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A goal of the presented study was to analyze and assess the information collected in the assigned electrocardiographic (ECG) arrangement, constituting a "transition" between the two systems of which one is a 87-lead cylindrical system, and the second one is a 30-lead spherical system. The transient 30-electrode arrangement has been selected from the 87-lead ECG network with the arbitrarily assigned electrodes location, which corresponded to the spherical network called "diamentoid". A subject of the visual inspection and analysis were isopotential and isointegral maps created in the three following lead systems: "total", 87-lead cylindrical system; "transient", 30-lead (limited lead) system, and 30-lead spherical system derived from the latter as a result of the diamentoid transformation. The performed comparisons were focused on determining the similarities and differences between the maps gained from the "full" and "limited" lead systems. The maps representing the entire cardiac cycle, constructed on the base of the ECG recordings obtained from the 53 patients, were assessed. The maps, covering the complex QRS divided in the eight portions, were subjected to the detailed analysis. As the result of the comparative analysis of the body surface maps generated in the given three lead systems, it could be concluded that isopotential and isointegral maps from the both 30-lead systems are capable to retain the significant information concerning the features of potentials distribution, as compared with the data provided by the 87-lead system.

To evaluate the prevalence of hepatitis C virus (HCV) infection in children with perinatal human immunodeficiency virus (HIV) infection.Cross-sectional substudy.Multicenter study from 41 sites in the United States.Children with perinatal HIV infection were randomly selected from a large, long-term, follow-up protocol.Hepatitis C infection was defined as having positive test results on both HCV antibody and HCV RNA assays.Five hundred thirty children enrolled in the substudy; definitive HCV test results were available for 525 children. Eighty-three percent were of a minority race or ethnicity. They were equally distributed by sex, had a median age of 10.7 years, and were relatively healthy, with 75% having CD4+ lymphocyte counts greater than 500 cells/mm3. Eight of 525 children (1.5%; 95% confidence interval [CI], 0.7%-3.0%) infected with HIV were coinfected with HCV. In contrast, the rate of HCV infection in a serosurvey of more than 2700 children aged 6 to 11 years from the National Health and Nutrition Examination Survey was 0.2% (95% CI, 0.04%-0.6%). In our study, there were no differences between children coinfected with HIV and HCV and those without HCV infection in terms of demographic characteristics, CD4+ or CD8+ T-lymphocyte counts, HIV 1 RNA levels, preterm or mode of delivery, or liver disease; however, the number of children coinfected with HIV and HCV was small.While HCV prevalence infection rates are low in children with perinatal HIV infection, they are 8 to 10 times higher than reported in HCV serosurveys of children in the United States.

A series of bis-2,7-substituted 1,2,3,6,7,8-hexabydroisoindolo[5,6-f]isoindole-1,3,6,8-tetraones (naphthalene diimides) has been synthesized. The key intermediate required for synthesis of the naphthalene diimides, 2,3,6,7-naphthalenetetracarboxylic dianhydride (2) was prepared starting from allene and maleic anhydride. The bis-anhydride 2 was converted to the naphthalene diimides using conventional methodology by the reaction with amines in organic solvents

Biological samples were collected simultaneously with environmental quality investigations. Studies of metal levels in biological (hair and teeth) and environmental (soil and air) samples were performed in Zwardon during 1991/1992. Zwardon is a small mountain resort village, situated on the border pass of Zwardon, in the close proximity of the southwestern border of Poland. Heavy metal levels in soil, air, and chemical metals forms in the soil were examined. Pearson's product correlation in soil (for total concentration of heavy metals and each chemical form) in hair and in teeth was calculated to investigate bioavailability of heavy metals in human organism. We received essential correlations simultaneously between: Pb vs Mn in exchangeable form of metal in soil, in teeth and in soil (total); Cd vs Zn and Mn vs Co in organically bound form in soil and in teeth and soil (total); and Cu vs Zn in all investigated samples (teeth, hair, soil total, and organically bound form in soil); Mn vs Co and Cr vs Mn in residual form in soil, in teeth, and in soil (total) and between Co vs Ni for hair, soil (total), and residual form in soil.

