Jutaro Tadano

Protein-bound polysaccharide PSK inhibits tumor invasiveness by down-regulation of TGF-β1 and MMPs

Transforming growth factor β1 (TGF-β1) and matrix metalloproteinases (MMPs) produced by tumor cells play important roles in tumor invasion. PSK, a protein-bound polysaccharide, is widely used in Japan as an immunopotentiating biological response modifier for cancer patients. In this study, we focused on the effects of PSK on invasiveness, TGF-β1 production, and MMPs expression in two human tumor cell lines, pancreatic cancer cell line (NOR-P1) and gastric cancer cell line (MK-1P3). PSK significantly decreased the invasiveness of both cell lines through Matrigel-coated filters but did not affect cell viability, proliferation, or adhesion. Decreased invasion was associated with the inhibition of TGF-β1, MMP-2, and MMP-9 at both mRNA and protein levels as assessed by reverse transcriptase-polymerase chain reaction, gelatin zymography, and enzyme-linked immunosorbent assay. Antibody against TGF-β1 neutralized the MMP activities of both cell lines. PSK also suppressed the expression of urokinase plasminogen activator (uPA) and uPA receptor but did not change plasminogen activator inhibitor-1 (PAI-1) expression. Western blot analysis showed that PSK reduced uPA protein expression but not PAI-1 expression in the both cell lines. These results indicate that PSK suppresses tumor cell invasiveness through down-regulation of several invasion-related factors including TGF-β1, uPA, MMP-2, and MMP-9.

Screening of organophosphorus pesticides using liquid chromatography-atmospheric pressure chemical ionization mass spectrometry

Screening and identification of organophosphorus pesticides in blood from patients suffering from acute agricultural chemical toxicity were established by a liquid chromatography-atmospheric pressure chemical ionization mass spectrometric method. To determine 21 pesticides, it was necessary to monitor both positive and negative ions. This method could easily screen for 21 organophosphorus pesticides in less than 30 min. By comparison with a gas chromatographic-mass spectrometric method, the chemicals indicated a similar extent of specificity and within equivalent detection limits, thus satisfying clinical requirements completely.

Simple, rapid and simultaneous measurement of eight different types of carbamate pesticides in serum using liquid chromatography—atmospheric pressure chemical ionization mass spectrometry

We have developed a method for simultaneous analysis of methylcarbamate pesticides in serum with an acute pesticide intoxication. This is performed by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry. Rapid detection of eight types of methylcarbamate pesticide can be achieved with this method, it only requires an extremely simple pre-treatment of the sample. The specificity of this method is equal to that of gas chromatography-mass spectrometry, and it satisfies the clinical requirements for detection sensitivity and specificity. Although some problems with this analytical method remain to be solved, we consider it to be superior to any other analytical method previously reported.

Necrotizing fasciitis caused by Vibrio vulnificus differs from that caused by streptococcal infection

We reviewed the clinical record of all patients admitted to Saga Medical School Hospital during the most recent 10 years and found that 17 (0.03%) were diagnosed as having necrotizing fasciitis. Bacteriological examination demonstrated that Vibrio vulnificus was the pathogen responsible in five patients (29%). The disease caused by V. vulnificus occurred in the warmer half of the year. All of the patients had underlying chronic liver dysfunction, and three of them had previously consumed raw seafood. In these patients, the predominant skin lesions were oedema and subcutaneous bleeding, such as ecchymosis and purpura, while superficial necrosis was not recognized. Three patients died of systemic complications. By contrast, all of the five patients with necrotizing fasciitis caused by Streptococcus pyogenes had the disorder in winter, and only one of them had chronic liver dysfunction. In skin lesions, subcutaneous bleeding was rare but necrosis was seen often. Despite the high incidence of systemic complications, no patients with streptococcal necrotizing fasciitis died. These findings suggest that the clinical features of necrotizing fasciitis caused by V. vulnificus are different from those of necrotizing fasciitis caused by classical pathogens, and that the two should be differentiated as early as possible to improve the prognosis.

Characterization of humoral and cellular immunity in the central nervous system of HAM/TSP.

In HTLV-I-associated myelopathy or tropical spastic paraparesis (HAM/TSP) immunopathological processes in the central nervous system (CNS) have not been clarified. We compared the humoral and cellular immunity within the CNS and in the systemic circulation of 24 patients with HAM/TSP (8 men and 16 women) to 6 asymptomatic HTLV-I carriers, 7 patients with active multiple sclerosis, 6 patients with acute viral encephalitis, and 39 patients with other non-inflammatory neurological diseases. Significant differences were observed between the HAM/TSP patients and one or more of the control groups: HAM/TSP cerebrospinal fluids (CSF) exhibited higher levels of IgG, IgG index, de novo IgG synthesis rate, and beta 2-microglobulin, and also a predominance of CD8+ cells that expressed CD11a and CD45RO but lacked CD28 antigens. Results in the 6 patients with acute viral encephalitis suggested that the CD8+ population in the CSF which is positive for CD28 and CD45RO is important for the elimination of virus from infected CNS tissues. Therefore, potentially cytotoxic T cells of a unique CD8+CD11a+CD45RO+CD28- phenotype may play a key role in the CNS pathogenesis of HAM/TSP.

