Evaluation of antibody against AR142, a synthetic peptide derived from the core sequence of hepatitis C virus, in the diagnosis of non-A, non-B chronic liver disease

We evaluated serum anti-hepatitis C virus (HCV) using a synthetic peptide (AR142) which includes an epitope in the core region of HCV. The incidence of anti-AR142 in 98 patients with type non-A, non-B chronic liver diseases (NANB-CLD) was 89.8%, while all the 28 patients with non-type C chronic liver diseases were negative for anti-AR142. Among 98 NANB-CLD patients, 74 were positive for both anti-AR142 and anti-C100-3, 23 showed discordant results, and one was positive for neither. Eighty-one NANB-CLD patients underwent reverse transcription-polymerase chain reaction assay to detect viremia and 76 (93.8%) had a detectable level of HCV-RNA. Titers of anti-AR142 were not different among groups of different disease activities, genotypes of HCV, nor amount of serum HCV-RNA. These observations suggest that anti-AR142 could be a useful marker for chronic HCV infection.

The Azotobacter chroococcum hydrogenase gene cluster: sequences and genetic analysis of four accessory genes, hupA, hupB, hupY and hupC

The Azotobacter chroococcum chromosome contains a region spanning about 14 kb associated with hydrogen-uptake (Hup) activity. The small and large subunits of the hydrogenase are encoded by the structural genes hupS and hupL. Two other genes, hupD and hupE, are located 8.9 kb downstream from hupL and are required for the formation of a catalytically active hydrogenase. In this study, we determined the nucleotide sequence of a 3.8-kb region immediately upstream from hupD. This revealed four additional closely linked ORFs which we designated hupA, hupB, hupY and hupC; these genes potentially encode polypeptides with predicted masses of 12.6, 33.3, 80.4 and 9.0 kDa, respectively. This cluster of genes was shown to be essential for hydrogenase activity by insertion mutagenesis using antibiotic-resistance gene cassettes and a Tn5 derivative carrying a promoterless lacZ gene. A 10.5-kb fragment of DNA beginning 3.4 kb downstream from hupL, and including the sequenced region, was able to complement hupA and hupY mutants, supporting earlier evidence for a promoter downstream from hupSL. The deduced amino acid sequences of hupA, hupB and hupC are homologous to the Escherichia coli hypA, hypB and hypC gene products, respectively. Of particular interest is the fact that there is no homologue of the hupY gene product in the E. coli hyp operon. Mutations in hupY or hupB had little effect on beta-galactosidase activity in a strain also carrying a hupL::lacZ fusion, showing that hupY and hupB are not major factors in regulating the transcription of the hydrogenase structural genes.

Characterization of two genes (hupD and hupE) required for hydrogenase activity in Azotobacter chroococcum

In Azotobacter chroococcum the hydrogenase structural genes (hupSL) cover about 2.8 kb of a 15-kb region associated with hydrogen-uptake (Hup) activity. Two other genes in this region, hupD and hupE, were located 8.9 kb downstream of hupL and were shown to be essential for hydrogenase activity by insertion mutagenesis. A fragment of DNA beginning 3.4 kb downstream of hupL was able to complement the hupE mutant, supporting earlier evidence for a promoter downstream of hupSL. Hybridization experiments showed that hupD and hupE share some similarity with a region of Alcaligenes eutrophus DNA which is apparently involved in the formation of catalytically active hydrogenase. The hupD gene encodes a 379-amino acid, 41.4-kDa polypeptide while hupE codes for a 341-amino acid, 36.1-kDa product. The predicted amino acid sequences of the hupD and hupE genes are homologous to the Escherichia coli hypD and hypE gene products, respectively. A polar mutation in hupD had no effect on beta-galactosidase activity in a strain also carrying a hupL-lacZ fusion, indicating that hupD and hupE are probably not involved in regulating hydrogenase structural gene expression.

[The effect of fluorine on the developing human brain]

Fifteen therapeutically aborted fetuses at the 5th-8th gestation month from the endemic fluorosis area were compared with those from the non-endemic area. Stereological study of the brains showed that the numerical density of volume of the neurons and the undifferentiated neuroblasts as well as the nucleus-cytoplasm ratio of the neurons were increased. The mean volume of the neurons was reduced. The numerical density of volume, the volume density and the surface density of the mitochondria were significantly reduced. The results showed that chronic fluorosis in the course of intrauterine fetal life may produce certain harmful effects on the developing brain of the fetus.

Structure of 1,1-dichloro-2-(4-methoxyphenyl)-2,3-diphenylcyclopropane

C22H18Cl2O, M(r) = 369.3, monoclinic, P2(1)/a, a = 16.585(1), b = 17.328(1), c = 13.192(3) A, beta = 107.443(8) degrees, V = 3616.8 A3, Z = 8, Dx = 1.356 g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 3.2 cm-1, F(000) = 1536, T = 138 K, R = 0.039 for 5450 observed reflections. The structural features of the two independent molecules are quite similar except in the orientation of the methoxy group. The cyclopropane ring shows the expected bond-length asymmetry with C(2)-C(3) as the longest bond. The two cis-arranged phenyl rings adopt similar conformations as observed in diaryl-cyclopropanes, with one ring in the bisecting position and the other near the perpendicular position. The conformation of the third aryl ring is also near the perpendicular position. The overall conformation of the three aryl rings is different from the helical propeller conformation consistently observed in tamoxifen and all other known tri(tetra)aryl-vinyl systems.

Spatial frequency of the human short-wavelength-sensitive (blue) cone mechanism. Psychophysical studies and pattern-reversal visual evoked potentials

The interactions of spatial and chromatic processing of the short-wavelength-sensitive cone mechanism were studied in humans with patterned (checkerboard) stimuli of various spatial frequency (10, 22, 44, and 85 min of are respectively), under steady exposure to yellow light (575 nm, 390 cd/m2). Psychophysical studies and pattern-reversal visual evoked potentials were employed. Parameters of the transient pattern-reversal visual evoked potentials (pattern reversal rate of 2.4 s-1) especially observed were the latencies of P2 (P100) and N3 and the amplitude of P2-N3. It was only with the largest applicable check size (85 min of arc) that both the psychophysical studies and visual evoked potentials could succeed in satisfactorily isolating the short-wavelength-sensitive cone mechanism. Pattern-reversal visual evoked potential latencies are recommended in the evaluation of this cone mechanism because of their smaller variance and higher selectivity in isolating the short-wavelength-sensitive cone mechanism than the amplitude. The peak sensitivity of this cone mechanism was shown to be about 449 nm at the corneal level. The short-wavelength sensitive cone mechanism represented the characteristics of low spatial resolution and long latencies of the pattern-reversal visual evoked potentials.

Effect of isoelectric point on biodistribution and inflammation: imaging with indium-111-labelled IgG

Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge of the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its isoelectric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats with Escherichia coli thigh infections. The biodistribution was significantly affected by pI. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3-2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.

Recent trends in the registration of blindness and partial sight in Leicestershire

A study is reported of all new registrations for blindness and partial sight in the county of Leicestershire, England, for the years 1965, 1975, and 1985. The number of new registrations for blindness has risen considerably over this period, but the increase is shown to be attributable to changes in the age structure of the population and under-registration in 1965. The number of new registrations for partial sight has also increased over the study period but by significantly more than would be expected, even after changes in the population structure are allowed for. The registration rates for Leicestershire when analysed by age, sex, and cause are shown to be broadly in line with available national figures. Registration rates for macular degeneration and glaucoma are increasing in both males and females, and rates for cataract are at a significantly higher level for women than for men.