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41.

Introduction:

The detection of the human papillomavirus (HPV) through the combination of the HPV test and other techniques such as cytology has impacted the detection and timely treatment of lesions associated with cervical cancer.

Objective:

To estimate the budgetary impact of the strategy of early detection of HPV with DNA test genotyping with reflex cytology versus conventional cytology in women aged 30 to 65 years attending the cervical cancer screening program at a health benefit managing entity in Colombia.

Materials and methods:

Using a decision tree and a Markov model, the clinical implications and direct costs of screening, diagnosis, and treatment were estimated in a cohort of women. The analysis considered two screening cycles and their annual costs. The data on the prevalence of clinical results and the costs were taken from the health managing entity. The information on the progression, persistence, and regression of the health states were taken from the ATHENA study.

Results:

The screening scheme with the HPV test, genotyping, and reflex cytology compared to conventional cytology was cost-saving. The average cost per screening cycle with the HPV test was estimated at COP $ 129,201,363 and with cytology at COP $ 186,309,952, i.e., a saving of COP $ 57,108,589 (30.7%).

Conclusion:

The implementation of the screening strategy under evaluation suggests prospective savings derived from the early detection of health states associated with the development of cervical cancer.  相似文献   
42.
Wnt/β-catenin signaling plays an important role not only in cancer, but also in cancer stem cells. In this study, we found that β-catenin and OCT-4 was highly expressed in cisplatin (DDP) selected A549 cells. Stimulating A549 cells with lithium chloride (LiCl) resulted in accumulation of β-catenin and up-regulation of a typical Wnt target gene cyclin D1. This stimulation also significantly enhanced proliferation, clone formation, migration and drug resistance abilities in A549 cells. Moreover, the up-regulation of OCT-4, a stem cell marker, was observed through real-time PCR and Western blotting. In a reverse approach, we inhibited Wnt signaling by knocking down the expression of β-catenin using RNA interference technology. This inhibition resulted in down-regulation of the Wnt target gene cyclin D1 as well as the proliferation, clone formation, migration and drug resistance abilities. Meanwhile, the expression of OCT-4 was reduced after the inhibition of Wnt/β-catenin signaling. Taken together, our study provides strong evidence that canonical Wnt signaling plays an important role in lung cancer stem cell properties, and it also regulates OCT-4, a lung cancer stem cell marker.  相似文献   
43.
Serotonin receptors are potential targets for treating functional bowel disorders. This study investigated the functional roles and expression of the 5-HT4 and the 5-HT7 receptor, which coexist in human colon circular smooth muscle. 5-HT3 receptor expression was also investigated. Part of the relaxant response to 5-HT was due to activation of 5-HT4 receptors as the apparent pKB value of the selective 5-HT4 antagonist, GR 113808, was 9.36. 5-HT4 mRNA levels were low in five tissues and undetectable in four others, but all responded to 5-HT with an EC50 value of 102.54+/-19.32 nM. The contribution of 5-HT7 receptors to the response was not readily demonstrated using the selective 5-HT7 antagonist, SB-269970, as its apparent pKB value of 7.19 (5-HT4 block with 1 microM GR 113808) was lower than the value obtained using the 5-HT7 guinea pig ileum assay (8.62). Nevertheless, the 5-HT7 receptor was expressed more consistently than the 5-HT4, but at similar levels. The 5-HT(3Ashort) and 5-HT(3B) subunits were co-expressed at similar levels, but the 5-HT(3Along) subunit was detected in only five of the nine samples tested. The findings show that 5-HT4-induced relaxation occurs at low to undetectable levels of tissue mRNA, as measured by qPCR. Although 5-HT7 receptor mRNA is detected at low, but consistent levels, the functional activity of this receptor is not readily identified given the currently available drugs.  相似文献   
44.
BackgroundThere is an undefined relationship between access to regional referral centers and whether the eventual oncologic outcomes are influenced by distance, travel time, or residence in a rural community.MethodsWe used the Surveillance, Epidemiology and End Results (SEER) Program Database to capture all cases of high-grade osteosarcoma from 1990 to 2014 in Iowa, Utah, and New Mexico. Using univariate, Kaplan Meier survival analysis, and multivariate Cox proportional hazards modeling we analyzed patient and tumor characteristics.ResultsA total of 476 patients met the study criteria. There was an increased incidence of metastases for patients residing in a county with a greater than 2 -h drive to the nearest comprehensive cancer center (p = 0.021). Individuals residing in “rural” counties and “very