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991.
BACK GROUND: Although African American breast cancer survivors are most likely to gain weight following diagnosis and treatment compared to women from other ethnic groups, limited information is available on psychological and behavioral reactions to weight change in this population. OBJECTIVES: To explore perceptions and reactions to weight change in African American breast cancer survivors. METHODOLOGY: A parallel mixed methods approach was used to explore experiences with and reactions to weight change following breast cancer diagnosis and treatment. Participants were 16 short- and long-term African American breast cancer survivors. RESULTS: Nine out of 16 participants gained weight following diagnosis and treatment and most participants were concerned about these changes. Most participants were also interested in diet and exercise programs; however, a holistic and common sense approach to diet and physical activity emerged as key themes. CONCLUSIONS: Although prior reports have found that African American women in the general population report a greater tolerance for larger body sizes, most participants in this study were concerned about changes in their weight and were actively trying to minimize weight gain. Several themes emerged regarding physical activity and dietary behaviors; overall, participants described a holistic and practical approach to these behaviors. 相似文献
992.
Polycyclic aromatic hydrocarbons (PAHs) derived from fossil fuels are ubiquitous contaminants and occur in aquatic habitats as highly variable and complex mixtures of compounds containing 2 to 6 rings. For aquatic species, PAHs are generally accepted as acting through either of two modes of action: (1) "dioxin-like" toxicity mediated by activation of the aryl hydrocarbon receptor (AHR), which controls a battery of genes involved in PAH metabolism, such as cytochrome P4501A (CYP1A) and (2) "nonpolar narcosis", in which tissue uptake is dependent solely on hydrophobicity and toxicity is mediated through non-specific partitioning into lipid bilayers. As part of a systematic analysis of mechanisms of PAH developmental toxicity in zebrafish, we show here that three tetracyclic PAHs (pyrene, chrysene, and benz[a]anthracene) activate the AHR pathway tissue-specifically to induce distinct patterns of CYP1A expression. Using morpholino knockdown of ahr1a, ahr2, and cyp1a, we show that distinct embryolarval syndromes induced by exposure to two of these compounds are differentially dependent on tissue-specific activation of AHR isoforms or metabolism by CYP1A. Exposure of embryos with and without circulation (silent heart morphants) resulted in dramatically different patterns of CYP1A induction, with circulation required to deliver some compounds to internal tissues. Therefore, biological effects of PAHs cannot be predicted simply by quantitative measures of AHR activity or a compound's hydrophobicity. These results indicate that current models of PAH toxicity in fish are greatly oversimplified and that individual PAHs are pharmacologically active compounds with distinct and specific cellular targets. 相似文献
993.
McGuire SO Sortwell CE Shukitt-Hale B Joseph JA Hejna MJ Collier TJ 《Nutritional neuroscience》2006,9(5-6):251-258
The exact mechanisms contributing to poor neuronal survival in cell transplantation paradigms for Parkinson's disease (PD) are unknown. However, transplantation-induced host immune response, inflammation, and subsequent oxidative stress are likely contributors to cell death since dopamine (DA) neurons are exquisitely sensitive to oxidative damage. Multiple studies have attempted to improve cell survival by treating transplant material with antioxidant and antiinflammatory compounds, whereas far fewer studies have attempted to modify the host environment to reduce these threats. Flavonoids, phytochemicals found in fruits and vegetables, have antioxidant, antiinflammatory, and immunomodulatory properties. For example, supplementation with dietary blueberry extract (BBE) prevents oxidative stress-associated impairment of striatal motor function during aging and restores lost motor function in aged rats. We hypothesized that dietary supplementation of rodent diets with BBE would improve the survival of embryonic DA neurons transplanted into the unilaterally DA-depleted striatum. Inclusion of 2% BBE in a custom chow diet significantly increased the survival of implanted DA neurons and ameliorated rotational behavior asymmetries as compared to transplanted animals consuming a standard diet. These findings provide support for the potential of dietary phytochemicals as an easily administered and well-tolerated therapy that can be used to improve the effectiveness of DA neuron replacement. 相似文献
994.
Negotiation of the most favorable managed rates may be the best opportunity you have to meet the revenue goals of the practice. When participating in a negotiation you should arm yourself with all the knowledge and tools available. This article discusses some of the public filings made annually by payers and how to use the data, the payer's own data, to enhance your negotiating position. 相似文献
995.
