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Twelve cases of hepatocellular carcinoma treated by arterial embolization were followed with ultrasonography. Shrinkage of the tumor after the therapy was confirmed in all cases. Echo level reduction in the tumor occurred in 10 cases. High-level reverberation echoes with acoustic shadows emerged in seven cases; however, these echoes were not detected in any cases 3 weeks after the procedure. Echoes were considered either as the consequence of gas produced in the tumor or air trapped in the embolic substance. Ultrasonography, therefore, is an effective technique for the posttherapeutic evaluation of arterial embolization therapy for hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Photocatalytic TiO(2) powders impart ultraviolet light-induced self-cleaning and antibacterial functions when coated on outdoor building materials. For indoor applications, however, TiO(2) must be modified for visible-light and dark sensitivity. Here we report that the grafting of nanometer-sized Cu(x)O clusters onto TiO(2) generates an excellent risk-reduction material in indoor environments. X-ray absorption near-edge structure using synchrotron radiation and high-resolution transmission electron microscopic analyses revealed that Cu(x)O clusters were composed of Cu(I) and Cu(II) valence states. The Cu(II) species in the Cu(x)O clusters endow TiO(2) with efficient visible-light photooxidation of volatile organic compounds, whereas the Cu(I) species impart antimicrobial properties under dark conditions. By controlling the balance between Cu(I) and Cu(II) in Cu(x)O, efficient decomposition and antipathogenic activity were achieved in the hybrid Cu(x)O/TiO(2) nanocomposites.

Mutans streptococci are major etiological agents of dental caries, and several of their secreted products contribute to bacterial accumulation on teeth. Of these, Streptococcus mutans glucan binding protein B (GbpB) is a novel, immunologically dominant protein. Its biological function is unclear, although GbpB shares homology with a putative peptidoglycan hydrolase from S. agalactiae and S. pneumoniae, indicative of a role in murein biosynthesis. To determine the cellular function of GbpB, we used several approaches to inactivate the gene, analyze its expression, and identify interacting proteins. None of the transformants analyzed were true gbpB mutants, since they all contained both disrupted and wild-type gene copies, and expression of functional GbpB was always conserved. Thus, the inability to obtain viable gbpB null mutants supports the notion that gbpB is an essential gene. Northern blot and real-time PCR analyses suggested that induction of gbpB expression in response to stress was a strain-dependent phenomenon. Proteins that interacted with GbpB were identified in pull-down and coimmunoprecipitation assays, and these data suggest that GbpB interacts with ribosomal protein L7/L12, possibly as part of a protein complex involved in peptidoglycan synthesis and cell division.

Porphyromonas gingivalis has been implicated as an important pathogen in the development of adult periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. One potential virulence factor, hemagglutinin, may mediate bacteria attachment onto and penetration into host cells, as well as agglutinate and lyses erythrocytes to intake heme, an absolute requirement for growth. Toward the development of passive immunotherapy, the construction of a human type monoclonal antibody, which is capable of inhibiting the hemagglutinating ability, will be significant and important. The human mAbs, both exhibiting a high degree of specificity and affinity against the recombinant 130 kDa hemagglutinin domain protein have been prepared using XenoMouse technology. The constructed Xeno-mAbs, IgG2 subclass, significantly inhibited hemagglutination of P. gingivalis and its vesicles. The newly constructed Xeno-mAbs may prove to be useful for the development of passive immunization against periodontal diseases caused by P. gingivalis infection, pending the results of fertility study in disease mode.

Porphyromonas gingivalis, a gram-negative oral anaerobe, is strongly associated with adult periodontitis. The adherence of the organism to host epithelium signals changes in both cell types as bacteria initiate infection and colonization and epithelial cells rally their defenses. We hypothesized that the expression of a defined set of P. gingivalis genes would be consistently up-regulated during infection of HEp-2 human epithelial cells. P. gingivalis genome microarrays were used to compare the gene expression profiles of bacteria that adhered to HEp-2 cells and bacteria that were incubated alone. Genes whose expression was temporally up-regulated included those involved in the oxidative stress response and those encoding heat shock proteins that are essential to maintaining cell viability under adverse conditions. The results suggest that contact with epithelial cells induces in P. gingivalis stress-responsive pathways that promote the survival of the bacterium.

