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1.
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies.  相似文献   
2.
34 patients with head and neck cancer were treated with carboplatin and radiation therapy. Eligibility criteria included stage IV biopsy-proven squamous cell carcinoma with measurable disease and no distant metastases, Karnofsky performance status score of 60 or greater, age 18 years or more, no previous radiation therapy and adequate hematological, renal, and hepatic function. There were 27 males and 7 females. Ages ranged from 44-70 years with a median of 57 years. Follow-up ranged from 11-34 months with a median of 21 months. Total tumor doses ranged from 50-55 Gy with additional boosts of 15-20 Gy. Carboplatin was given in a dose of 100 mg/m2 once weekly (26 patients) and 200 mg/m2 once every 2 weeks (8 patients), during the radiation therapy course in all 34 patients. Each dose of carboplatin preceded irradiation. 25 patients responded while 9 did not. There were 19 complete responses (CR) and 6 partial responses. 4/19 CR recurred and 5/9 non-responding patients died of disease. Mild to moderate nausea and vomiting were seen in 52.3% of patients and mucositis was seen in 61.8% of patients. Moderate to severe hematological toxicity was seen in 35.3% of patients. Response rates and toxicity we observed during this study clearly show that the combination of carboplatin and radiation therapy is effective and suitable for the treatment of patients with stage IV head and neck cancer.  相似文献   
3.
68 patients with metastatic squamous-cell carcinoma (SCC) of an unknown primary tumor localized to the neck were treated between 1981 and 1990. There were 11 patients treated with radiotherapy alone, 24 patients treated with surgery and radiotherapy and 33 patients treated with radiotherapy and chemotherapy. Male to female ratio was 1.9:1 and the median age was 55 years (range, 33 to 71 years). 41 (61%) patients had N3 disease, 18 (26%) patients had N2 disease and 9 (13%) patients had N1 disease. The majority of N3 patients were treated with radiotherapy + chemotherapy (n = 17) and surgery + radiotherapy (n = 17). The complete response (CR) to radiotherapy + chemotherapy was 73% with 19 patients having no evidence of disease currently. The median survival time (MST of this group was 34+ months. Of the 35 patients who had surgery and/or radiotherapy, 7 (20%) currently have no evident disease. The MST of these two groups (combined) was 22 months. Patients with N3 disease who received radiotherapy + chemotherapy had a higher CR rate and longer MST when compared with those without chemotherapy.  相似文献   
4.
This project was supported by two separate research grants from the Trust Fund Board, Washington Association for Retarded Citizens to Richard Neel and Truman E. Coggins. The research was also supported by a training grant to the University of Washington entitled Comprehensive Training in Mental Retardation and Other Handicapping Conditions (MCH-000913, Clifford J. Sells, M.D., Principal investigator); and, a training grant to the University of Arizona entitled Doctoral and Post-Doctoral Leadership Training and Clinical Research, Teaching and Administration: Clinical Language Research Center (G008630088, Linda Swisher, Ph.D., principal investigator). We are indeed grateful to the parents of our five subjects for their patience, understanding, and commitment. Finally, we express our appreciation to Arelene Chaussee for her technical expertise and untiring spirit.  相似文献   
5.
Leukotriene B4 (LTB4) and 12(R)-hydroxyeicosatetraenoic acid [12(R)-HETE] are proinflammatory products of arachidonic acid metabolism that have been implicated as mediators in a number of inflammatory diseases. When injected intradermally into the guinea pig, LTB4 and 12(R)-HETE elicit a dose-dependent migration (chemotaxis) of neutrophils (PMNs) into the injection sites as assessed by the presence of a neutrophil marker enzyme myeloperoxidase. SC-41930 {7-[3-(4-acetyl-3-methoxy-2-propylphenoxy)propoxyl]-3,4-dihydro-8-propyl-2H-1-benzopyran-2-carboxylic acid}, a first-generation LTB4 receptor antagonist, inhibited the chemotactic actions of LTB4 when given orally with an ED50 value of 1.7 mg/kg. The second-generation LTB4 receptor antagonist, SC-53228 [(+)-(S)-7-(3-{2-(cyclopropylmethyl)-3-methoxy-4-[(methylamino)carbonyl]phenoxy} propoxy)-3,4-dihydro-8-propyl-2H-1-benzopyran-2-propanoic acid], inhibited LTB4-induced chemotaxis when given intragastrically with an ED50 value of 0.07 mg/kg. Furthermore, SC-53228 inhibited 12(R)-HETE-induced granulocyte chemotaxis with an oral ED50 value of 5.8 mg/kg. When dosed orally over a range of 0.03–100 mg/kg, SC-53228 gaveC max plasma concentrations of 0.015–41.1g/ml. SC-53228 inhibited LTB4-primed membrane depolarization of human neutrophils with an IC50 value of 34 nM. As a potent LTB4 receptor antagonist, SC-53228 may well have application in the medical management of disease states such as asthma, rheumatoid arthritis, inflammatory bowel disease, contact dermatitis, and psoriasis, in which LTB4 and/or 12(R)-HETE are implicated as inflammatory mediators.  