Heavy metals and Na, Ca, and K were determined in human teeth during 1992/1993 in the Polish towns of Katowice and Istebna. In the relatively clean region of the southern part of Poland (Istebna) the content of heavy metals in the teeth of inhabitants was several times lower than in Katowice (Silesian industrial centre). Ratios of the concentration of Pb : Fe and Pb : Mn in teeth may be an indicator of the pollution. The analysis of the correlation matrix shows the differences in accumulation of metals in teeth for inhabitants of the two investigated towns. The differences of the mean concentration of metals Pb, Ni, Cd, Zn, Co, Mn, Cr, Na and Ca in teeth of inhabitants of Katowice and Istebna were significant (p

The precise carbon-hydrogen correlations of orellanine tetramethyl ether were established by NMR techniques and the methylated alkaloid, as well as some of its structural analogues, was subjected to 1 H NMR experiments with the use of (R)-(+)-t-butylphenylphosphinothioic acid, BINOL or TADDOL as the chiral solvating agents. It was found that tetramethylorellanine, as well as 3,3'-dimethoxy-2,2'-bipyridine-N,N'-dioxide, and some other model compounds gave, in such conditions, proton spectra being composed of separated patterns, each of which corresponds to the individual enantiomer.

The sequential extraction of different metal forms (exchangeable, carbonate, Mn oxides, Mn–Fe oxides, organic, residual) in soil for five locations in Istebna during 1992–93 was performed. Two sites were localized in a ‘clean’ region (national park) and the remaining sites were near a road. Istebna is a small, non-industrial mountain town and the local emission source is the roadway, where the average traffic intensity is about 74 cars per hour. One- and three-way analyses of variance (ANOVA and MANOVA, respectively), were performed to investigate influence of location (roads, ‘clean}’) and the form of metal. Individual metal forms in the soil differ essentially (p < 0.000001). The location was statistically significant at the level p= 0.059, whereas the interaction effect between the location and the type of form was significant at the level P= 0.09.

Polyadenylated RNA was isolated from fibroblast cultures infected with human cytomegalovirus (HCMV) strain AD169 during the late phase of viral replication. The RNA was selected by hybridization to a series of cosmid clones containing the entire viral genome in partially overlapping segments. Translation of this RNA in a reticulocyte cell-free system allowed the mapping of virus specific polypeptides. Nine polypeptides synthesized in vitro comigrated with major virion structural proteins. An in vitro-translated protein of 71 kDa was precipitated by a monoclonal antibody directed against the phosphorylated internal envelope protein of 71 kDa. The map coordinates of viral DNA coding for this phosphoprotein were localized by hybrid selection with subcloned DNA fragments, and the direction of transcription was determined by hybrid selection with single-stranded DNA cloned in bacteriophage vector M13mp9. An in vitro translation with size-fractionated RNA, combined with immunoprecipitation and Northern blot analyses, indicated that an mRNA of 4 kb encodes the 71-kDa phosphoprotein. An mRNA of the same size, map coordinates, and orientation was translated into an abundant 65-kDa polypeptide which had the same size as the major structural phosphoprotein of HCMV.

Aromatic 13C chemical shifts of 4- and 3-substituted pyridine N-oxides in aprotic and protic solvents are reported and discussed. Changes in chemical shifts caused by hydrogen bonding and protonation are much smaller than those induced by a substituent, and are not related to the pKa values of N-oxides. Since the effect of hydrogen bonding is not in the same direction as that due to the substituent effect, the estimation of proton transfer from measured chemical shifts is not possible in complexes of pyridine N-oxides with trifluoroacetic acid. A linear correlation is obtained between the ipso carbon substituent chemical shifts of 4- and 3-substituted pyridine N-oxides and mono-substituted benzenes, which supports the suggestion that electronic factors other than Δq are more important for the ipso carbon.

Pyridinium ylides are formed by deprotonation of the 2- and 6-positions of 3-substituted 1-methoxypyridinium ions in heavy water buffer solutions at 75.0/sup 0/C in reactions catalyzed by deuterioxide ion. Dual substituent parameter equations employing inductive and resonance effects correlate rate constants very well. Both 1- and 3-substituents have an additive influence on the reactivity of the 2-position even when reactivity approaches a diffusion-controlled limit. 1 figure, 2 tables.

Aromatic 13C chemical shifts are reported for 4-substituted and 3-substituted pyridine N-oxides measured in deuteriochloroform, deuterium oxide, perchloric acid (60% in D2O) and dichloroacetic acid (80% in CDCl3), and also for O-alkylated derivatives in (CD3)SO and D2O. The substituent chemical shift (SCS) data show systematic non-additivity in comparison with monosubstituted benzenes. Data for the position para to the variable substituent were analysed by means of the dual substituent parameter equation. For this position multiple substituent interactions are responsible for the non-additive shifts; interactions have both an inductive (polar) and a resonance component. Hydrogen bonding and protonation effects were differentiated from the substituent effect. It is shown that the relative 13C chemical-shift difference [(Δ3–Δ4)/Δ3] is a measure of the hydrogen bond and protonation effects and is not subject to substituent effects. 3-Dimethylaminopyridine N-oxide is protonated at the dimethylamino group, but 4-dimethylaminopyridine N-oxide at the oxygen.