Collier BW Perich MJ Boquin GJ Harrington SR Francis MJ 《Journal of the American Mosquito Control Association》2006,22(3):444-450
The effect of 2 mosquito traps and 2 repellent systems on the catch of adult mosquitoes in American Biophysics Corporation (ABC) light traps was evaluated over a 14-month period at 3 locations in Louisiana. Devices evaluated included 1) ABC Mosquito Magnet with dry ice and octanol; 2) the BioSensory 500 cc Dragonfly Biting Insect Trap with CO2, octenol, and Mosquito Cognito, which uses Conceal inhibitor; 3) the SC Johnson OFF! Mosquito Lantern; and 4) the ThermaCell cordless mosquito repellent system. The number of adult mosquitoes caught in the ABC light traps, at the SC Johnson OFF! Mosquito Lantern, and ThermaCell cordless mosquito repellent treatment sites was significantly lower than the number collected at the ABC Mosquito Magnet or the Dragonfly/Mosquito Cognito trap system sites. When the 2 repellent devices were placed in combination with the ABC traps, mosquito numbers were significantly reduced when compared with sites with ABC traps alone. These data indicate that the SC Johnson OFF! Mosquito Lantern and ThermaCell cordless mosquito system may reduce attack from biting mosquitoes due to the reduction in their numbers. In the same study, the mosquito counts of the trapping devices also were reported. 相似文献
996.
Losanoff JE Collier AD Wagner-Mann CC Richman BW Huff H Hsieh Fh Diaz-Arias A Jones JW 《The Annals of thoracic surgery》2004,77(1):203-209
BACKGROUND: Poor healing of median sternotomy can significantly increase morbidity, mortality, and hospital costs. Effective union requires reliable sternal fixation. Although wire has proven the most reliable and widely used sternotomy closure material, no experimental studies have compared a large variety of wiring techniques in a human model. We developed an easily reproducible experimental model using cadaveric human sterna and compared several wiring methods to assess closure strength and stability. METHODS: Fifty-three fresh adult human cadaveric sternal plates with adjacent ribs were fixed with specially designed spiked stainless steel clamps and attached to a texture analyzer. Single peristernal and transsternal, alternating single peristernal and transsternal, figure-eight peristernal, figure-eight pericostal, and Robicsek closures using no. 5 stainless steel wires were tested. We evaluated bone density, stiffness, and displacement using perpendicular, repetitive variable force loads of 800 Newtons cycling at a rate of 0.5 mm/s. RESULTS: There were no significant differences in age, sex, or bone density in outcome measures of the sternal groups. No clamp failures or clamp damage to the specimens occurred. The single peristernal and alternating peristernal and transsternal closures proved superior in strength and stability (p < 0.001). The figure-eight peristernal, then the single transsternal, then the Robicsek were next stablest groups in decreasing order. The figure-eight pericostal closure had the highest failure rate (p < 0.001). CONCLUSIONS: This novel model of sternotomy closure testing was reliable, inexpensive, and easily reproducible. The mechanical stability of peristernal and alternating peristernal and transsternal wires was significantly greater than that of the other tested methods. Pericostal figure-eight closures were not sufficiently stable to be considered a reliable method of primary sternotomy repair. 相似文献
997.
Collier MB McAuley JP Szuszczewicz ES Engh GA 《Clinical orthopaedics and related research》2004,(423):138-143
The clinical importance of the known proprioceptive deficit in patients with osteoarthritis of the knee is unclear. Attention to the factors that influence proprioception is needed to better understand the role that proprioception plays in the disease process and to assess how these deficits influence clinical outcomes of various treatment options for osteoarthritis. We hypothesized that preoperative proprioception would be poorer in knees with greater symptoms and that knees considered candidates for unicompartmental arthroplasty would have superior proprioception to those in which a total knee arthroplasty was indicated because of the less extensive disease process in the former group. Proprioceptive thresholds were measured in 119 patients with osteoarthritis and no prior knee arthroplasties who were scheduled for unicondylar or total knee arthroplasty. Proprioception examinations consisted of passively flexing and extending each of the bilateral knees in patients independently, from 45 degrees flexion until the blinded patient identified motion. Proprioceptive thresholds for flexion and extension were computed from the angular delays that elapsed before the patient recognized the stimulus. Multiple regression analysis was done to assess the association that these proprioceptive thresholds had with patient factors (age, gender, body mass index, activity level, functional capacity) and knee factors (surgical history, osteoarthritis severity, angular deformity, instability, range of motion). Patient age was the strongest predictor of proprioceptive thresholds, with older patients tending to respond slower to stimulus. Comparison of the right and left knees of each patient showed that proprioception was significantly poorer in the more symptomatic of the two knees. Preoperative thresholds did not differ between knees that received a total knee arthroplasty and those that received a unicondylar arthroplasty. 相似文献
998.
