Errors reading the Ishihara pseudoisochromatic plates made by observers with normal colour vision

Background: Ishihara pseudoisochromatic plates are one of the best screening tools for red‐green colour vision deficiencies. Although a majority of persons with normal colour vision read all plates correctly, a significant proportion makes mistakes. The purpose of this study was to obtain results for normal trichromats reading the Ishihara plates and analyse the misreading responses to seek clinical implications. Methods: A sample of 249 (161 female) was tested with the Ishihara pseudoisochromatic plates. The number and nature of errors were recorded and typical errors, those that observers with abnormal colour vision were expected to make, were distinguished from other kinds of error. Results: Out of 249 normal trichromats, 111 individuals (45 per cent) misread at least one plate. Females made up to six total errors and males up to five total errors. When only typical errors were counted, all the normal trichromats made two or fewer errors. There was no significant gender difference for either total or typical errors. Conclusion: It is suggested that clinicians count only typical errors when administering the Ishihara test. Using a criterion of no more than two typical errors for a diagnosis of normal colour vision could improve the specificity and sensitivity of the test.     

Role of protease activated receptor-2 in lymph node metastasis of uterine cervical cancers

Background  

Protease activated receptor-2 (PAR-2) has been implicated in cellular proliferation, invasion and metastasis in various tumors. Lymph node metastasis is an important patient prognostic factor for uterine cervical cancers. This prompted us to study the role of PAR-2 in lymph node metastasis of uterine cervical cancers.     

Persistent T-cell mixed chimerism in a case of malignant lymphoma after nonmyeloablative allogeneic peripheral blood stem cell transplantation

We describe a 51-year-old woman with recurrent follicular lymphoma from the age of 47 despite chemo-radio therapy, who subsequently underwent nonmyeloablative stem cell transplantation with conditioning consisting of fludarabine and low-dose total body irradiation (2 Gy). Myelosuppression was very mild, so the patient required no transfusions. Chimerism analysis from peripheral blood showed that T-cell mixed chimerism continued over 12 months after stem cell transplantation (the percentage of recipient T-cells was approximately 20%). Despite this, the lymphadenopathy disappeared, and the patient developed grade II acute GVHD (graft versus host disease). It has been considered that the establishment of full donor chimerism is required to induce GVHD and GVM (graft versus malignancy) effects. In this case, however, an allo-response was observed despite the persistence of T-cell mixed chimerism.     

Successful open stent grafting of a right aortic arch and a descending aortic aneurysm originating from a Kommerell's diverticulum: report of a case

The case of a 43-year-old man found to have an aneurysm developing from a Kommerell's diverticulum at the origin of an aberrant retroesophageal left subclavian artery is reported herein. The aneurysm was treated by the open stent grafting technique and complete revascularization was achieved. Received: February 8, 2001 / Accepted: September 11, 2001     

Mitogen-activated protein kinase inhibitor,PD98059, inhibits rat retinal pigment epithelial cell replication by cell cycle arrest

PURPOSE: To investigate the effect of PD98059, a mitogen-activated protein kinase (MAPK) inhibitor, on the replication of rat cultured retinal pigment epithelial (RPE) cells. METHODS: Growth-phase rat RPE cells were exposed to various concentrations of PD98059 in serum-free F12 medium containing 0.1% dimethyl sulfoxide. Cell proliferation was assessed by cell counts using a hemocytometer. Cell viability was tested by CellTiter 96 AQueous Non-Radioactive Cell Proliferation Assay at 24 hours after PD98059 application. Hoechst 33552 and propidium iodide staining were used to assess nuclear morphology. Immunostaining with Ki67 antibody was used for cell cycle analysis because the staining patterns produced on cells are characteristic depending on their position within the cell cycle. RESULTS: PD98059 inhibited cellular proliferation of cultured rat RPE cells in a dose-dependent manner but did not induce cell death. Twenty-four hours after the application of PD98059, cultured RPE cells were not immunopositive for Ki67, indicating that their cell cycle was arrested in the G0/G1 phase. CONCLUSION: These results demonstrated that MAPK inhibition arrested cell cycle progression of rat cultured RPE cells at the G0/G1 phase. The pharmacological induction of cell cycle arrest could be a new approach to inhibit cellular proliferation in such conditions as proliferative vitreoretinopathy.     

Rapid bactericidal activities of carbapenems against Pseudomonas aeruginosa in simulating human plasma concentrations

The rapid bactericidal activities of panipenem (PAPM), imipenem (IPM), and meropenem (MEPM) against Pseudomonas aeruginosa were investigated by using in vitro pharmacodynamic model simulating the human plasma concentrations after intravenous drip infusion at 500 mg for 0.5 hours. Against P. aeruginosa PAO1, PAPM and IPM showed rapider reduction in viable cell counts than MEPM at 0.5 hours after exposure. All drugs showed more than 3 log10 reduction in viable cell counts at 2 hours after exposure and bacterial regrowth was not observed throughout 6 hours. The initial bactericidal activities of the drugs against 4 clinical isolates within 1 hour after exposure were also investigated by the same method. Against P. aeruginosa strain 12,475, the 3 drugs showed similar initial bactericidal activity but PAPM and IPM showed stronger initial bactericidal activity than MEPM against the other strains as did against P. aeruginosa PAO1. The morphological change of a strain 12,489, for which the initial bactericidal activities were different largely, after 0.5 hours exposure to simulated drug-concentrations was investigated by scanning electron microscope. PAPM and IPM induced morphological changes in most of the cells and cell lysis and bulge formation. On the other hand, MEPM induced changes of the surface structure of cells and slightly elongated cells, but not cell lysis.     

