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101.
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Objective

Demonstrate validity and reliability for an obesity risk assessment tool for young children targeting families' modifiable home environments.

Design

Longitudinal design with data collected over 100 weeks.

Setting

Head Start and the Special Supplemental Nutrition Program for Women, Infants, and Children.

Participants

Parent–child pairs (n?=?133) provided food behavior assessments; 3 child-modified, 24-hour dietary recalls; 3?≥?36-hour activity logs; and measured heights and weights.

Main Outcome Measure

Five measures of validity and 5 of reliability.

Results

Validity was excellent for the assessment tool, named Healthy Kids, demonstrating an inverse relationship with child body mass index percentile-for-age (P?=?.02). Scales were significantly related to hypothesized variables (P?≤?.05): fruit or vegetable cup equivalents; folate; vitamins A, C, and D; β-carotene; calcium; fiber; sugar; screen, sleep, and physical activity minutes; and parent behaviors. Measures of reliability were acceptable.

Conclusions and Implications

Overall, children with higher Healthy Kids scores had a more healthful profile as well as lower body mass index percentiles-for-age 1.5 years later. Healthy Kids has potential for use by nutrition professionals as a screening tool to identify young children most at risk for excess weight gain, as an evaluation to assess intervention impact, and as a counseling tool to tailor intervention efforts. Future research should include validation in other settings and with other populations.  相似文献   
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Objectives The purpose of this qualitative study was to explore the infant safe sleep beliefs and occupational practices of lactation consultants and to determine if lactation consultants give advice to clients that is consistent with the American Academy of Pediatrics’ recommendations on this topic. Methods Focus groups were conducted with certified lactation consultants in two cities in Ohio. Participants discussed the role of lactation consultants, the infant sleep advice they provide to women, their views on the American Academy of Pediatrics’ infant safe sleep recommendations and related policies, and perceived benefits and barriers associated with providing infant safe sleep education as part of their work. A member-checking session was held to ensure the credibility of the findings. Results Four focus groups were conducted with 22 certified lactation consultants between September and November 2015. Major themes that emerged included: lactation consultants’ beliefs regarding the importance of bedsharing for supporting breastfeeding success; their disagreement with the infant safe sleep recommendations of the American Academy of Pediatrics; their frustration with policies that restrict consultants’ ability to discuss bedsharing; and the impact of infant safe sleep policies on their work and the advice they provide. Conclusions for Practice Lactation consultants interact with mothers of newborns at a critical time for infant safe sleep decision-making and may influence a woman’s choices related to this topic. Women may not be receiving messages from lactation consultants that are consistent with the infant safe sleep recommendations of the American Academy of Pediatrics.  相似文献   
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In vitro immunotoxicity of hydrophobic sodium fluoride‐based nanocrystals (NCs) doped with lanthanide ions was examined in this study. Although there is already a significant amount of optical and structural data on NaYF4 NCs, data on safety assessment are missing. Therefore, peripheral whole blood from human volunteers was used to evaluate the effect of 25 and 30 nm hydrophobic NaYF4 NCs dissolved in cyclohexane (CH) on lymphocytes, and of 10 nm NaYF4 NCs on phagocytes. In the concentration range 0.12–75 µg cm?2 (0.17–106 µg ml?1), both 25 and 30nm NaYF4 NCs did not induce cytotoxicity when measured as incorporation of [3H]‐thymidine into DNA. Assessment of lymphocyte function showed significant suppression of the proliferative activity of T‐lymphocytes and T‐dependent B‐cell response in peripheral blood cultures (n = 7) stimulated in vitro with mitogens phytohemagglutinin (PHA) and pokeweed (PWM) (PHA > PWM). No clear dose–response effect was observed. Phagocytic activity and respiratory burst of leukocytes (n = 5–8) were generally less affected. A dose‐dependent suppression of phagocytic activity of granulocytes in cultures treated with 25 nm NCs was observed (vs. medium control). A decrease in phagocytic activity of monocytes was found in cells exposed to higher doses of 10 and 30 nm NCs. The respiratory burst of phagocytes was significantly decreased by exposure to the middle dose of 30 nm NCs only. In conclusion, our results demonstrate immunotoxic effects of hydrophobic NaYF4 NCs doped with lanthanide ions to lymphocytes and to lesser extent to phagocytes. Further research needs to be done, particularly faze transfer of hydrophobic NCs to hydrophilic ones, to eliminate the solvent effect. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Boasso A  Herbeuval JP  Hardy AW  Winkler C  Shearer GM 《Blood》2005,105(4):1574-1581
Indoleamine-2,3-dioxygenase (IDO) and tryptophanyl-tRNA-synthetase (TTS) are interferon-gamma (IFN-gamma)-inducible enzymes that are responsible for tryptophan degradation and for its use in protein synthesis, respectively. IFN-gamma-induced IDO has immunomodulatory properties in murine and human models. A concomitant increase of TTS has been postulated to protect the IDO-expressing cells from tryptophan catabolism. IDO can be induced in dendritic cells (DCs) by recombinant soluble cytotoxic T lymphocyte antigen-4 (CTLA-4-Fc). We investigated the effects of CTLA-4-Fc on IDO and TTS mRNA expression in human peripheral blood mononuclear cells (PBMCs) and isolated leukocyte subsets. CTLA-4-Fc exposure induced increased IDO and TTS expression in unseparated PBMCs, as well as in monocyte-derived mature DCs. CD4(+) T cells isolated from CTLA-4-Fc-treated PBMCs showed increased IDO and TTS compared with untreated cells. CD8(+) T cells from CTLA-4-Fc-treated PBMCs expressed increased levels of TTS but not IDO. Pretreatment of PBMCs with CTLA-4-Fc inhibited the activation of CD4(+) T cells induced by influenza A virus (Flu) or phytohemagglutinin A (PHA), but had no effect on CD8(+) T cells. This is the first report of IDO and TTS regulation by the CTLA-4-B7 system in human CD4(+) and CD8(+) T cells, and raises the possibility that these 2 tryptophan-modulating enzymes provide an important mechanism for regulating immune responses.  相似文献   
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Leptin is the protein product of the obese (ob) gene, a lipostatic hormone that contributes to body weight regulation through suppressing appetite and/or stimulating energy expenditure in humans and/or rodents. In humans, serum leptin concentrations are increased in relation to increased body fat content. Studies have shown a higher leptin level in women compared with men. However, the gender influence on serum leptin concentrations has never been evaluated in patients with type 1 diabetes. In this study, serum leptin levels and percentage body fat mass were measured in men and women with type 1 diabetes. Fasting serum leptin levels were higher in women (16.7 + 11.6 ng/mL) than in men (3.0 +/- 1.5 ng/mL; P < 0.05) and were independent of exogenous insulin intake and of glucose control. Percentage body fat and fat mass were significant determinants of leptin concentration, whereas age and duration of diabetes were not related to leptin concentration. Subgroups of men (n = 12) and women (n = 11) with total body fat between 20 and 30% were compared. Leptin levels were also higher in women compared with men (13.5 +/- 8.3 ng/mL versus 3.2 +/- 1.7 ng/mL; P < 0.05, respectively). In conclusion, our findings indicate that gender is an important determinant of serum leptin concentration in type 1 diabetics, this gender difference is partly explained by body fat distribution and that type 1 diabetic women may be more resistant than type 1 diabetic men to leptin's alleged lipostatic actions.  相似文献   
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