We used Porphyromonas gingivalis gene microarrays to compare the total gene contents of the virulent strain W83 and the avirulent type strain, ATCC 33277. Signal ratios and scatter plots indicated that the chromosomes were very similar, with approximately 93% of the predicted genes in common, while at least 7% of them showed very low or no signals in ATCC 33277. Verification of the array results by PCR indicated that several of the disparate genes were either absent from or variant in ATCC 33277. Divergent features included already reported insertion sequences and ragB, as well as additional hypothetical and functionally assigned genes. Several of the latter were organized in a putative operon in W83 and encoded enzymes involved in capsular polysaccharide synthesis. Another cluster was associated with two paralogous regions of the chromosome with a low G+C content, at 41%, compared to that of the whole genome, at 48%. These regions also contained conserved and species-specific hypothetical genes, transposons, insertion sequences, and integrases and were located adjacent to tRNA genes; thus, they had several characteristics of pathogenicity islands. While this global comparative analysis showed the close relationship between W83 and ATCC 33277, the clustering of genes that are present in W83 but divergent in or absent from ATCC 33277 is suggestive of chromosomal islands that may have been acquired by lateral gene transfer.

A simple and practical 6.8-cm-diameter (36.30-cm(2) cross-sectional-area) preparative disk gel electrophoresis device, based on the design of M. Hayakawa et al. (Anal. Biochem. 288 (2001) 168), in which the elution buffer is driven by an electroosmotic buffer flow through the membrane into the elution chamber from the anode chamber was constructed. We have found that the dialysis membranes employed provide suitable flow rates for the elution buffer, similar to those of an earlier 3.6-cm-diameter device, resulting in the prevention of excess eluate dilution. The efficiency of this device was demonstrated by the fractionation of a bovine serum albumin (BSA) Cohn V fraction into monomer, dimer, and oligomer components using nondenaturing polyacrylamide gel electrophoresis (native-PAGE). The maximum protein concentration of the eluate achieved was 133 mg/ml of BSA monomer, which required a dilution of the eluate for subsequent analytical PAGE performance. As a practical example, the two-dimensional fractionation of soluble dipeptidyl peptidase IV (sDPP IV) from 50 ml fetal bovine serum (3.20 g protein) per gel is presented. The sDPP IV enzyme protein was recovered in a relatively short time, utilizing a 6.5% T native-PAGE and subsequential sodium dodecyl sulfate-PAGE system. This device enhances the possibility of continuous electrophoretic fractionation of complex protein mixtures on a preparative scale., (Copyright 2003 Elsevier Science (USA))

Background: Porphyromonas gingivalis has been implicated as an important pathogen in the development of chronic periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. One potential virulence factor, hemagglutinin, may mediate bacteria attachment onto and penetration into host cells, as well as agglutinate and lyse erythrocytes to intake heme, an absolute requirement for growth. We previously cloned the gene encoding the 130 kDa hemagglutinin domain (130k HMGD) and identified its functional domain. The construction of a human monoclonal antibody that is capable of inhibiting the hemagglutinating ability is significant and important toward the development of passive immunotherapy., Methods: Human lymphocytes isolated from a donor, who had high antibody titer against the recombinant 130k HMGD (r130k HMGD), were immortalized by Epstein-Barr virus, and specific antibody-producing B cells were established by panning using the r130k HMGD., Results: The constructed HuMAb-HMGD1, IgG subclass, recognized the r130k HMGD as well as the 43 and 49 kDa major bands in P. gingivalis cells and vesicles. The HuMAb-HMGD1 significantly inhibited hemagglutinating activity of P. gingivalis vesicles in a dose-dependent manner. Furthermore, the HuMAb-HMGD1 recognized the synthetic peptide, EGSNEFAPVQNLTGSSVG, which contains the functional domain of 130k HMGD., Conclusion: The newly constructed HuMAb-HMGD1 may prove to be useful for the development of passive immunization against periodontal diseases caused by P. gingivalis infection, pending the results of fertility study in disease mode.