Helicobacter pylori may survive ampicillin treatment in the remnant stomach

Helicobacter pylori (H. pylori) is a Gram-negative curved rod-like or spiral bacterium that chronically infects the human gastric mucosa, and is a major risk factor for gastritis, gastric and duodenal ulcer and adenocarcinoma of the stomach. After partial gastrectomy, some patients may have persistent H. pylori infection for five years or more. In this study, we detected three bacteria, i.e., Klebsiella pneumoniae, Enterobacter aerogenes, and Escherichia coli, in the gastric juice of patients with a remnant stomach. Some of these bacteria produced beta-lactamase. These findings are potentially important since such bacteria could provide H. pylori with the chance to acquire drug resistance and to transfer drug resistance genes. This could be one reason why H. pylori is difficult to eradicate in the remnant stomach.     

Comparison of the efficiency and safety of non-viral vector-mediated gene transfer into a wide range of human cells

Non-viral gene transfer into a wide range of human cells was examined in order to clarify the factors that affect the efficiency and safety of non-viral vectors and to optimize the conditions so that high efficiency and low toxicity could be achieved. Six non-viral vectors (Lipofectin, LipofectAMINE PLUS, SuperFect, Effectene, DMRIE-C and DOTAP) were used to transfect a mammalian expression plasmid pCMVbeta into 16 types of human primary cells and cultured cell lines. Transfection efficiency was quantified using a galactosidase assay. Cytotoxic effects were measured by lactate dehydrogenase (LDH) assay and WST-8 assay. In serum-free conditions, LipofectAMINE PLUS, Effectene and SuperFect, on average, transfected DNA more successfully than Lipofectin, DMRIE-C, and DOTAP, although the levels of gene expression with these vectors varied remarkably in different cells. The most effective vector also differed depending on the cell type. Serum was found to inhibit gene transfer and reduce the cytotoxicity of all of these vectors except Effectene. The efficiency and toxicity of the non-viral vectors used depended on the type of vector, the DNA/vector ratio, the type of cell, and the presence of serum. These results provided useful information for the optimization of transfer conditions of these non-viral vectors.     

Sulfation of environmental estrogens by cytosolic human sulfotransferases

It is known that in humans taking soy food, the phytoestrogens, daidzein (DZ) and genistein (GS), exist as sulfates and glucuronides in the plasma and are excreted as conjugates in urine. To investigate which human sulfotransferase (SULT) isoforms participate in the sulfation of these phytoestrogens, the four major cytosolic SULTs, SULT1A1, SULT1A3, SULT1E1, and SULT2A1, occurring in the human liver were bacterially expressed as His-tagged proteins and chromatographically purified to homogeneity in the presence of Tween 20 and glycerol as highly efficient agents for stabilizing the recombinant enzymes. All the SULTs showed sulfating activity toward both DZ and GS. However, k(cat)/K(m) values observed indicated that these phytoestrogens were sulfated predominantly by SULT1A1 and SULT1E1 with K(m) values of 0.3 and 0.7 microM for GS and 1.9 and 3.4 microM for DZ, respectively. DZ and GS strongly inhibited the sulfation of the endogenous substrate, beta-estradiol, by SULT1E1 in a non-competitive manner with K(i) values of 14 and 7 microM, respectively, suggesting that these phytoestrogens might affect tissue levels of beta-estradiol in the human. The phenolic endocrine-disrupting chemicals, bisphenol A (BPA), 4-n-nonylphenol (NP), and 4-t-octylphenol (t-OP), were used as substrates to investigate the possible participation of human SULTs in their metabolism for excretion. High k(cat)/K(m) values were observed for the sulfation of BPA by SULT1A1, NP by SULT1A1 and SULT1E1, and t-OP by SULT1E1 and SULT2A1.     

Urokinase-type plasminogen activator is activated in stratum corneum after barrier disruption

The plasminogen/plasmin system in epidermis is thought to be the major protease involved in the delay of barrier recovery. However, little is known about the mechanism through which this system is activated. In order to clarify this mechanism, we first determined the distribution of proteolytic activity by using in situ zymography. As a result, plasminogen-activator activity was found to be present in the stratum corneum (SC) after barrier disruption. Next, SC subjected to repeated barrier disruption was collected to identify the protease. The protease was identified as urokinase-type plasminogen activator, because flybrinolytic activity of the collected SC was abolished by addition of anti-urokinase antibody. Urokinase activation in SC was confirmed by means of an in vitro assay, in which the precursor of urokinase (pro-uPA) became active after incubation with the insoluble component of SC homogenate. These findings indicated that urokinase-type plasminogen activator is activated in SC after barrier disruption and this activation might trigger the plasminogen/plasmin system in the epidermis.