A seroepidemiologic study of hepatitis B virus infection among barbers in Huangshi City, Hubei, China

Between March and August 1986 in Huangshi City, serum samples were collected from 316 apparently healthy barbers as a study group, as well as from 361 healthy employees of department stores as a control group. They were tested for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs) and antibody to hepatitis B core antigen (anti-HBc) by enzyme-linked immunoadsorbent assays. Barbers showed a prevalence higher than that in controls for HBsAg (16.8 vs. 9.2%, P less than 0.01), anti-HBs (67.1 vs. 45.9%, P less than 0.001), and anti-HBc (39.2 vs. 21.2%, P less than 0.001). The prevalence of at least one marker of hepatitis B virus (HBV) infection was significantly higher in barbers than in controls (86.1 vs. 61.7%, P less than 0.001). Although the socioeconomic status and education level did not correlate with the frequency of HBV markers, the prevalence of HBsAg increased in parallel with the duration of practice. Because of their high risk for HBV infection, barbers need to be screened for markers of HBV infection on a routine basis, and are prime candidates for immunoprophylaxis with hepatitis B vaccine.

Characterization of a potent platelet aggregation inhibitor from Agkistrodon rhodostoma snake venom

By means of CM-Sephadex C-50 column chromatography and gel filtration on Sephadex G-75 and G-50 columns, a potent platelet aggregation inhibitor was purified and characterized. It was a glycoprotein with a molecular weight of 31,000. It was devoid of phospholipase A, ADPase, esterase and fibrino(geno)lytic activities. It inhibited dose-dependently the aggregation of washed platelets induced by collagen, thrombin, sodium arachidonate, platelet activating factor and ionophore A23187 with a similar IC50 (5-10 micrograms/ml). It was also active in platelet-rich plasma, with an IC50 of 10-15 micrograms/ml. The venom inhibitor reduced the elasticity of whole blood clot and inhibited the thrombin-induced clot retraction of platelet-rich plasma. These activities were related to its inhibitory activity on platelet aggregation rather than blood coagulation. The venom inhibitor had various effects on [14C]serotonin release stimulated by aggregation agonists. It had no effect on thromboxane B2 formation of platelets stimulated by sodium arachidonate, collagen and ionophore A23187. The presence of this venom inhibitor prior to the initiation of aggregation was a prerequisite for the maintenance of its maximal activity. It showed a similar inhibitory effect on collagen or thrombin-induced aggregation even when it was added after the platelets had undergone the shape change. High fibrinogen levels partially antagonized its activity. The venom inhibitor completely inhibited the fibrinogen-induced aggregation of alpha-chymotrypsin-treated platelets. It is concluded that this venom inhibitor interferes with the interaction of fibrinogen with fibrinogen receptors, leading to inhibition of aggregation.

Ultrastructure and function of oviduct-uterine junction in Ascaris suum (Nematoda)

Cells comprising the oviduct-uterine junction of the female reproductive tract in Ascaris suum were shown to have a distinctive ultrastructure. The free luminal surface of each epithelial cell was bordered by an electron-dense layer that measured 90 to 120 nm in thickness and could be removed by treatment with pronase. Numerous membrane-bound, filament-containing bodies were present in the cytoplasm near the apical margin. These filaments, measuring 6.5 nm in diameter, coalesce (or condense) to form a larger coiled, or homogeneous, electron-dense substance. These membrane-bound, filament-containing bodies often fused with the plasma membrane and released their contents into the lumen. In other instances, the filamentous arrangements were not membrane bound and remained within the cytoplasm where they formed electron-dense masses adjacent to the plasma membrane. Basal infoldings suggestive of water or ion transport occurred in each cell. Externally, the cells were bordered by a basement lamina and muscle cells.

The mesothelial keratins: a new family of cytoskeletal proteins identified in cultured mesothelial cells and nonkeratinizing epithelia

The cytoskeletal proteins of cultured normal human mesothelial cells were found to consist of six major components, including actin, vimentin, the 40 kd keratin and the 44, 52 and 55 kd proteins, plus a minor 46 kd protein. Two-dimensional gel electrophoresis, peptide mapping and immunoprecipitation tests showed that the 40-55 kd mesothelial proteins are a family of keratins distinct in size, charge or peptide map from the "epidermal keratins" synthesized by cultured keratinocytes. Unique combinations of keratins from the epidermal and mesothelial keratin families were found to be synthesized by cultured bladder, esophageal, conjunctival, mammary, exocervical and ovarian surface epithelial cells. Mesothelial cells were the only epithelial cell type that synthesized vimentin at more than trace levels. We have also found that many carcinoma cell lines express keratins different from those of their cell type of origin.