Increased proliferation of a human breast carcinoma cell line by recombinant interleukin-2

Two adenocarcinoma cell lines, Breast M25-SF and Breast M, were established from tumor tissue resected surgically from a patient with breast cancer. One, Breast M25-SF, expresses interleukin-2 receptor (IL-2R) on the cell surface and the other, Breast M, does not. The effects of recombinant inteleukin-2 (rIL-2) on the proliferation of these cell lines were investigated. The growth of Breast M25-SF was significantly promoted by rIL-2 ranging from 1,25 U/ml to 640 U/ml. Anti-CD25 (Tac) antibody, significantly blocked the growth enhancement of Breast M25-SF by rIL-2. Breast M, however, did not respond to rIL-2. To confirm more directly the promotion of Breast M25-SF growth by rIL-2, cloning of IL-2 responders from parent Breast M25-SF cells was carried out by limiting dilution without feeder cells in 96-well microplates. No colony formation was found in 24 wells without rIL-2. Eleven, 13 and 6 clones were established from groups of 24 wells containing rIL-2 at 200, 20 and 2 U/ml respectively. All of the clones expressed IL-2R and respond to rIL-2. By using a sensitive polymerase chain reaction technique, we demonstrated that Breast M25-SF but not Breast M expressed IL-2 mRNA, and IL-2 secretion from Breast M25-SF but not Breast M was also confirmed by radioimmunoassay. These findings suggest a role for IL-2 in autocrine support of Breast M25-SF growth. IL-2 may play an important role in the growth control of breast carcinoma cells.

A Factor Found in Aged Tungstate Solution Enhanced the Antibacterial Effect of β‐Lactams on Methicillin‐Resistant Staphylococcus aureus

We have found a factor (Factor T) in aged mixtures of tungstate and phosphate which greatly enhances the antibacterial effects of β‐lactams on both inducible and constitutive methicillin‐resistant Staphylococcus aureus, but not on methicillin‐susceptible S. aureus. Factor T alone did not strongly inhibit bacterial growth. There was no synergism of Factor T with other classes of antibiotics, nor with other groups of bacteria, and it reduced the efficacy of aminoglycosides and tetracycline. Upon preparation of Factor T, acidifying and heating the mixture of tungstate and phosphate resulted in a high yield and reproducibility, and no enhancing effect was observed when other anions such as sulfate or molybdate were used instead. Factor T is heat‐ and acid‐stable but labile to alkalization, and is probably a complex of phosphate and tungstate.

Pulmonary Colonization by Chrysosporium zonatum Associated with Allergic Inflammation in an Immunocompetent Subject

ABSTRACT We report a case of noninvasive pulmonary disease due to Chrysosporium zonatum in an immunocompetent male. The fungus colonized an existing tuberculous cavity and was isolated from transbronchial lavage fluid and from a percutaneous aspiration specimen. The disease was accompanied by the unusual feature of an allergic reaction. The fungus ball was successfully treated by intracavitary administration of amphotericin B. C. zonatum is the anamorph of the heterothallic ascomycete Uncinocarpus orissi, and the identity of the case isolate was verified by formation of ascospores in mating tests with reference isolates.

Possible mechanism of action of β-lactam-enhancing factor on methicillin-resistant Staphylococcus aureus

We have recently found a factor (Factor T) in aged mixtures of tungstate and phosphate which greatly enhances the antibacterial effects of β‐lactams on methicillin‐resistant strains of staphylococcal species such as methicillin‐resistant Staphylococcus aureus (MRSA), but shows only weak effects on methicillin‐susceptible S. aureus and bacterial strains other than staphylococci. Factor T alone did not strongly inhibit cell metabolism and bacterial growth unless an excess amount was added. When Factor T was added to the culture medium beforehand, the growth of MRSA cells was rapidly suppressed just after addition of oxacillin (MPIPC). However, the growth of the cells was inhibited gradually when these two reagents were added in reverse order. For full expression of the enhancing effect, it seemed necessary for cells of MRSA strains to be incubated with Factor T for at least 2–3 hr. When the cells were washed after being sensitized by incubating them for 5 hr with Factor T, it took approximately 1 hr for the cells to recover their resistance to MPIPC. Factor T reduced the amount of penicillin‐binding protein‐2′ (PBP 2′), and thus sensitized the MRSA strains to β‐lactams.

Inhibition of tumor cell growth by a human B-cell line

An Adenocarcinoma cell line (Breast-M) and an Epstein-Barr virus (EBV)-infected B-cell line (Hairy-BM) were established from breast tumor tissue. The Hairy-BM was CD20+, CD25 (Tac)+ and surface immunoglobulin (sIg)+. Hairy-BM suppressed the in vitro proliferation of Breast-M in a time and a dose-dependent manner. The suppression was also found in 5 different human tumor targets showing tumor-Hairy-BM binding, but not; in 2 murine tumor targets showing no significant tumor-Hairy-BM binding. Lytic activity of Hairy-BM was found only against Breast-M.