Immune status in preschool children born after mass hepatitis B vaccination program in Taiwan

A mass hepatitis B vaccination program began in Taiwan in 1984. In order to determine the immune status of hepatitis B virus (HBV) infection among preschool children, a total of 25 kindergartens in 20 townships and metropolitan precincts in central Taiwan were randomly selected through stratified sampling. Serum specimens of 2130 healthy preschool children aged 2-6 years old were screened for the HBV markers and liver function in 1996. HBV surface antigen (HBsAg), antibody against HBsAg (anti-HBs) and antibody against HBV core antigen (anti-HBc) were tested by reverse passive hemagglutination (RPHA), enzyme immunoassay (EIA) and radioimmunoassay (RIA) using commercial kits. HBV vaccination rate of the preschool children was 98%, and complete vaccination rate (three or four doses of HBV vaccine) was 94%. The HBsAg seropositive rate was 4.5% among incomplete vaccinees and 1.3% among complete vaccinees. The anti-HBs was detectable in 1637 of 2000 complete vaccinees (81.9%) and in 53 of 88 incomplete vaccinees (60.2%). The overall prevalence rate of anti-HBc was 2.4% (52 of 2130). The older the age, the lower the anti-HBs seropositive rate. The anti-HBs seropositive rats for complete vaccinees were 100% at 2 years old and 75% at 6 years old. There were no significant differences in HBsAg-seropositive rates and anti-HBs-seropositive rates among different residential areas or ethnic groups. There were three children who were seropositive on HBsAg, anti-HBs and anti-HBc, whether they were infected by the vaccine-induced escape mutant of HBV deserves scrutiny.     

Preterm birth in rats produced by the synergistic action of a nitric oxide inhibitor (NG-nitro-L-arginine methyl ester) and an antiprogestin (onapristone)

In these experiments we have studied the in vitro metabolism of LVV-hemorphin-7 in human plasma by using reversed-phase high-performance liquid chromatography (RP-HPLC) in combination with micro-electrospray mass spectrometry (micro-ES-MS). Tandem mass spectrometry (MS-MS) was performed in order to verify the structure of the peptide fragments found. Incubations were performed with and without different protease inhibitors. Results showed that LVV-hemorphin-7 was metabolized from the N-terminal end of the peptide, probably by an amastatin-sensitive exopeptidase.     

Humoral response to hsp 65 in multiple sclerosis and other neurologic conditions

The expression of heat shock proteins (hsp) within the target organ is implicated in the pathogenesis of a number of diseases of suspected autoimmune etiology, including MS. To pursue the potential role of a humoral response to the hsp 60/65 kd family in MS, we studied serum and CSF by Western blotting using recombinant Mycobacterium bovis hsp 65 and human hsp 60 as antigens and compared the findings with samples from patients with other neurologic diseases (OND). Analysis of the IgG response in CSF from 18 patients with MS indicated moderate reactivity in 10 cases and no reactivity in eight. In the OND group, reactivity was found in the CSF from one of two patients with Parkinson's disease, four of four Alzheimer's disease patients, and two of two patients with amyotrophic lateral sclerosis. CSF samples from seven of seven patients with subacute sclerosing panencephalitis were negative, as were samples from two normal subjects. There was no reactivity in CSF from two Huntington's disease patients. We conclude that antibodies reactive with hsp 60/65 are present in CSF of some MS patients but are also present in a number of chronic neurodegenerative conditions. The findings indicate that a humoral response to hsp 60/65 in the CSF is not specific for MS.     