The mesothelial keratins: a new family of cytoskeletal proteins identified in cultured mesothelial cells and nonkeratinizing epithelia

The cytoskeletal proteins of cultured normal human mesothelial cells were found to consist of six major components, including actin, vimentin, the 40 kd keratin and the 44, 52 and 55 kd proteins, plus a minor 46 kd protein. Two-dimensional gel electrophoresis, peptide mapping and immunoprecipitation tests showed that the 40-55 kd mesothelial proteins are a family of keratins distinct in size, charge or peptide map from the "epidermal keratins" synthesized by cultured keratinocytes. Unique combinations of keratins from the epidermal and mesothelial keratin families were found to be synthesized by cultured bladder, esophageal, conjunctival, mammary, exocervical and ovarian surface epithelial cells. Mesothelial cells were the only epithelial cell type that synthesized vimentin at more than trace levels. We have also found that many carcinoma cell lines express keratins different from those of their cell type of origin.

Immunological studies of the relationship between the antigenic change of Ascaris oocytes and the junctional fluid of the fertilization chamber

Antigenic change on the surface of immature oocytes of Ascaris occurred during passage through the oviduct. Using immunodiffusion and immunoelectrophoretic techniques we examined the possible relationship between the antigenic change of immature oocytes and the junctional fluid (JF) which is present in the fertilization chamber. From the immunodiffusion it was found that the anti-immature oocyte serum (A-I serum) had more immunoprecipitation arcs than did the anti-mature oocyte serum (A-M serum) when reacted against the junctional fluid. This indicated that A-I serum contained more immunoglobulins that reacted with junctional fluid than did the A-M serum. This result was substantiated by using immunoelectrophoretic analysis and two dimension crossed immunoelectrophoresis. Our results suggest that during the migration toward the oviduct-uterine junction the immature oocytes might shed surface proteins into the luminal fluid. Alternatively, the membrane surface of mature oocytes may be altered by the interaction with the substances present in the junctional fluid.

Ascaris oocytes: ultrastructural and immunocytochemical changes during passage through the oviduct

Slender, bipolar, immature, Ascaris suum oocytes assume a smooth, spherical configuration as they traverse the oviduct. The present investigation was conducted to determine if this morphological alteration might be accompanied by changes in surface membranes. Immunocytochemical studies were conducted utilizing (1) fluorescein-labeled, sheep, anti-rabbit IgG, (2) Sternberger's unlabeled, antibody-enzyme technique, (3) ferritin-labeled, sheep, anti-rabbit IgG, and (4) an immunobead, labeled-antibody technique. These procedures clearly demonstrated that the surface of both immature and mature oocytes possessed different specific antigens. It is assumed that this acquisition of new antigens (or the loss of older ones) by the mature oocyte is somehow related to a conditioning phenomenon which prepares the oocyte for fertilization.

Inhibition of separated forms of phosphodiesterases from pig coronary arteries by uracils and by 7-substituted derivatives of 1-methyl-3-isobutylxanthine

A series of 7-substituted 1-methyl-3-isobutylxanthines was designed in an attempt to increade the specificity of the 1-methyl-3-isobutylxanthine (MIX) structure for one of the two cyclic nucleotide phosphodiesterase peaks isolated by DEAE-cellulose chromatography of the soluble fraction of the intima + media layer of pig coronary arteries. A series of 1,3-dialkyluracils was of low potency as inhibitors of either peak I or peak II. The 7-substituted xanthines were prepared by alkylation of MIX with the corresponding alkyl or aralkyl halide in DMF containing K2CO3. These compounds were, in general, much less potent inhibitors of peak II activity than was MIX, but some of them retained the potency of MIX as inhibitors of peak I and, therefore, were relatively specific for inhibition of peak I. 7-Bzl-MIX was the most selective compound tested; it was a potent inhibitor of peak I activity but was much less effective as an inhibitor of peak II activity. Substitution of either electron-withdrawing (nitro) or electron-donating (methoxy) groups on the 7-benzyl moiety reduced the effectiveness of the 7-benzyl compounds as inhibitors of peak I. Chlorobenzyl substitution increased the potency slightly over the benzyl but not the selectivity between peaks.