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1.
Driven by research findings regarding the positive relationship between training and enhancement of services, as well as literature on adult learning, the New England Head Start Teaching Center (NEHSTC) was created in 1992 to test the efficacy of participatory, hands-on training. The purpose of this paper is to examine the outcome evaluation results from 4 years of training at the NEHSTC, 1 of 14 federally funded sites, as well as to discuss the implications for delivering this type of participatory training throughout Head Start. Findings suggest that the NEHSTC was successful in implementing high quality, participatory training within the context of an ongoing Head Start program. Head Start staff who participated in the NEHSTC trainings demonstrated gains in knowledge, skills, and expertise compared to similar Head Start employees who did not receive training. Results also reveal a sustained effect of training over time, with NEHSTC participants continuing to demonstrate enhanced knowledge and skills 6 months after training. Similar positive outcomes of training were found for staff with varying levels of experience and holding different Head Start positions. Thus the participatory, hands-on training implemented by the NEHSTC was found to produce positive and lasting outcomes for diverse Head Start staff. An effective and cost efficient model of training Head Start personnel is particularly relevant and timely as Head Start strives to establish universal quality and expansion of services in the 21st Century. The findings are also relevant for improving the quality of all early care and education programs. 相似文献
2.
C L Golas R D Prokipcak A B Okey D K Manchester S Safe T Fujita 《Biochemical pharmacology》1990,40(4):737-741
The competitive binding affinities of thirteen 7-substituted-2,3-dichlorodibenzo-p-dioxins to the human placental cytosolic aryl hydrocarbon (Ah) receptor were determined using [3H]2,3,7,8-tetrachlorodibenzo-p-dioxin as the radioligand. Multiple parameter linear regression analysis of the competitive binding C50 values for these compounds gave the following equation: pEC50 (M) = 6.246 + 1.632 pi - 1.764 sigma 0m + 1.282 HB where pi, sigma m and HB are the physiochemical parameters for substituent lipophilicity, meta-directing electronegativity, and hydrogen bonding capacity respectively. The 7-t-butyl- and 7-phenyl-2,3-dichlorodibenzo-p-dioxins were treated as outliers for the derivation of this equation, and these results suggest that only substituents with van der Waals' volumes less than 40 cm3/mol were accommodated in the receptor binding site. The equations previously derived from the binding of the 7-substituted-2,3-dichlorodibenzo-p-dioxins to the rat, mouse, guinea pig, and hamster hepatic cytosolic receptor were different than the correlation obtained using human placental receptor and provide further evidence for the interspecies differences in the molecular and binding properties of the Ah receptor protein. 相似文献
3.
Nyitrai G Puskás L Antal K Takács V Sass M Juhász G Kardos J Palkovits M 《Neuroscience letters》2005,381(3):344-349
To specify targets for an ischemic preconditioning paradigm (ischemic tolerance), c-fos expressions in ischemic (induced by 10 min bilateral carotid-occlusions subsequent to coagulation of vertebral arteries) and preconditioned rats (treated for 4 min carotid-occlusions 72 h before ischemia) were compared in 12 forebrain areas/nuclei. Fos immunostaining was applied to serial sections of the forebrain and the density (cell number/area measured) of Fos-immunopositive (Fos+) neurons, as well as their percentile changes were determined in five hippocampal and seven extrahippocampal areas/nuclei of ischemic and preconditioned rats. The ratio of counts found in ischemic over control animals showed several fold increase of Fos+ cells in the three layers (granule cell, molecular and polymorphic) of the dentate gyrus, CA3 and CA1 pyramidal neurons, as well as in thalamic and hypothalamic nuclei and limbic cortical areas. In contrast, preconditioning did not alter c-fos expressions significantly in the extrahippocampal brain areas investigated. These results strengthen the hypothesis that the hippocampal and dentate neurons are more susceptible to ischemic tolerance than cells in other brain regions. In fact stress-response and induction of ischemic tolerance in different forebrain areas can be distinguished. 相似文献
4.
