DNA-protein interactions in CpG islands and DNAse I sensitive chromatin]

DNA-protein interactions were studied in the chromatin preparations obtained according to different procedures by means of nucleoprotein-celite chromatography. Three discrete fractions dissociating in 1M, 2M and 3M NaCl were observed in all preparations. The 1M fraction prevails in DNaseI-sensitive chromatin and the 2M fraction--in the resistant. Chromatin solubilized by MspI restrictase (the active chromatin) contains the 1M and 3M fractions, one solubilized by AluI (inactive)--the 2M fraction. Distribution of the fractions is different in proliferating and quiescent cells.     

Incidence of leukemias in people aged 0 to 24 in north Cotentin

Multifocal electroretinograms were recorded from twelve subjects on three separate days using the Visual Evoked Response Imaging System (VERIS). The subjects were 18-40 years-of-age. Each recording session was separated by an interval of between one and 16 weeks. Four electrode types were compared: the JET contact lens electrode, the gold foil electrode, the DTL thread electrode and the carbon fibre (c-glide) electrode. The b-wave amplitude density (nV/sq.deg) recorded with each electrode was measured. The mean amplitude density recorded at each session for each subject and each electrode was calculated and compared. There were no significant differences in amplitude density for the ERGs recorded with each type of electrode over the three days. The coefficient of variation for each electrode and each subject was then calculated using the results for the three days. The coefficients of variation for each electrode showed significant differences (One-way ANOVA: F = 4.51, d.f. = 3.44, P < 0.008). The c-glide electrode results had the highest variability and post hoc tests showed that its coefficient of variation was significantly different from those of the JET and gold foil electrodes but not from that of the DTL thread electrode.     

Preservation and peeling of the inferior mesenteric artery in the anterior resection for complicated diverticular disease

The authors, on the basis of 3 cases of complicated diverticular disease, discuss the indications to surgery, considering the advantages and disadvantages of the various surgical techniques and examining in particular the rules for a correct operation with resection and primary or secondary anastomosis. As they performed a rectosigmoidectomy with primary high colorectal anastomosis, they report the reasons why they adopted the preservation and peeling of the inferior mesenteric artery (IMA).     

The genetic sequelae for plant populations of radioactive environmental pollution in connection with the Chernobyl accident

Populations of Arabidopsis thaliana (L.) Heynh., and Pinus sylvestris L., growing within 30 km of Chernobyl and Bryansk region have been analyzed for the frequency of embryonic lethal mutations on Arabidopsis and frequency of chlorophyll mutations and chromosome aberrations by pine. On pine also have been analyzed rate of mutations at enzyme loci in endosperms of seeds. Dose dependence of the value genetic damage on level of radioactive pollution was observed.     

A Ser315Thr substitution in KatG is predominant in genetically heterogeneous multidrug-resistant Mycobacterium tuberculosis isolates originating from the St. Petersburg area in Russia

Parts of katG and rpoB from 27 Russian Mycobacterium tuberculosis isolates were sequenced to detect mutations causing resistance to isoniazid (INH) and rifampin (RMP), respectively. All 24 INH-resistant isolates had a mutated katG, and 22 of them (91.7%) carried a mutation coding for a Ser315Thr shift. An rpoB mutation was noted for each of the 21 RMP-resistant isolates, with Ser531Leu being the most prevalent change encoded. Only two isolates had identical IS6110 fingerprints.     

Compact and rugged all-fibre coupler for wavelength division multiplexing

A very compact and rugged all-fibre coupler for wavelength division multiplexing has been realised. The advantages of this type of coupler are low insertion loss (1 dB?1.5 dB), high crosstalk attenuation (> 35 dB for duplexing), simple and cheap fabrication and excellent stability against environmental factors.