Glutamine supplementation in infants with gastrointestinal disease: a randomized, placebo-controlled pilot trial 总被引:3,自引:0,他引:3
Duggan C Stark AR Auestad N Collier S Fulhan J Gura K Utter S Teixeira-Pinto A Donovan K Lund D 《Nutrition (Burbank, Los Angeles County, Calif.)》2004,20(9):752-756
OBJECTIVE: Glutamine (Gln) is a non-essential amino acid that plays an important role in energy metabolism for gastrointestinal epithelia and other cells with rapid turnover. We evaluated the effects of enteral supplementation with Gln in infants undergoing surgery for congenital or acquired gastrointestinal disease. METHODS: This was a randomized, double-masked, controlled clinical trial. RESULTS: Twenty infants were randomly assigned to receive Gln (n = 9) or placebo amino acid (n = 11), with a goal of supplemental amino acid intake of 0.4 g.kg(-1).d(-1). Infants were weaned from parenteral nutrition, and enteral feeds were started according to a standardized feeding protocol. Median (interquartile range) durations of parenteral nutrition were 39 d (12 to 99) in the Gln group and 21 d (6 to 59) in the control group (P = 0.201). Median (interquartile range) durations needed to reach 80% of the US recommended dietary allowance for energy with enteral nutrition were 24 d (8 to 55) in the Gln group and 12.5 d (5 to 32) in the control group (P = 0.313). There were no differences in the occurrence of infections between groups. Among all infants enrolled, significant correlations were found between duration of parenteral nutrition and residual small bowel length, peak concentrations of direct bilirubin, and alanine aminotransferase. Peak direct bilirubin was associated with longer duration of parenteral nutrition, shorter gestation, older age before feeds were started, shorter bowel length, and larger amounts of parenteral energy and protein intake. CONCLUSIONS: In this pilot trial, enteral Gln supplementation was well tolerated among infants with surgical gastrointestinal disease. There was no effect observed on the duration of parenteral nutrition, tolerance of enteral feeds, or intestinal absorptive or barrier function. Larger, multicenter trials in infants with surgical gastrointestinal disease are needed due to the variability in important outcome measurements. 相似文献
999.
Identifying potential risk haplotypes for schizophrenia at the DTNBP1 locus in Han Chinese and Scottish populations 总被引:4,自引:0,他引:4
Li T Zhang F Liu X Sun X Sham PC Crombie C Ma X Wang Q Meng H Deng W Yates P Hu X Walker N Murray RM St Clair D Collier DA 《Molecular psychiatry》2005,10(11):1037-1044
The dystrobrevin-binding protein 1 (DTNBP1) gene on chromosome 6p has emerged as a potential susceptibility gene for schizophrenia. Although a number of attempts to replicate the original association finding have been successful, they have not identified any obvious pathogenic variants or a single at risk haplotype common to all populations studied. In the present study we attempted further replication in an independent sample of 638 nuclear families from the Han Chinese population of Sichuan Province, SW China. We also examined 580 Scottish schizophrenic cases and 620 controls. We genotyped 10 single-nucleotide polymorphisms (SNPs) in DTNBP1 that were used in the original report of association, plus rs2619538 (SNP 'A') in the putative promoter region, which has also been associated with schizophrenia. In the Chinese trios we found that two SNPs (P1635 and P1765) were significantly overtransmitted, but with alleles opposite to those reported in the original studies. SNPs P1757 and P1765 formed a common haplotype, which also showed significant overtransmission. In the Scottish cases and controls, no individual markers were significantly associated with schizophrenia. A single haplotype, which included rs2619538 and P1583, and one rare haplotype, composed of P1320 and P1757, were significantly associated with schizophrenia, but no previously reported haplotypes were associated. Based on the data from the Chinese population, our results provide statistical support for DTNBP1 as a susceptibility gene for schizophrenia, albeit with haplotypes different from those of the original study. However, our lack of replication in the Scottish samples also indicates that caution is warranted when evaluating the robustness of the evidence for DTNBP1 as genetic risk factor for schizophrenia. 相似文献
1000.
Cho HJ Meira-Lima I Cordeiro Q Michelon L Sham P Vallada H Collier DA 《Molecular psychiatry》2005,10(8):771-781
The serotonin transporter (5-HTT) is a candidate gene for bipolar disorder (BPD). It has been investigated for association with the illness in a series of studies, but overall results have been inconsistent and its role in the disorder remains controversial. Systematic reviews using meta-analytical techniques are a useful method for objectively and reproducibly assessing individual studies and generating combined results. We performed two meta-analyses of published studies--both population-based and family-based studies--investigating the association between BPD and the 5-HTT gene-linked polymorphic region (5-HTTLPR) and the intron 2 variable numbers of tandem repeats (VNTR) polymorphisms. The literature was searched using Medline and Embase to identify studies for inclusion. We statistically joined population-based and family-based studies into a single meta-analysis. For both polymorphisms, our review revealed significant pooled odds ratios (ORs): 1.12 (95% CI 1.03-1.21) for the 5-HTTLPR and 1.12 (95% CI 1.02-1.22) for the intron 2 VNTR. Meta-regression showed that neither the study type (population-based vs family-based; P=0.41 for the 5-HTTLPR and P=0.91 for the intron 2 VNTR) nor the sample ethnicity (Caucasian vs non-Caucasian; P=0.35 for the 5-HTTLPR and P=0.66 for the intron 2 VNTR) significantly contributed to the heterogeneity of the meta-analyses. The observed ORs could be regarded simply as a very small but detectable effect of the 5-HTT, which has an additive effect when combined with other susceptibility loci. Alternative hypotheses on this finding were also discussed: a stronger effect of the haplotypes involving the two polymorphisms or other SNP markers; a more direct effect of these polymorphisms on specific phenotypes of BPD; and the presence of gene-environment interaction as a mediator of the genetic effects of 5-HTT. 相似文献