Intravascular brachytherapy treatments of in-stent restenosis have been performed extensively using Ir-192 ribbon. Task Group 60 of the American Association of Physicists in Medicine (AAPM) recommends a dose reference point at 2 mm from the source center for these treatments. However, it is known that the source can be as close as 0.5 mm to the arterial wall if not centered in the lumen. Therefore, the source dosimetry needs to be characterized at these close distances to accurately determine the amount of dose delivered for noncentered cases. In this paper, we report the verification of the dose distributions around Ir-192 seed sources at radial distances from 0.5 mm to 6 mm using GAFCHROMIC film. We evaluated an Ir-192 single seed source and a train of 6 seeds spaced 1 mm apart enclosed in a nylon ribbon. Each source was placed in a homogeneous solid water phantom directly below a stack of GAFCHROMIC films (MD-55-2). The calibration curve of the lot of films used in the experiment was established for Ir-192 by exposing a set of calibration films, one at a time, to an Ir-192 high dose rate (HDR) source. All films were scanned 5 or more days after exposure with a Lumisys Model 150 microdensitometer. The data were acquired and evaluated using RIT113 (Radiological Imaging Technology) software and analyzed using Excel and IDL (Interactive Data Language) software. Isodose curve plots in the plane containing the source's longitudinal axis and dose rate plots in the radial direction were obtained. For both configurations, the dose rates along the transverse axes agree to within the margin of error with previous Monte Carlo results. The isodose curve plots display hot spots near the seed ends, which is consistent with the leakage of beta particles and electrons from the unsealed seed ends as predicted with Monte Carlo calculations. 相似文献
5.
Aryl hydrocarbon hydroxylase (AHH, cytochrome P1-450) is highly inducible in several human cells and tissues exposed to specific halogenated and nonhalogenated aromatic chemicals of the "3-methylcholanthrene-type." In laboratory animals AHH induction is known to be regulated by binding of inducers to the Ah receptor, a soluble intracellular protein. However, the induction mechanism in the human species is incompletely understood largely because the Ah receptor, which seems to be essential to the induction process, has not previously been detectable in certain human cells and tissues (including placenta) that are highly responsive to AHH induction. We found that human placenta contains high concentrations of Ah receptor (comparable to the receptor concentrations in rat and mouse liver) but that special modifications were necessary in the assay techniques in order to detect and accurately quantitate receptor binding. Receptor was detected at concentrations approximately equal to 100 fmol/mg cytosol protein using [3H]2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as the radioligand. This high concentration of specific binding sites was present only if the placental tissue was initially homogenized in a buffer containing sodium molybdate (10 or 20 mM). Without molybdate in the homogenizing buffer, specific [3H]TCDD binding was only about 35 fmol/mg. Specific Ah receptor binding also was detectable with [3H]-3-methylcholanthrene and, to a lesser extent, with [3H]-benzo(alpha)pyrene. The receptor sedimented near 9S on sucrose gradients whether molybdate was present or not. About 80% of specific binding was lost if excessive charcoal was used to adsorb "nonspecifically bound" ligand from cytosol prior to gradient analyses. The apparent affinity with which [3H]TCDD bound to Ah receptor in human placental cytosol was relatively low (apparent Kd approximately equal to 5 to 8 nM) when compared with the affinity of [3H]TCDD binding in rat or mouse hepatic cytosols (Kd approximately equal to 1 to 3 nM). These data suggest that while molybdate has very little effect on the quantity or molecular size of the rodent Ah receptor assay, it is very important in stabilizing the human Ah receptor. Our experiments demonstrate that human placenta contains a high concentration of Ah receptor and suggest that AHH induction in placenta is mediated through a receptor mechanism analogous to that previously established in tissues and cells from laboratory animals. 相似文献
6.
Vinícius Raphael de Almeida Borges Marina R. Tavares Julianna Henriques da Silva Lidia Tajber Fabio Boylan Ana Ferreira Ribeiro 《Pharmaceutical development and technology》2018,23(4):343-350
AbstractCopaiba oleoresin (CPO), obtained from Copaifera landgroffii, is described as active to a large number of diseases and more recently in the endometriosis treatment. In this work, poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing CPO were obtained using the design of experiments (DOE) as a tool to optimize the production process. The nanoparticles optimized by means of DOE presented an activity in relation to the cellular viability of endometrial cells. The DOE showed that higher amounts of CPO combined with higher surfactant concentrations resulted in better encapsulation efficiency and size distribution along with good stability after freeze drying. The encapsulation efficiency was over 80% for all produced nanoparticles, which also presented sizes below 300?nm and spherical shape. A decrease in viability of endometrial stromal cells from ectopic endometrium of patients with endometriosis and from eutopic endometriotic lesions was demonstrated after 48?h of incubation with the CPO nanoparticles. The nanoparticles without CPO were not able to alter the cell viability of the same cells, indicating that this material was not cytotoxic to the tested cells and suggesting that the effect was specific to CPO. The results indicate that the use of CPO nanoparticles may represent a promising alternative for the treatment of endometriosis. 相似文献
7.