rural” counties showed decreased 5-year survival (p = 0.007 and 0.003, respectively) when compared to those living in areas of higher population density. A multivariate regression analysis showed that the presence of metastasis (HR = 2.78 [95% CI: 1.88–4.10], p < 0.0001) and rural status (HR = 1.58 [95% CI: 1.03–2.43], p = 0.037) were risk factors for mortality when controlling for size of the tumor.ConclusionThe travel time to the nearest comprehensive center was associated with an increased incidence of metastasis on presentation in patients with osteosarcoma. Metastasis and rural status were independent risk factors for mortality. This investigation suggests that individuals living in rural counties may experience barriers to presentation, treatment, or surveillance that are not present in areas with a higher population density.  相似文献   
45.
《Cancer epidemiology》2014,38(4):455-459
Physical activity (PA) is related to colorectal cancer (CRC) mortality, with approximately 15% of CRC deaths worldwide attributable to physical inactivity. Moreover, higher levels of PA in CRC survivors have been associated with a reduced risk of the disease recurring. Despite the recognised nexus between PA and the risk of CRC, the physiological mechanisms underlying the inverse relationship between PA and mortality following CRC diagnosis are less apparent, with evidence primarily drawn from epidemiological studies. The insulin-like growth factor (IGF) axis plays a central role in cellular growth, proliferation regulation, differentiation and apoptosis. Specifically, high levels of insulin-like growth factor 1 (IGF-1) have been consistently linked to the severity of CRC tumours. Further, insulin-like growth factor binding protein 3 (IGFBP-3) regulates the bioavailability of IGF-I and therefore plays a central role in CRC prognosis. Decreasing levels of IGF-1 and increasing levels of IGFBP-3 may thus be a plausible mechanism underlying the inverse association between PA and CRC survival.  相似文献   
46.
AimThe aim of this study was to estimate the population-level ‘cure’ of Maltese colorectal cancer patients diagnosed between 1995 and 2004, and to estimate the median survival time for the ‘uncured’ patients.Methods and study populationAnalysis was conducted on 1470 cases registered by the Malta National Cancer Register between 1995 and 2004 and followed up to end of 2010. The mean age of the patients was 66.4 (95%CI 65.8–67.1), and the number of men and women were equal. Background mortality for 1995–2010 was extracted from publicly available life tables. A mixture model with Weibull survival distribution and identity link was used to model ‘cure’.ResultsThe overall ‘cured’ proportion for the patients diagnosed in 1995–1999 was 45.3% (95%CI 40.2–50.5) while the ‘cured’ proportion for the patients diagnosed in 2000–2004 was 52.3% (95%CI 47.2–57.5). Median survival time for the ‘uncured’ patients increased in the second calendar period from 1.25 years (95%CI 1.04–1.45) to 1.42 years (95%CI 1.15–1.76).ConclusionIn Malta, as in the rest of Europe, improvements have been made in short- and long-term survival over the 15-year period under study. To continue this improvement, differences by age that still persist must be investigated and efforts focused to reduce any gaps between Malta and other European countries.  相似文献   
47.
BackgroundIndividuals with Neurofibromatosis Type 1 (NF1) are strongly predisposed to developing pediatric brain tumors (PBTs), especially optic pathway gliomas (OPGs). Although developmental factors have been implicated in the origins of PBTs in both human and animal studies, associations between early-life factors and PBTs have not been evaluated in individuals with NF1. Our objective was to evaluate associations between peri-gestational characteristics and PBTs in this population.MethodsWe conducted a cross-sectional study, ascertaining questionnaire and medical record data for 606 individuals <18 years old who enrolled in the NF1 Patient Registry Initiative (NPRI) from 6/9/2011-6/29/2015. One hundred eighty-four individuals had reported PBT diagnoses, including 65 who were identified with OPG diagnoses. Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between PBT and OPG diagnoses and peri-gestational characteristics (prematurity, birth weight, parental age, plurality, family history of NF1, assisted reproductive technology, maternal vitamin supplementation, and parental smoking).ResultsWe observed no significant associations between any of the assessed characteristics and PBTs overall or OPGs with the exception of birth weight. After controlling for potential confounding variables, we observed a significant positive association between birth weight quartile and OPGs with a HR of 3.32 (95% CI 1.39⿿7.94) for the fourth (⿥3915.5 g) compared to the first (⿤3020 g) quartile (p for trend = 0.001).ConclusionsConsistent with results for PBTs in the general population, these results suggest that higher birth weights increase OPG risk in individuals with NF1.  相似文献   
48.

