ACCELERATED PAPER: Lack of association between the polyadenylation polymorphism in the NATl (acetyltransferase 1) gene and colorectal adenomas

Smoking and a high intake of red meat are risk factors for colorectaltumors. These effects could be due to aromatic amine carcinogens.Individual susceptibility to aromatic amines has been relatedto acetylation phenotype, which plays a role in the bioactivationof arylamines. Polymorphisms in both N-acetyltransferase genes,NAT1 and NAT2, have been associated with an increased risk ofcolorectal tumors. We studied the NATl*10 fast acetylator allele(1088 T     

Single-base substitutions give rise to a five-banded DNA profile at the D10S28 locus

Background : DNA profiles from variable number of tandem repeat (VNTR) loci typically are composed of two bands, one derived from each member of the homologous pair of chromosomes. DNA profiles composed of more than two bands result from mutations, and the uestion arises as to the mechanism underlying these unusual multibanded DNA profiles. Study Design and Methods : An alleged father in a paternity test was found to have a five-banded DNA profile at the D10S28 locus when his DNA was subjected to single-locus restriction fragment length polymorphism mapping with the restriction enzyme Pvu II. Results : Several results suggest that this complex DNA profile is the result of several single change within the VNTR locus First, there was no evidence of partial digestion of the DNA with Pvu II. Furthermore, the multibanded allele happened, in this case, to be transmitted to the child, who also showed a five-banded pattern composed of four bands inherited from the alleged father and one band inherited from the mother. Second, digestion of this DNA with Hae III resulted in the visualization of just two bands at the D10S28 locus. Conclusion : The results confirm the notion that mutations at VNTR loci are not always the result of additions or deletions of tandem repeats, but that they can also involve single-base substitutions either within or flanking VNTR loci that give rise to atypical DNA profiles and new alleles at the locus. single-base changes within or flanking VNTR loci that give rise to a typical DNA profiles and new alleles at the locus.     

Transhepatic transcatheter puncture of an occluded biliary intestinal anastomosis for recanalization

A new technique to recanalize a stenosis following hepaticojejunostomy is described. Transhepatic transcatheter puncture of the jejunum is performed followed by dilatation and electroincision of the new track.     

Computer simulation of population dynamics of the American dog tick (Acari: Ixodidae)

A comprehensive computer model was developed for simulation of the population dynamics of the American dog tick (ADT), Dermacentor variabilis Say, in North America. The model simulates the effects of major environmental variables, such as ambient temperature, saturation deficit, kind of habitat, and host density, on ADT population dynamics in ecosystems with small mammals as hosts for immature ticks and medium-sized mammals or domestic dogs as hosts for adult ticks. General validity of the model was established by comparisons between simulated and actual population densities for a series of years at locations in Virginia, Maryland, and Massachusetts using actual weekly weather data for each year as a model input. Using historical-average weather data for 11 locations within the known geographic range of ADT and 3 locations outside this range, the model produced acceptable values for initial population growth rate and generation time, as well as realistic equilibrium population densities and seasonal activity patterns. This model can be used as a framework for additional modeling efforts to simulate the transmission of Rocky Mountain spotted fever and to study various strategies for management of ADT populations.     

Increased granulocyte aggregation in vitro in diabetes mellitus

Having previously shown an increase in white blood cell (WBC) aggregation in groups known to have a high incidence of cardiovascular events, we compared 28 patients with diabetes mellitus and no history or clinical evidence of macrovascular disease with 28 age- and sex- matched normal controls. Patients and controls had blood taken in the morning and analysed for WBC aggregation in vitro using a whole blood technique. WBC aggregation was significantly higher in the diabetic group compared with the normal controls (mean +/- SD 31.10 +/- 10.26% vs. 25.7 +/- 9.38%; p < 0.04, Student t-test). WBC aggregation predates the appearance of clinical symptoms of macrovascular disease in diabetes.