Porphyromonas gingivalis is a gram-negative anaerobic bacterial species implicated as an important pathogen in the development of adult periodontitis. Hemagglutinin may mediate the adsorption and invasion of bacteria into host cells. Furthermore, the hemagglutinin plays a role in the agglutinate and lyse erythrocytes intake of heme which is an absolute requirement for this bacterial growth. We previously cloned the gene encoding the 130-kDa hemagglutinin protein domain (130-kDa HMGD) and identified the functional motifs of agglutination of erythrocytes. Bacterial cell attachment to erythrocytes is an important initial step in the expression of hemolytic activity. In this study, we highly purified recombinant r130-kDa HMGD and prepared the specific antiserum. Further, the effect of the antibody on the hemolytic activity of P. gingivalis cells was examined. The polyclonal antibody recognized 43,49-kDa major bands in P. gingivalis cells and r130-kDa HMGD, and significantly inhibited the hemagglutinating and hemolytic activities of P. gingivalis cells. The findings suggest that the antibody may be useful in the development of the passive immunization against periodontal diseases caused by P. gingivalis infection.

Porphyromonas gingivalis has been implicated as an important pathogen in the development of adult periodontitis. This bacterium possesses hemagglutinating and hemolytic activities to attach and lyse erythrocytes. Hemolysis by this oral pathogen functions to provide heme-containing molecules for growth in the periodontal pocket. We previously constructed a monoclonal antibody using P. gingivalis vesicles as the immunogen, designated as MAb-Pg-vc, which inhibited vesicle-associated hemagglutinating activity. Furthermore, we cloned the gene encoding 130-kDa hemagglutinin (130-kDa HAG) and identified its functional motif for attachment to erythrocytes. Generally, bacterial cell attachment to erythrocytes is an important initial step for expressing hemolysis activity. In the present study, we examined the effect of MAb-Pg-vc on the hemolytic activity of P. gingivalis cells. The MAb-Pg-vc significantly inhibited the hemolytic activity and, further, this inhibitory activity was reduced by the synthetic peptide of the 130-kDa HAG functional motif.

This paper describes an improved electroosmotic elution system for preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) based on the epochal idea of H. V. Tan et al. (Nucleic Acids Res. 1988, 16, 1921-1930). In this elution system, a semipermeable membrane, mounted under the gel terminal end, works as the elution pump as well as the partition of the elution chamber. We refer to this system as the "electroosmotic medium pump system." Operation of the constructed apparatus (3.6 cm i.d. disk gel column) and resolution of the protein bands were examined by separation of the model protein mixture (bovine serum albumin (BSA), ovalbumin, bovine carbonic anhydrase, soybean trypsin inhibitor) and purification of the membrane protein, dipeptidyl peptidase IV (DPP IV). The Spectra/Por 7 dialysis membrane provided a better flow profile for the elution buffer. The four model proteins of the protein mixture were able to be completely separated from each other and recovered without dilution. The maximum protein concentration of eluate achieved was 93 mg/ml, when applying a single component, BSA fraction V, as a sample. Furthermore, the multifunctional ectoenzyme, DPP IV, was purified in a single step., (Copyright 2001 Academic Press.)

Direct coronal CT was performed on 6 cases of urinary bladder tumor in which conventional axial transverse CT failed to depict the relationship between the lesion and bladder wall. GE CT/T 8800 was used, and the bladder was scanned with patients crouched on the table opposite the gantry. The relationship between the tumor and bladder wall as well as the surrounding organs was visualized in 5 of 6 cases examined. THe CT diagnosis and histological findings coincided in 4 of these 5. Direct coronal CT was useful for diagnostic determination of clinical stage for tumors occurring in the apical or basal region of the urinary bladder.

The hepatic arteries of 122 patients were analysed on angiography to identify the left medial segment of the liver. Left medial arterial branches were classified into three types: type I arising from the left hepatic artery on the umbilical portion of the portal vein; type II arising from proximal portion of left hepatic artery before reaching the umbilical portion of the portal vein; type III arising from right hepatic artery. Incidence of each type is 37.2%, 35.8% and 27.0%, respectively. The artery frequently kinks at the right side of the umbilical portion of the portal vein and a total of incidence is 68% and that of each type is 23.5%, 89.8% and 100%, respectively. We call this characteristic kinking point of the left medial arterial branches, the "M-point".