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11.
Bartczak Andi Weiss; Sangaiah Ramiah; Ball Louise M.; Warren Sarah H.; Gold Avram 《Mutagenesis》1987,2(2):101-105
Many polycyclic aromatic hydrocarbons containing peripherallyfused cyclopenta rings are believed to be activated primarilyby epoxidation of the cyclopenta ring. The cyclopenta epoxidesof a series of four cyclopenta benzanthracene derivatives, benz[e]aceanthrylene-5,6-oxide,benz[j]ace-anthrylene-1,2-oxide, benz(l)anthrylene-1,2-oxideand benz[k]acephenaceanthrylene-4,5-oxide were synthesized fromtheir parent hydrocarbons by formation of the bromohydrin followedby dehydrobromination, and characterized by u.v. vis,and 1H n.m.r. spectroscopy and mass spectrometry. The mutagenicityof these compounds was investigated in the Ames plate incorporationassay with Salmonella typhimurium strain TA98. All the oxideswere active without exogenous metabolic activation (170320His+ revertants per nanomole) and also toxic above 0.5 µg/plate.Addition of S9 protein did not increase, and generally decreased,the mutagenicity of the oxides, while toxicity was largely unchanged.These results are consistent with the postulated role of cyclopentaoxides as major contributors to the mutagenicity of the parentcompounds in the Ames assay. 相似文献
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Jens O L J?rgensen Louise M?ller Morten Krag Nils Billestrup Jens S Christiansen 《Endocrinology & Metabolism Clinics of North America》2007,36(1):75-87
This article focuses on in vivo data from tests performed in normal subjects and in patients who had abnormal growth hormone (GH) status. Experimental data in human subjects demonstrate that GH acutely inhibits glucose disposal in skeletal muscle. At the same time GH stimulates the turnover and oxidation of free fatty acid (FFA), and experimental evidence suggests a causal link between elevated FFA levels and insulin resistance in skeletal muscle. Observational data in GH-deficient adults do not indicate that GH replacement is associated with significant impairment of glucose tolerance, but it is recommended that overdosing be avoided and glycemic control be monitored. 相似文献
15.
Phospho-akt expression is associated with a favorable outcome in non-small cell lung cancer. 总被引:3,自引:0,他引:3
Amit Shah William A Swain Donna Richardson John Edwards Duncan J Stewart Catherine M Richardson Daniel E B Swinson Dipika Patel J Louise Jones Kenneth J O'Byrne 《Clinical cancer research》2005,11(8):2930-2936
Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables.Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037).These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC. 相似文献
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Diego A Preciado Louise Lawson Colm Madden David Myer Chris Ngo John K Bradshaw Daniel I Choo John H Greinwald 《Otology & neurotology》2005,26(4):610-615
OBJECTIVES: To determine whether a stepwise diagnostic paradigm is more diagnostically efficient and cost-effective than a simultaneous testing approach in the evaluation of idiopathic pediatric sensorineural hearing loss (SNHL). DESIGN: Prospective prevalence study. SETTING: Tertiary referral children's hospital. PATIENTS: Consecutive children (n = 150) presenting with idiopathic SNHL in the last 2 years. INTERVENTIONS: All children were evaluated with full diagnostic evaluations including GJB2 screens, temporal bone computed tomography scans, and laboratory investigations. MAIN OUTCOME MEASURES: 1) Diagnostic yields of GJB2 screens, imaging, and laboratory results per SNHL category; 2) Cost analysis comparing a sequential versus a simultaneous testing approach. RESULTS: Overall, 12.0% of patients had biallelic mutations in the GJB2 gene, whereas 30% of patients had an abnormality on temporal bone scan. Laboratory testing did not reveal the SNHL etiology in any patient. While maintaining diagnostic accuracy, significant cost savings were inferred by using a sequential diagnostic algorithm. Our data show children with severe to profound SNHL should first be tested with a GJB2 screen, as opposed to those with milder SNHL, who should undergo imaging as the initial testing step. In patients with initially positive GJB2 or imaging screens, logistic regression analysis significantly predicted negative results on further testing. CONCLUSIONS: A stepwise diagnostic paradigm tailored to the level of the hearing loss in children with bilateral SNHL is more diagnostically efficient and cost effective than the more commonly used full, simultaneous testing approach. Laboratory investigation should not be routine but based on clinical history. 相似文献
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Effect of blockade of TNF-alpha and interleukin-1 action on bone resorption in early postmenopausal women. 总被引:1,自引:0,他引:1
Natthinee Charatcharoenwitthaya Sundeep Khosla Elizabeth J Atkinson Louise K McCready B Lawrence Riggs 《Journal of bone and mineral research》2007,22(5):724-729
After acute estrogen withdrawal in postmenopausal women, administration of anakinra or etanercept, specific blockers of IL-1 and TNF-alpha, respectively, reduced the rise in bone resorption markers to about one half of that in controls. This is consistent with an important role for these immune cytokines in mediating the effect of estrogen deficiency on bone. INTRODUCTION: Studies in rodents have implicated increased production of interleukin (IL)-1 beta and TNF-alpha as mediators of bone loss after ovariectomy, but their roles are unclear in humans whose immune system differs markedly from that of rodents. MATERIALS AND METHODS: We administered transdermal estradiol, 0.1 mg/d, for 60 days to 42 early postmenopausal women. Estrogen treatment was discontinued, and subjects were randomly assigned to intervention groups receiving 3 wk of injections with 0.9% saline, anakinra 100 mg/d, or etanercept 25 mg/twice weekly. Bone turnover was assessed by measuring serum carboxyl-terminal telopeptide of type 1 collagen (CTX) and amino-terminal telopeptide of type 1 collagen (NTX), markers for bone resorption, and serum amino-terminal propeptide of type 1 collagen (P1NP), a marker for bone formation. Results were expressed as percent change in markers from baseline (last 2 days of estrogen treatment and days 20 and 21 of intervention). RESULTS: The percent changes from baseline during intervention for serum CTX, urine NTX, and serum PINP, respectively, were 43.3 +/- 8.0%, 12.0 +/- 7.1%, and -41.0 +/- 2.5% for the control group; 25.9 +/- 6.3%, 9.5 +/- 4.0%, and -37.8 +/- 3.0% for the anakinra group; and 21.7 +/- 5.0%, 0.32 +/- 3.82%, and -34.5 +/- 3.9% for the etanercept group. Compared with the control group, the blunting of the increase in serum CTX fell just below the level of significance (p=0.10) after anakinra treatment, whereas the blunting of the increase in serum CTX (p=0.034) and in urine NTX (p=0.048) were significant after etanercept treatment. Other changes were not significant. CONCLUSIONS: The data are consistent with a role for TNF-alpha, and possibly for IL-1 beta, in mediating increased bone resorption during estrogen deficiency in women. Although either cytokine blocker reduced serum CTX by about one half, the effect of combined blockade could not be tested because of concerns about toxicity. The data do not exclude direct or indirect contributory roles for RANKL or for other cytokines. 相似文献
19.
Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students. 相似文献
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