Malgorzata Kostecka Joanna Kostecka-Jarecka Katarzyna Iowiecka Julianna Kostecka 《Nutrients》2022,14(13)
Celiac disease (CD, enteropathy) is a genetic autoimmune disease (abnormal immune response that attacks healthy tissues) associated with gluten intolerance. The aim of this study was to evaluate and monitor the nutritional status of CD patients, explore the problems associated with diet planning and dietary adherence among children and adults, and assess the impact of these factors on the persistence of CD symptoms. This study was carried out as part of the project entitled “A gluten-free diet without obstacles—eating well and healthy” (POWR 03.01.00-00-T153/18), conducted in Lublin Voivodeship. The study involved 87 persons, including 23 children younger than 18. At the beginning of the study and after nine months, all adult participants (older than 18) were subjected to a body composition analysis with the SECA mBCA 515 analyzer. During the project, the participants attended three consultations with a dietician. During each visit, the subjects’ body weight, nutritional status and diets were evaluated; their diets were modified, and problems relating to dietary adherence were resolved. The initial body composition analysis revealed a risk of sarcopenic obesity in 30% of adult participants, in particular in women (p = 0.003) older than 45 (p = 0.001). The risk of being underweight was diagnosed in 25% of the subjects, in particular, in women younger than 35 (p = 0.0023) and in participants who had been affected by short stature and underweight in childhood, i.e., before CD diagnosis (p = 0.0024). The analysis demonstrated that patients with gastrointestinal symptoms (abdominal pain, diarrhea, vomiting) of CD were significantly more likely to avoid even accidental exposure to gluten and were more likely to strictly follow GFD recommendations (1.97; 95CI:1.56–2.12, p = 0.0001) and safety guidelines when preparing meals at home (1.76; 95CI: 1.34–192, p = 0.0023). Parents, in particular, parents of toddlers and preschoolers who are at significantly higher risk of CD, adhered strictly to dietary guidelines and did not allow for any exceptions when preparing meals (1.88; 95CI: 1.53–2.09, p = 0.001). Persons at risk of malnutrition were also far less likely to deliberately choose gluten-containing foods (0.74; 95CI: 0.53–0.91, p = 0.021), in particular, patients with Marsh type 3a and 3b classification (p = 0.01) and persons whose intestinal histology scores did not fully improve after switching to a GFD. An assessment of the effectiveness of diet therapy based on the phase angle revealed that dietary recommendations had a positive impact on patients who had been recently diagnosed with CD. In all age groups, the main problem was accidental exposure to gluten, in particular in foods that were not labeled with the crossed grain symbol. A comparative analysis of CDAT questionnaires revealed that dietary advice on eating out significantly improved adherence to a GFD and reduced the frequency of unintentional gluten exposure in all age groups. 相似文献
8.
9.
Archives of Sexual Behavior - Adolescents undergo critical developmental transformations that increase the salience of peer influence. Peer interactions (platonic and romantic) have been found to... 相似文献
10.
Interleukin 2 (IL-2) in combination with highly active antiretroviral therapy (HAART) can significantly increase CD4+ T cell counts but does not improve HIV-specific T cell-mediated immune responses that are associated with the control of viral replication. To characterize the immunomodulatory activity of IL-2 in HIV-infected individuals we studied the virus-specific immune response (VIR) by intracellular cytokine expression (interferon gamma, IFN-gamma) after mimicking HIV rebound in peripheral blood mononuclear cells (PBMCs). We found that the whole virus used as HIV antigen was able to activate HIV-specific T cells in the presence of a low concentration (50 IU/ml) of IL-2. Interestingly, increasing concentrations of IL-2 (400 or 1000 IU/ml) in combination with the same amount of HIV doubled the number of HIV-specific T cells. These cells were functionally intact because all of the IFN-gamma-producing CD8+ T cells contained perforin, a marker for cytotoxic T lymphocytes (CTLs). Induction of HIV-specific immune responses by IL-2 was not detected in the absence of HIV antigen both in vitro and in patients treated with HAART, indicating that IL-2 can amplify HIV-specific T cells in the presence of HIV antigen. Therefore, a combination of IL-2 with either structured treatment interruption, which results in a controlled viral load rebound, or with therapeutic vaccination is expected to improve HIV-specific T cell-mediated immune responses. 相似文献