizas, ceras, fenoles totales, flavonoides totales, impurezas mecánicas, tiempo oxidación y solubles en etanol. De acuerdo a estos resultados los extractos de propóleos del sector costero fueron de mejor calidad que los del sector precordillerano, y éstos mejor que los del sector valle central. Los propóleos de los diferentes sectores fitogeográficos se clasifican de acuerdo a la normativa vigente como de alto tenor de flavonoides. Esta homogeneidad se observa también en el contenido de fenoles totales. En general, las propiedades de los propóleos analizados, se sitúan dentro de los parámetros de calidad exigidos por la reglamentación internacional vigente (Reglamento Técnico para la Fijación de Identidad y Calidad de Propóleos del Ministerio de Agricultura de Brasil, 1999

Oncocercosis en el Ecuador: los oncocercomas; III. Aspectos anatomicos y parasitologicos / Oncocercosis in Ecuador: oncocercomas; III. Anatomical and parasitological aspects

Cuatro tipos de oncocercomas fueron encontrados en los focos de oncocercosis en el Río Cayapas, provincia de Esmeraldas: 1) nódulo subcutáneo, joven, único, móvil; 2) nódulo joven, único, fijo, pegado a la piel; 3) conglomerados que se formam por la unión de 4-6 nódulos; 4) nódulos que se forman por la unión de 4-6 nódulos; 4) nódulos en un saco anatómicamente idenficable cuyo pedículo tiene un contenido vascular, linfático y nervioso que provienen de la facia subyacente. La mayor parte de nódulos tuvieron un tamaño pequeño, con un diámetro menor de 1.1 + 0.5 cm y un pesom promedio de 1.4 + 0.9 gr. Sólo 2.0% de los nódulos viejos estuvieron calcificados. Cada nódulo tuvo un promedio de 2.4 gusanos adultos, con 1.5 hembras y 0.9 machos

Oncocercosis en el Ecuador: los oncocercomas; II. Prevalencia en los focos de Esmeraldas / Onchocerciasis in Ecuador: the onchocerca; II. Incidence of focus in Esmeraldas

Nódulos palpables fueron encontrados en un 45.5% de todos los individuos positivos para oncocercosis en la provincia de Esmeraldas, con nódulos que se presentaron más frecuentemente en hombres (49.8%) que en mujeres (39.2%). En relación a la raza, los Chachi se presentaron con más nódulos (48.3%) que los Morenos (38.9%). La mayoría de los nódulos estuvieron localizados en la región pélvica (48.2%) seguidos por la región de la cabeza (21.6%). En niños de edades de 0-12 años, la mayoría de nódulos (83.2%) fueron encontrados en la región de la cabeza, haciendo de ellos uno de los grupos de más alto riesgo para desarrollar lesiones en el ojo. En relación a la endemicidad, 93,6% de todos los nódulos palpables fueron localizados en individuos que viven en áreas hiperendémicas. Un promedio de 1.7 nódulos por portador fue encontrado con el más alto promedio, 1.9 en las áreas hiperendémicas, 1,4 en las mesoendémicas y 1.3 en las áreas hipoendémicas. Hubo una gran variación en la prevalencia de los portadores de nódulos en diferentes comunidades dentro de la misma área endémica, así que no hubo una relación directa entre la prevalencia de los portadores de nódulos, el número de nódulos por portador y la prevalencia e intensidad de la infeccion

Hideyo Noguchi: su vida y su obra / Hideyo Noguchi: its life and its work

Presenta una biograf¡a del japonés Hideyo Noguchi, quien en colabor¢ con una investigación del germen de la fiebre amarilla en el Ecuador...

Leishmaniasis cutánea generalizada: un caso parasitológicamente confirmado en el Ecuador

Un caso de leishmaniasis cutánea generalizada con 308 úlceras costrosas fue reportado. El paciente, una mujer mestiza de 40 años que vino de Balao Chico, Provincia del Guayas. En este caso no se encontró compromiso de membranas mucosas, sino la diseminación de lesiones por toda la superficie del cuerpo. La paciente fue admitida en un hospital de Guayaquil, con el diagnóstico de varicela, paracoccidioidomicosis e infección estafilocócica. El cuadro clínico era controversial y el diagnóstico resultaba difícil. Sin embargo, el examen microscópico de biopsias de la piel de las lesiones reveló amastigotes de Leishmania. Así, se llegó a la conclusión que podría haber la coexistencia con herpes zoster, lo cual en parte explicaría la diseminación de las lesiones ulcerosas...