Detection of 1,N2-propanodeoxyguanosine adducts of 2-hexenal in organs of Fischer 344 rats by a 32P-post-labeling technique.

2-Hexenal is an alpha,beta-unsaturated carbonyl compound which is mutagenic, genotoxic and forms cyclic 1,N2-propanodeoxyguanosine adducts like similar propenals for which carcinogenicity was shown, e.g. acrolein or crotonaldehyde. Since humans have a permanent intake of 2-hexenal via vegetarian food this genotoxic compound is considered to play a role in human carcinogenicity. The data base is, however, presently not sufficient for a cancer risk assessment. To date no long term carcinogenicity study on 2-hexenal has been published. Detection of respective DNA adducts of this substance in animals or humans could allow cancer risk assessment. Therefore, we have developed a 32P-post-labeling technique based on nuclease P1 enrichment and TLC separation of the labeled adducts. The respective adducts are stable over a wide pH range from pH 4 to pH 11 and relatively stable against nuclease P1. The detection limit was 0.03 adducts per 10(6) nucleotides and the recovery was 10%. With this method we have shown in vivo formation of 1,N 2-propanodeoxyguanosine adducts of 2-hexenal for the first time and found the respective DNA adducts in different organs of Fischer 344 rats after gavage of 500, 200 and 50 mg 2-hexenal/kg body wt. No adducts could be detected in the organs of untreated rats. There is a clear dependence of the adduct level and the CBI (covalent binding index) on the dose. The CBI of 2-hexenal calculated on the basis of our adduct levels is extremely low (0.06). Since intake of 2-hexenal via fruit and vegetables is very low the cancer risk from 2-hexenal intake via food must also be considered as very low according to a first raw estimation on the basis of CBI and intake. The situation deserves, however, a more precise risk assessment in the future.     

The revival of surgical treatment for isolated proximal high grade LAD lesions by minimally invasive coronary artery bypass grafting.

BACKGROUND: Percutaneous coronary angioplasty (PTCA) and stent implantation have become the first-line intervention for patients with isolated proximal LAD-lesions. Minimally invasive direct coronary artery bypass surgery (MIDCAB) has recently been developed to reduce surgical invasiveness for single LAD revascularization. This study focus on the question whether MIDCAB could be an alternative treatment for isolated proximal LAD lesions. METHODS: Starting in 1996, MIDCAB was performed in 618 patients. Angiography was performed before discharge and repeated after 6 months at follow-up examination. In an ongoing randomized trial 150 patients with an indication for treatment of a LAD lesion have been included to compare the mid-term outcome after PTCA (n=79) vs. MIDCAB (n=71). RESULTS: In 618 MIDCAB procedures 30-day mortality was 0.6%, perioperative myocardial infarction rate was 1.6%. The conversion rate to sternotomy was 3.4%. The learning curve was demonstrated by a patency rate of 96.0% in 1997, 98.0% in 1998 and 99.1% in 1999, respectively. At 6 months patency rate was 94.4% in 1997 and 97.0% in 1998. The rate of severe stenosis >75% dropped from 5.4% in 1997 to 3.4% in 1998. The over all rate of reinterventions was 5.6%. The preliminary result of the randomized trial revealed a difference in the number of perioperative adverse events, 11.4% in the MIDCAB group vs. 6.3% in the PTCA group (P<0.05). At 6 months follow-up 88. 7% of the MIDCAB patients were free from angina vs. 58.2% of the PTCA patients (P<0.02). Restenosis and a positive stress test was diagnosed in 27.9% of the PTCA patients vs. 8.4% of the MIDCAB patients (P<0.02). Reintervention was necessary in 27.9% of the patients after PTCA vs. 8.4% of the patients after MIDCAB. CONCLUSION: MIDCAB is a safe and effective but technically demanding procedure. Perioperative adverse events may be expected, but early as well as mid-term patency rate are good. When compared to PTCA, the freedom from angina and the need for additional revascularization procedures after 6 months is statistically better for patients having MIDCAB surgery. Thus, MIDCAB is considered a valuable alternative for isolated proximal high grade LAD lesions.     

Enabling collaborative research using the Biomedical Informatics Research Network (BIRN)

Objective

As biomedical technology becomes increasingly sophisticated, researchers can probe ever more subtle effects with the added requirement that the investigation of small effects often requires the acquisition of large amounts of data. In biomedicine, these data are often acquired at, and later shared between, multiple sites. There are both technological and sociological hurdles to be overcome for data to be passed between researchers and later made accessible to the larger scientific community. The goal of the Biomedical Informatics Research Network (BIRN) is to address the challenges inherent in biomedical data sharing.

Materials and methods

BIRN tools are grouped into ‘capabilities’ and are available in the areas of data management, data security, information integration, and knowledge engineering. BIRN has a user-driven focus and employs a layered architectural approach that promotes reuse of infrastructure. BIRN tools are designed to be modular and therefore can work with pre-existing tools. BIRN users can choose the capabilities most useful for their application, while not having to ensure that their project conforms to a monolithic architecture.

Results

BIRN has implemented a new software-based data-sharing infrastructure that has been put to use in many different domains within biomedicine. BIRN is actively involved in outreach to the broader biomedical community to form working partnerships.

Conclusion

BIRN''s mission is to provide capabilities and services related to data sharing to the biomedical research community. It does this by forming partnerships and solving specific, user-driven problems whose solutions are then available for use by other groups.     

Differenzialdiagnosen einer schmerzlosen wurzelresorbierenden Raumforderung des Oberkiefers

A 41-year-old male patient was referred because of a root-resorbing lesion in the left upper jaw. The intra-oral examination showed a fistula palatinal and close to tooth 23. The CT investigation confirmed an osteolytic lesion with thinning and partial break through of the vestibular corticalis of the left upper jaw and with resorption of several tooth roots. A biopsy was performed but unspecific. Therefore the lesion was removed completely followed by a detailed histological examination which revealed the presence of an odontogenic fibroma. Odontogenic fibromas are rare odontogenic tumors. Enucleation is the treatment of choice. Relapses have been reported rarely.     

Verhandlungen Ärztlicher Gesellschaften

Ohne Zusammenfassung     

Die Urikolyse

Ohne Zusammenfassung