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1.

Introduction

Screening programs for colorectal cancer (CRC) are mainly based on a first-line fecal immunochemical test for hemoglobin (FIT). Fecal M2-type pyruvate kinase (M2-PK) has been evaluated in clinical settings showing promising results for early CRC detection. However, the impact of fecal M2-PK assessment on the performance of first-round CRC screening programs is not known. We investigated whether fecal M2-PK alone or in combination with FIT may improve CRC screening efficacy in the general population.

Materials and methods

A total of 1027 asymptomatic subjects (median age 66 [59-74] years; females 504 [49.1%]), identified through the general practitioners’ rosters, were invited for the collection of 2 fecal samples for FIT and M2-PK evaluation. Participants with at least positive one fecal test were referred for colonoscopy. Quality indicators for screening performance were calculated and analyzed using Fisher’s exact test.

Results

Overall, 572 subjects underwent both FIT and M2-PK assessment (participation rate 55.7%): 93 participants showed positive results for at least one test (positivity rate 16.3%). Only 10 patients were positive for both tests. Attendance rate to colonoscopy was 86.0% and a total of 65 adenomas and 7 cancers were detected. Combined use of FIT and fecal M2-PK permitted the identification of 18 more neoplasm (25%) without improving colonoscopy workload, as deduced by the comparable number needed to scope (P = 0.402).

