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31.
32.
Robert H. EckelAuthor Vitae Penny Kris-EthertonAuthor Vitae Alice H. LichtensteinAuthor Vitae Judith Wylie-RosettAuthor Vitae Allison Groom Author Vitae Kimberly F. StitzelAuthor Vitae Shirley Yin-PiazzaAuthor Vitae 《Journal of the American Dietetic Association》2009,109(2):288-296
In recent years, epidemiologic and clinical studies, public and regulatory policy activity, and media coverage have focused on issues related to trans fats. To help increase awareness and understanding of trans fats and other fats, the American Heart Association (AHA) launched the “Face the Fats” national consumer education campaign in April 2007. The AHA commissioned a quantitative tracking survey between 2006 and 2007 to measure changes in consumer awareness, knowledge, and behaviors related fats and oils and their perceived impact on heart disease. The survey was conducted by Cogent Research. Data were collected during March 2006 and May 2007. At both time points, the survey included a representative sample of the American population age 18 to 65 years (n=1,000). The sampling plan for the survey was designed based on the 2000 and 2003 US Census. The margin of error was ±3.10 percentage points. Awareness of trans fats increased during the 1-year study period. In 2007, 92% of respondents were aware of trans fats, an increase from 84% in 2006 (P<0.05). The 2007 level was similar to the awareness of saturated fats (93%). Perceptions that certain fats and oils heighten the risk of heart disease increased for trans fats (73% in 2007 vs 63% in 2006; P<0.05), saturated fats (77% in 2007 vs 73% in 2006; P<0.05), and partially hydrogenated oils (56% in 2007 vs 49% in 2006; P<0.05). Knowledge about food sources of different fats remained low. On an unaided basis, 21% could name three food sources of trans fats in 2007, up from 17% in 2006 (P<0.05). Knowledge of food sources of saturated fat remained unchanged at 30% in 2007. Significantly more respondents in 2007 reported behavioral changes related to trans fat information, such as buying food products because they show “zero trans fat” on labels or packages (37% in 2007 vs. 32% in 2006; P<0.05). Between 2006 and 2007, consumer awareness about trans fats increased and attained awareness levels similar to saturated fats. The increased awareness is associated with improved self-reported behaviors in grocery shopping. Nonetheless, overall knowledge, especially regarding food sources of saturated and trans fats, remains relatively low, underscoring the need for heightened consumer education activities. The positive change in consumer awareness about trans fats is likely attributable to the wide range of messages available to them, including the AHA “Face the Fats” national consumer education campaign. 相似文献
33.
Kimberly A. Varker Edward W. Martin Dori Klemanski Bryan Palmer Manisha H. Shah Mark Bloomston 《Journal of gastrointestinal surgery》2007,11(12):1680-1685
Background
Transarterial chemoemobolization (TACE) is commonly used to treat metastatic carcinoid tumors; however, the management of
progressive disease is less clear. We sought to determine if patients with disease progression after TACE would benefit from
repeat TACE.
Methods
The records of 27 patients undergoing repeat TACE for radiologic or symptomatic progression after TACE for metastatic carcinoid
were reviewed and compared to 122 undergoing first TACE. Overall and progression-free survivals were estimated by the Kaplan–Meier
method.
Results
Mean disease-free interval after first TACE was 11.8 months. Radiologic response was observed in 61% compared to 82% after
first TACE (p = 0.058); hormone response in 64% compared to 80% (p = 0.159); and symptomatic response in 77% compared to 92% (p = 0.053). The complication rate after repeat TACE was lower than after first TACE (p = 0.03). Median overall survival was similar after repeat (28.1 months) and first TACE (33.3 months) (p = 0.53). Progression-free survival was shorter after repeat TACE but not significantly so. No factor examined could predict
survival after repeat TACE.
Conclusion
Repeat TACE for patients with hepatic carcinoid metastases failing first TACE or having evidence of disease progression is
safe and offers a viable treatment option.
Presented at the 48th Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, DC, May, 2007. 相似文献
34.
35.
Liposome-mediated transfer of vascular endothelial growth factor cDNA augments survival of random-pattern skin flaps in the rat. 总被引:6,自引:0,他引:6
Paul Y Liu Wenjing Tong Kan Liu Sang Hoon Han Xiao Tian Wang Evangelos Badiavas Kimberly Rieger-Christ Ian Summerhayes 《Wound repair and regeneration》2004,12(1):80-85
Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene. 相似文献
36.
Diana H. Yu BA ; Kimberly A. Mace PhD ; Scott L. Hansen MD ; Nancy Boudreau PhD ; David M. Young MD 《Wound repair and regeneration》2007,15(5):628-635
Insulin-like growth factor-1 (Igf-1), a critical mediator of tissue repair, is significantly decreased in diabetic wounds. Furthermore, decreased levels of hypoxia-inducible factor 1-alpha (Hif-1alpha) and its target genes are also associated with impaired wound healing in diabetic mice. The aim of our study was to examine whether the reduced levels of Igf-1 are responsible for the reduction in Hif-1alpha protein synthesis and activity in diabetic wounds. We provide evidence that Igf-1 regulates Hif-1alpha protein synthesis and activity during wound repair. In addition, Igf-1 stimulated phosphytidylinositol 3-kinase activity in diabetic fibroblasts, which, in turn, increased activation of the translational regulatory protein, p70 S6 kinase. Moreover, improved healing of diabetic wounds by addition of recombinant IGF-1 protein was associated with an increase in Hif-1alpha protein synthesis and function in vivo. 相似文献
37.
38.