Aim

To evaluate the association between dose–volume histogram (DVH) values in organs at risk (OAR) and patient-reported HRQoL outcomes.

Background

Data on the association between DVHs and health-related quality of life (HRQoL) in prostate cancer (PCa) patients are limited.

Materials and methods

Five-year follow-up study of 154 patients with organ-confined (stage T1/T2) PCa treated with EBRT between January 2003 and November 2005. HRQoL was evaluated with the Expanded Prostate Cancer Index (EPIC). DVH for OARs (penile bulb, rectum and bladder) were created for all patients for whom data were available (119/154; 77%). The functional data analysis (FDA) statistical method was used. HRQoL data was collected prospectively and data analysis was performed retrospectively.

Results

Worsening of urinary incontinence and obstructive symptoms correlated with higher DVH dose distributions at 24 months. Increased rectal bleeding at months 24 and 60 correlated with higher DVH dose distributions in the 40–70?Gy range. Patients with deterioration in rectal incontinence presented a higher DVH distribution range than patients without rectal incontinence. Penile bulb DVH values and erectile dysfunction were not significantly associated.

Conclusions

DVH parameters and post-radiotherapy HRQoL appear to be closely correlated, underscoring the importance of assessing DVH values prior to initiating EBRT to determine the risk of developing HRQoL related adverse effects. Advanced treatment modalities may be appropriate in high risk cases to minimize treatment-related toxicity and to improve treatment outcomes and HRQoL. Future studies are needed to better elucidate the association between pre-treatment DVH parameters in organs at risk and subsequent HRQoL.  相似文献   
49.
盐酸洛拉曲克在体内、外对S-180细胞株的抗增殖作用   总被引:2,自引:0,他引:2  
研究合合成新型胸苷合成酶抑制剂盐酸洛拉曲克在体内、外对S-180细胞株及正常人胚肾HEK293细胞的抗增殖作用;使用MTT法测定抑制率,以提高荷腹水瘤小鼠存活时间及荷实体瘤瘤重减轻情况为指标考察盐酸洛拉曲克对S-180所致肿瘤的治疗作用。结果表明:在体外盐酸洛拉曲克对S-180肿瘤细胞株有较强的细胞毒作用,对正常细胞HEK293抑制作用较弱(P<0.05);体内实验显示盐酸洛拉曲克可明显提高荷腹水瘤小鼠的存活时间,减轻荷实体瘤小鼠的瘤重,疗效与氟尿嘧啶(10mg/kg)相当(P>0.05)或更好(P<0.05)。可见,盐酸洛拉曲克在体内、外对S-180肿瘤细胞有显著的抗增殖作用,在体外对肿瘤细胞 具有选择性的抗增殖作用。  相似文献   
50.
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