Conclusion

The addition of M2-PK testing to FIT offers the potential to detect additional neoplasms that either do not bleed or only bleed intermittently without reducing participation rate and without increasing endoscopy workload.Key words: biomarker, colorectal cancer, occult blood, M2-type pyruvate kinase, screening  相似文献   
2.
Knowledge management (KM) has often been claimed to be an essential ingredient in building competitive advantage. Yet, KM adoption is relatively slow, especially in the Malaysian context. Most organizations are unsure if the promised performance improvement is just a passing fad. This study intends to provide empirical verifications to support the link between KM practices and performance outcomes for organizations. Responses from 180 knowledge-based organizations were analysed. The analysis indicated that knowledge acquisition and knowledge utilization positively influenced strategic and operational improvement in organizations, whereas the positive effect of knowledge dissemination was only evident in the case of strategic improvement. Organization size had some interesting moderating impact on the tested relationships.  相似文献   
3.
Experimental model of chronic renal failure in rats have been described by many authors and has also been widely used in various studies. Many of these methods used highly sophisticated instruments which was difficult in our settings. The resection model was ideal in our experimental set-up, but this model had the risk of excessive bleeding and hypovolemia. In our study we used a combination of partial resection and ligation of the renal artery to create two models of stable uremia A and Moderate uremia B. Severe uremia. Both these models were compared with a sham operated group which served as controls. Following surgical procedure, the development of uremia was monitored by serial estimation of blood urea and serum creatinine levels that were measured at regular intervals (bi-weekly). From two weeks onwards the animals in the experimental group showed a significant elevation in the serum urea levels and a consistent elevation in the serum creatinine levels upto eight weeks when compared to the animals in the sham operated group. We established a modified method of producing renal failure which can be maintained for a period of six weeks. This model is simple, reproducible and less complicated that can be used for several studies relating to renal failure in the field of research.  相似文献   
4.
Buccal cell usage has been shown by many to be a cost effective and safe method to isolate DNA for various biological experiments especially large epidemiological studies (Garcia-Closas et al. Cancer Epidemiol Biomarkers Prev 10:687–696, 2001). Non-invasive DNA collection methods are preferred over phlebotomy in order to increase study participation and compliance in research centers and for sick patients in hospital settings. There have been conflicting reports about the methodology and results obtained from using buccal DNA. It is not very clear if phlebotomy can be confidently replaced by buccal cell DNA. It is often left for the user to take an intelligent decision. To address this issue, we compared the performance of buccal and blood DNA from same subjects in a genotyping experiment and this paper reports the results. Cotton swab derived buccal cells were scraped from the inner side of cheeks from 16 subjects, and blood was also drawn from the same 16 subjects participating in a genotypic association study of a lipid disease. The DNA quality was assessed by resolving on agarose gels, checking purity (A260/A280) and finally by microarray hybridization. This study showed that DNA degradation affects the total yield and performance of the buccal DNA when compared to the blood DNA in microarray based genotyping. Genotyping results can be seriously compromised if care is not taken to check the quality and yields of such specimens.  相似文献   
5.
This paper examines the differential effects of green appeals for low involvement and high involvement products. Through a controlled experiment conducted in China, our study demonstrates that for low involvement products, an ad with a green appeal, compared to a similar one without a green appeal, elicits a more favorable consumer attitude toward the ad and the brand. This is true regardless of the level of consumer environmental concern. This study also shows that for high involvement products, there is no interaction effect between green appeals and product involvement. In addition, for consumers with high levels of environmental concern, an ad with a green appeal yields greater purchase intention than a similar one without a green appeal for low involving products. Such an effect is absent for consumers with low levels of environmental concern. Theoretical and practical implications of the findings are also discussed.  相似文献   
6.
Aflatoxins are potent hepatotoxic and hepatocarcinogenic agents. Reactive oxygen species and consequent peroxidative damage caused by aflatoxin are considered to be the main mechanisms leading to hepatotoxicity. The present investigation aims at assessing the hepatoprotective effect of ethanolic leaves extract of Trianthema portulacastrum on aflatoxin B1 (AFB1)-induced hepatotoxicity in a rat model. The hepatoprotection of T. portulacastrum is compared with silymarin, a well known standard hepatoprotectant. Lactate dehydrogenase, alkaline phosphatase, alanine and aspartate aminotransferases were found to be significantly increased in the serum and decreased in the liver of AFB1 administered (1 mg/kg bw, orally) rats, suggesting hepatic damage. Marked increase in the lipid peroxide levels and a concomitant decrease in the enzymic (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and glutathione-S-transferase) and nonenzymic (reduced glutathione, vitamin C and vitamin E) antioxidants in the hepatic tissue were observed in AFB1 administered rats. Pretreatment with T. portulacastrum (100 mg/kg/p.o) and silymarin (100 mg/kg /p.o) for 7 days reverted the condition to near normal. The results of this study indicate that the ethanolic leaves extract of T. portulacastrum is a potent hepatoprotectant as silymarin.  相似文献   
7.
Mobile Phones and the Cultural Ecology of Fishing in Kerala,India   总被引:1,自引:0,他引:1  
Studies that go beyond the ICT4D (Information and Communication Technologies for Development) framework emphasize the social and cultural dimensions of mobile phones. Nevertheless, the cultural dimension, in literature pertaining to both urban and rural use patterns, typically takes an individualistic orientation. The possibility of actualizing the collectivistic logic in a community's appropriation of new technologies is mostly overlooked. The present article explores how the fishers community in Kerala, India, use mobile phones in culturally enhancing and ecologically oriented ways that improve their working and living conditions. In the case of Kerala fishers, the impulse toward cooperation has long been ingrained in their culture, as often happens among marginalized groups. The availability of mobile technologies has allowed for the amplification of this impulse and enabled new modes of cooperation, especially in sharing of information on promising fishing spots and safety and rescue at sea.  相似文献   
8.
As expanded understanding of molecular tumor characteristics, which drive renal cancer growth and progression gives a promising future for renal carcinoma therapy. The objective of the present study was designed to examine the effect of β-sitosterol on a rat model of experimental renal carcinogenesis. Renal carcinogenesis was induced in rats treated with N-diethylnitrosamine (DEN; 200 mg/kg bw single i.p., injection) and ferric nitrilotriacetate (Fe-NTA; 9 mg Fe/kg bw i.p., twice a week for 16 weeks). β-sitosterol pretreatment (20 mg/kg bw in 0.1 % carboxymethyl cellulose (CMC) p.o., thrice a week for 24 weeks) was started 2 weeks before the exposure to carcinogens. Expression of angiogenesis marker (VEGF), proliferative markers (cyclin D1, PCNA) and apoptotic markers (Bcl-2, Bax, caspase-3 and caspase-9) were analyzed to assess the anti-cancer potential of β-sitosterol in renal carcinogenesis model. mRNA and protein expression changes were determined by qRT-PCR, Western blotting, ELISA technique and immunohistochemistry. Our results showed that oral administration of β-sitosterol pretreatment significantly (P < 0.05) reversed the expression of all the above mentioned markers and histological features which have been modified by renal carcinogen. It is concluded that, the protective effects of β-sitosterol against renal cancer is associated with the induction of apoptosis and the inhibition of cellular proliferation.  相似文献   
9.
The study was designed to evaluate the significance of tissue polypeptide specific antigen (TPS) in patients with histologically proven ovarian and colorectal cancer following treatment along with CA125 (in ovarian cancer) and CEA (in colorectal cancer). Patients were grouped as follows:
Group I  : Patients with stable disease
Group II  : Patients with metastasis and relapse
In patients with ovarian and colorectal cancer, the mean TPS levels were significantly higher in patients of group II compared to group I. The percentage of patients above cut-off levels for TPS were 17.4% in group I and 95.5% in group II. Similar results were observed with the mean levels of CA125. In colorectal cancer patients, the percentage of patients above cut-off levels for CEA and TPS were 70% and 30% in group I and 100% in group II for both the markers. Our observations indicate that TPS may be used as a common marker to indicate metastases in patients with ovarian and colorectal cancer.  相似文献   
10.
Ever since its isolation in 1820, Quinine has played a crucial role in the development of organic chemistry, chemical industry and modern medicine. The total synthesis of quinine, widely regarded as anevent of epochal importancewas claimed by Woodward and Doering in 1945. This work, however, heavily relied on unsubstantiated literature reports and it appears that Woodward’s work fell short of a total synthesis of quinine. The first stereoselective total synthesis of quinine was accomplished only in 2001, by Stork, who incidentally is the originator of the concept of stereoselectivity in total synthesis. Naturally, this work has been attested as a landmark in organic synthesis by leaders in the field.  相似文献   
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