Although glucocorticoid hormones have important roles in the development of neurotransmitter systems in cells derived from the neural crest, it is not known whether they have parallel effects on neuronal development in the brain. To address this issue, we have established an in vitro system of fetal medulla oblongata (MO) to follow development of the epinephrine-synthesizing enzyme, phenylethanolamine N-methyltransferase (PNMT). Embryonic MO was explanted from E13 or E18 embryos and maintained for up to 3 weeks. Successful culture of adrenergic neurons was possible only in explants taken from young embryos, since E18 explants failed to develop. In E13 explants, immunoreactivity to both PNMT and tyrosine hydroxylase, the rate limiting enzyme in catecholamine synthesis, was observed. PNMT catalytic activity which was barely detectable at the time of explanation increased markedly during the first week in vitro. To study the effects of glucocorticoids on PNMT development in central neurons, MO explants were grown in glucocorticoid deficient medium in which rat serum from adrenalectomized rats was substituted for human placental serum. Addition of natural glucocorticoids, cortisol or corticosterone, or the mineralcorticoid, deoxycorticosterone, during the third culture week had no effect on PNMT activity. Dexamethasone (DEX), a synthetic glucocorticoid, also had no effect on PNMT during the first or second weeks in culture. However, addition of DEX during the third culture week resulted in a doubling of PNMT activity. However, attempts to block the DEX effect during the third week or to block the increase in PNMT activity during the first week in control cultures with the glucocorticoid receptor antagonist, dexamethasone 21-mesylate, were unsuccessful. These results suggest that PNMT in central neurons does not require glucocorticoids for ontogeny during the embryonic period. This is in contrast to PNMT in adrenal medulla which requires glucocorticoids for normal development during both the embryonic and postnatal periods. More generally, these studies suggest that development of the same neurotransmitter phenotype in brain and periphery may be differentially regulated. 相似文献
39.
Non-clastogenicity in mouse bone marrow of fructose/lysine and other sugar/amino acid browning products with in vitro genotoxicity 总被引:1,自引:0,他引:1
J T MacGregor J D Tucker I I Ziderman C M Wehr R E Wilson M Friedman 《Food and chemical toxicology》1989,27(11):715-721
Heated sugar/amino acid reaction mixtures, known to contain products that are clastogenic and/or mutagenic to cells in vitro, were evaluated for clastogenic activity in mouse bone marrow using the erythrocyte micronucleus assay. Heated (i.e. browned) fructose/lysine reaction mixtures were also evaluated in the Salmonella his-reversion assay and the Chinese hamster ovary (CHO) cell chromosomal aberration assay to confirm and extend previous in vitro observations. Significant mutagenicity of fructose/lysine mixtures was observed in Salmonella typhimurium strains TA100, TA2637, TA98 and TA102, with greater activity in mixtures heated at pH 10 than at pH 7. S-9 decreased the activity in strains TA100, TA2637 and TA98, but increased the activity in strain TA102. Both pH 7 and pH 10 reaction mixtures of the fructose/lysine browning reaction were highly clastogenic in CHO cells. Heated mixtures of fructose and lysine, and of glucose or ribose with lysine, histidine, tryptophan or cysteine, did not increase the frequency of micronucleated erythrocytes in mice when administered by the oral route. This indicates the absence of chromosomal aberrations in erythrocyte precursor cells, and indicates that the genotoxic components of the browned mixtures are not absorbed and distributed to bone marrow cells in amounts sufficient to induce micronuclei when given orally. Because sugar/amino acid browning reactions occur commonly in heated foods, it is important to evaluate further the in vivo genotoxicity of browning products in cell populations other than bone marrow. 相似文献
40.
S. Friedman R. Komorowski W. Maillet H. Q. Nguyen C. D. Torneck 《Dental traumatology》1998,14(5):225-231
Abstract— NdYAG laser-induced modification of the root surface may inhibit development of external inflammatory resorption in replanted teeth. This study tested this hypothesis in vivo. The pulp chambers of six mandibular premolars in each of two dogs were accessed, inoculated with plaque, and sealed (Groups 1, 2). Two additional premolars in each dog were endodontically treated without inoculation (Groups 3, 4). After 2 weeks, teeth were hemisected and extracted. Each root had a 2times3 mm surface area denuded of cementum on the buccal and lingual surface. In Groups 1 (n= 12 roots) and 3 (n=4), the denuded surfaces were wiped with 15% EDTA, coated with black ink, and irradiated with Nd:YAG laser (0.75 W, 15 ppc, 300 pm tip, 20 s). In Groups 2 (n= 12) and 4 (n= 4), the surfaces were wiped with 15% EDTA, and rinsed with sterile saline for 20 s. Roots were replanted within 5 min. The dogs were perfwion-euthanised 10 weeks after replantation. Block specimens were removed, decalcified, embedded and horizontally sectioned (6 pm) at 180-pm intervals, resulting in 10 to 14 cross-sections of each root. From these, the middle five consecutive sections were stained with hematoxylin and eosin, and observed by light microscopy for occurrence of surface, inflammatory and replacement resorption on the denuded surfaces. No obvious differences were noted between the laser-irradiated and non-irradiated surfaces. Inflammatory resorption was frequent in Groups 1 and 2, and absent in Groups 3 and 4. Replacement resorption was minimal in Groups 1 and 2, and frequent in Groups 3 and 4. Differences between Groups 1 and 2, and between Groups 3 and 4 were not significant, whereas the differences between the two pairs of groups were statistically significant (chi-square and two-way ANOVA, P>0.006). These results did not support the hypothesis, and questioned the clinical validity of the surface modification in NdYAG laser-irradiated den-tin. Therefore, the clinical application of NdYAG laser to the root surfaces of replanted teeth is not warranted. 相似文献