相似文献   
6.
Paraneoplastic neurologic syndromes are disorders of the nervous system function caused by cancer but not due to metastatic disease, vascular or metabolic deficits, infections, nutritive deficiency, nor side effects of antineoplastic drugs or irradiation. Immunologic factors probably play the crucial role in the pathogenesis of paraneoplastic neurologic syndromes, but nonimmunologic mechanisms that include metabolic abnormalities and competition for substrate are also involved. Paraneoplastic cerebellar degeneration most commonly occurs in the setting of gynecologic cancers, but it accompanies the small-cell lung cancer too. Other tumors are infrequently associated with cerebellar degeneration. Several paraneoplastic antibodies have been identified in patients with paraneoplastic cerebellar degeneration. Their association with particular cancers may help identify an occult lesion. Anti-Yo antibodies are directed against Purkinje cell antigens and occur in patients with cerebellar degeneration who have breast cancer or gynecologic tumors. A target antigen of anti-Yo antibody is CDR2 protein that is normally expressed only in the brain and testis. Patients with paraneoplastic cerebellar degeneration present with dizziness, nausea and vomiting followed by gait instability, diplopia, gait and appendicular ataxia, dysarthria and dysphagia. Therapeutic options include tumor excision, chemotherapy and/or irradiation, and adjuvant therapy with glucocorticoids, immunoglobulins and plasmapheresis. The role of plasmapheresis in the treatment of paraneoplastic cerebellar degeneration is still uncertain. Reports of its efficacy are anecdotal. We present patient with paraneoplastic cerebellar degeneration with positive anti-Yo antibodies and tumor of the ovaries whose neurologic status significantly improved after four daily plasmaphereses, which was accompanied by a fourfold decrease in the anti-Yo antibodies titer. Further investigations are needed to define a protocol for plasmapheresis in the treatment of patients with paraneoplastic syndromes.  相似文献   
7.
Dietary fat and energy intake have been implicated in breast cancer etiology. To examine the relative importance of these dietary factors on markers of cancer risk in women, we designed an intervention trial to selectively decrease fat and/or energy intake in free-living, premenopausal women who were somewhat overweight. The study used a 2 x 2 factorial design to evaluate the independent and interactive effects of dietary fat and energy. The diets were nonintervention, low fat (15% of energy from fat, maintenance of energy intake), low energy (25% energy reduction), and combination low fat and low energy. We utilized an individualized counseling approach with self-selection of foods. Women on the low-fat and combination diets were asked to meet given daily goals for fat grams and food group exchanges, while women on the low-energy diet used only food group exchanges. Of the 113 premenopausal women randomized who were eligible for analysis, 43% were African-American. A total of 88 women completed the 12-week program, and adherence to the dietary goals was similar in both racial groups. Women on the low-fat diet were able to reduce dietary fat intake to 19% of energy by 4 weeks and to 17% by 12 weeks with a slight decrease in energy intake. Women on the low-energy diet met their energy reduction goals by four weeks while maintaining percentage of energy from fat. Women on the combination diet largely met their goals by four weeks as well. These data indicate that it is possible to selectively manipulate dietary fat and energy intake in women over a short period of time, which makes clinical studies on the relative effects of these two dietary variables on cancer risk biomarkers readily feasible.  相似文献   
8.