Polymorphonuclear neutrophil chemotaxis in Chinese patients with post-juvenile periodontitis and rapidly progressive periodontitis

The purpose of this study was to investigate polymorphonuclear neutrophil (PMN) chemotaxis in Chinese patients with post-juvenile periodontitis (post-JP) and rapidly progressive periodontitis (RPP). Peripheral blood PMNs were isolated from nine post-JP and 13 RPP patients. Eight patients with adult periodontitis (AP) and seven clinically healthy subjects were used for comparison. Clinical data, including the plaque index and gingival index, of each subject were recorded. The "modified Boyden chamber technique" was used for PMN chemotaxis assay. Our results showed that the PMN chemotaxis index in patients with post-JP and RPP were significantly depressed compared to that in healthy subjects or patients with AP. There was no significant difference in PMN chemotaxis between post-JP and RPP, or between AP and healthy subjects. There was also no significant correlation between the plaque index, or gingival index, and PMN chemotaxis in any group. These results suggest that there is a PMN chemotaxis defect in most Chinese patients affected by post-JP or RPP, and that the PMN chemotaxis defect is not associated with clinical parameters such as the plaque index or gingival index.     

Receptors for polytropic and xenotropic mouse leukaemia viruses encoded by a single gene at Rmc1

The onset of leukaemia caused by type C retroviruses (MLV) in mice is accelerated by the emergence of recombinant polytropic or mink cell focus-forming (MCF) viruses. Susceptibility to infection by polytropic/MCF and also by closely related xenotropic MLV has been mapped to Rmc1 on mouse chromosome 1 (refs 5-7). To identify this gene, we introduced an expression cDNA library prepared from mouse NIH3T3 fibroblasts into nonpermissive hamster cells and screened these cells for acquired susceptibility to MCF viruses encoding beta-galactosidase and G418 resistance. From hamster cell clones identified in the screen, we recovered a mouse cDNA that maps to Rmc1 and confers MCF MLV infection when expressed in nonpermissive cell lines. It encodes a membrane protein related to Syg1p (suppressor of yeast G alpha deletion; ref. 8). The receptor-binding domain of the MCF MLV envelope protein binds specifically to Xenopus laevis oocytes that express mouse Syg1, suggesting it functions as a receptor that mediates virus entry. We also obtained the cDNA encoding human SYG1. When expressed in hamster cells, it establishes infectivity by MCF MLV as well as xenotropic MLV, which do not infect laboratory mice.     

Synthesis of 9-deoxo-4'-deoxy-6,9-epoxyerythromycin derivatives: novel and acid-stable motilides

In our quest toward the discovery of highly potent and acid-stable motilides, novel 4"-deoxy derivatives of 9-deoxo-6, 9-epoxyerythromycin were designed, synthesized, and evaluated for their gastrointestinal prokinetic activities. These compounds, in their 9R configuration, were more potent than their 6,9-enol ether homologues in inducing well-coordinated smooth muscle contractions in an in vitro rabbit duodenal assay: e.g., (9R), (8S)-9-deoxo-4"-deoxy-3'-N-desmethyl-3'-N-ethyl-6, 9-epoxyerythromycin A (10) and (9R), (8S)-9-deoxo-4"-deoxy-3'-N-desmethyl-3'-N-ethanol-6, 9-epoxyerythromycin A (15) had a pED50 of 8.54 and 8.11 compared to a pED50 of 7.22 for compound 2 (ABT-229). Reduction of the 6,9-enol ether, which was aimed at improving the acid stability, afforded the most stable motilides to date with t1/2 of 5.5 h for 10 and 15. Compounds 10 and 15 bind specifically to rabbit antral smooth muscle motilin receptors with pIC50 values of 8.52 and 8.70.     

SOME THERMODYNAMIC PROPERTIES OF Pd-In ALLOYS

1.IntroductionPdalloysareausefulsubjectforrelatingthermodynamicpropertieswithelectronicandelasticquantitiesofthecomponents.ThethermodynamicfunctionsofanumberofinterstitialandsubstitutionalPdalloysexhibitanalogouscharacteristicsandmaybeinterpretedinthesamemanner-Twoeffectswerediscussedtoaccountforthenon-idealproperties.An"elastic"effectisassociatedwiththelatticedistortionbroughtaboutbythedissolvedparticles.Theenergyofelasticstrainfieldsoftwoseparatesoluteatomsischangediftheparticlesenteradjace…