Aim

To evaluate the accuracy of eye color prediction based on six IrisPlex single nucleotide polymorphisms (SNP) in a Slovenian population sample.

Methods

Six IrisPlex predictor SNPs (HERC2 – rs12913832, OCA2 – rs1800407, SLC45A2 – rs16891982 and TYR – rs1393350, SLC24A4 – rs12896399, and IRF4 – rs12203592) of 105 individuals were analyzed using single base extension approach and SNaPshot chemistry. The IrisPlex multinomial regression prediction model was used to infer eye color probabilities. The accuracy of the IrisPlex was assessed through the calculation of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the area under the receiver characteristic operating curves (AUC).

Results

Blue eye color was observed in 44.7%, brown in 29.6%, and intermediate in 25.7% participants. Prediction accuracy expressed by the AUC was 0.966 for blue, 0.913 for brown, and 0.796 for intermediate eye color. Sensitivity was 93.6% for blue, 58.1% for brown, and 0% for intermediate eye color. Specificity was 93.1% for blue, 89.2% for brown, and 100% for intermediate eye color. PPV was 91.7% for blue and 69.2% for brown color. NPV was 94.7% for blue and 83.5% for brown eye color. These values indicate prediction accuracy comparable to that established in other studies.

Conclusion

Blue and brown eye color can be reliably predicted from DNA samples using only six polymorphisms, while intermediate eye color defies prediction, indicating that more research is needed to genetically predict the whole variation of eye color in humans.Prediction of human visible characteristics by genotyping informative polymorphisms in DNA opens up a new perspective in the forensic field. Multiple genes including HERC2, OCA2, MC1R, SLC24A5, SLC45A2, TYR, TYRP1, ASIP, SLC24A4, TPCN2, KITLG, and IRF4 have been associated with eye, hair, and skin color in European populations and they have been used in studies dealing with eye color prediction (1-14). Variation of iris color depends on the content of eumelanine, a brown light-absorbing biopolymer, which is present in higher concentrations in brown-eyed individuals (15,16). Although eye color is evidently a continuous variable, it has been often classified into three categories – blue, brown, and intermediate (4,14). Eye color variability is particularly striking in European populations, constituting a highly differentiating trait of potential use in forensic investigations (7,14,17). Recent studies have shown that a significant fraction of human iris color variation can be explained by polymorphisms within a single region in the human genome, comprising the evolutionary conserved HERC2 gene and the neighboring OCA2 gene located on the chromosome 15. It is assumed that the level of expression of the known pigmentation gene – OCA2 – is controlled by polymorphism rs12913832 on HERC2 locus (18,19). The remaining genes that have been shown to contribute to eye color variation are SLC24A4, SLC45A2, TYR, and IRF4 (4,20,21). However, their impact on eye color prediction is lower and it seems to vary between populations (8,14,22,23). Since such differences may potentially affect accuracy of prediction in various populations, we further addressed this issue and analyzed a population sample of individuals with defined eye color from Slovenia.Several prediction models have already been proposed to be useful in eye color prediction (4,8,9,17,23,24). Here we used six IrisPlex predictors, which were selected by Liu et al (4) from a larger set of polymorphisms potentially influencing pigmentation in humans and included into the IrisPlex prediction system (4,13,17). The IrisPlex prediction model is based on a multinomial logistic regression method and uses phenotype and genotype data from 3804 Dutch individuals. Based on these data the model gives three probabilities for blue, brown, and intermediate eye color (13). From the obtained probabilities, the most probable iris color is predicted based on recommendations given in Walsh et al (13).  相似文献   
9.
10.

Background

Oral squamous cell carcinoma (OSCC) constitutes 3 percent of all cancers with predominant occurrence in middle aged and elderly males. Tumour recurrence worsens disease prognosis and decreases quality of life in patients with OSCC. Proinflammatory cytokines such as interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) have been suggested to play a certain role in variety of tumours. The aim of this study was to investigate the relationship of pretreatment serum IL-6 and TNF-α levels on tumour recurrence in patients with OSCC in order to identify potential biomarkers for the early detection of disease recurrence.

Material and Methods

The patients with newly diagnosed OSCC were treated and followed from the first visit from November 2006 until January 2008. Serum IL-6 and TNF-α concentrations were measured. The records of the patients were re-examined in July 2012 and data were recorded about cancer characteristics and tumour recurrence. Disease free survival was analyzed by Kaplan-Meier survival curves, log rank test and Cox proportional hazards regression.

Results

Serum IL-6 was shown as an independent risk factor for tumour recurrence.

Conclusions

Pretreatment serum IL-6 concentration may be a useful biomarker for identification of OSCC patients with increased risk of the disease recurrence. Key words: Serum IL-6, serum TNF-α, oral cancer, recurrence.  相似文献   
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