A new type of mitogenic factor produced by Streptococcus pyogenes

A new type of mitogenic factor (protein) was purified from the culture supernatant of a strain of Streptococcus pyogenes by SP-Sephadex C-25 column chromatography, preparative isoelectric focusing and reversed-phase high-performance liquid chromatography. The purified factor, showing marked mitogenic activity in rabbit peripheral blood lymphocytes, gave a single-band staining for protein on SDS-PAGE. The molecular weight of the purified mitogenic factor was determined to be 25,370, which was different from those calculated from reported amino acid sequences deduced from 4 different nucleotide sequences of 3 kinds of streptococcal pyrogenic exotoxins (two SPEAs, SPEB and SPEC). The amino acid sequence of the N-terminal region of the purified mitogenic factor was determined to be Gln-Thr-Gln-Val-Ser-Asn-Asp-Val-Val-Leu-Asn-Asp-Gly-Ala-Ser-Lys-Tyr-Leu- Asn-Glu - Ala-, which was also different from the reported N-terminal sequences deduced from the 4 different nucleotide sequences. These data indicate that this mitogenic factor is distinct from the already described streptococcal pyrogenic exotoxins.

Effect of methotrexate treatment on the onset of autoimmune kidney disease in lupus mice

In the present study, we examined the effects of methotrexate (MTX) on the development of autoimmune kidney disease in three kinds of autoimmune prone mice, NZB/NZW F1 (BWF1) mice, MRL/Mp-lpr/lpr (MRL/lpr) mice and NZW/BXSB F1 (WBF1) mice. The results showed that MTX delayed the appearance of proteinuria and prolonged survival of both BWF1 and MRL/lpr mice and inhibited the elevation of blood urea nitrogen (BUN) levels which accompanies the development of lupus nephritis. However, MTX treatment did not affect these in WBF1 mice. Furthermore, MTX could not suppress immunoglobulin G (IgG) class anti-deoxyribonucleic acid (DNA) and anti-trinitrophenol (TNP) antibody production in any variety of mice. These suggest that the therapeutic effect of MTX on BWF1 and MRL/lpr mice does not result in the suppression of IgG autoantibody production.

Clinicopathologic study of alcohol-like liver disease in non-alcoholics; non-alcoholic steatohepatitis and fibrosis

Alcohol-like liver injury (ALLI) in non-alcoholics has not been elucidated in Japan. The present study attempted to characterize the clinicopathologic features of ALLI in routine liver biopsies. ALLI was found in 1% of 561 biopsy cases obtained from 1988 to May, 1991 at Kanazawa University Hospital. Laboratory data characteristically showed only a mild to moderate degree of dysfunction, and none of the cases exhibited jaundice. Hepatic histology showed a mild to moderate degree of perivenular, pericellular and/or portal stellate fibrosis with a varying degree of fatty change and inflammatory cell infiltration. Portal stellate fibrosis with a varying degree of cell infiltration was more severe than the centrilobular or pericellular fibrosis in all cases. Intralobular inflammatory cell infiltration was associated with spotty or single hepatocyte necrosis, but extensive hepatocyte necrosis was not observed. Neutrophil infiltration was absent or minimal, and lymphocytes predominated in all cases. Mallory bodies were rare and were found in a few hepatocytes of only one of the 7 cases. The above histologic findings in ALLI were very similar to those seen in liver disease in Japanese alcoholics, and were somewhat different from ALLI reported in Western countries. In cases in which hepatic fibrosis, characterized by pericellular, perivenular or portal stellate fibrosis dominated without apparent hepatic necrosis and inflammation, the term "non-alcoholic steatofibrosis" is more suitable to depict its liver histology, being very similar to the alcoholic fibrosis frequently seen in Japanese alcoholics.

Ligand binding kinetics of substance P and neurokinin A receptors stably expressed in Chinese hamster ovary cells and evidence for differential stimulation of inositol 1,4,5-trisphosphate and cyclic AMP second messenger responses

Stably transfected Chinese hamster ovary cells expressing either the substance P receptor or neurokinin A receptor were constructed, isolated, and characterized. Equilibrium ligand binding studies performed on whole cells demonstrated that cell lines expressing either of these receptors contained a single class of high-affinity binding sites with an apparent KD of 0.16 nM for the substance P receptor and an apparent KD of 2.1 nM for the neurokinin A receptor. The higher affinity of substance P for its receptor was accounted for by both a greater association rate constant and a lesser dissociation rate constant. The time course and extent of ligand-stimulated inositol 1,4,5-trisphosphate mass increases in both cell lines were similar and displayed rapid and transient kinetics. Ligand-stimulated cyclic AMP accumulation was also apparent in the cell lines, although the time course and magnitude of the responses were substantially different, with the neurokinin A receptor mediating a greater and more prolonged response. These studies establish the presence of functional substance P receptors and neurokinin A receptors in the stably transfected cell lines and provide evidence for agonist-dependent differential stimulation of second messenger responses.

Sequence variation in the thermostable direct hemolysin-related hemolysin (trh) gene of Vibrio parahaemolyticus

Our previous molecular epidemiologic study with gene probes (H. Shirai, H. Ito, T. Hirayama, Y. Nakamoto, N. Nakabayashi, K. Kumagai, Y. Takeda, and M. Nishibuchi, Infect. Immun. 58:3568-3573, 1990) demonstrated that the gene (trh) encoding a thermostable direct hemolysin-related hemolysin was strongly associated with clinical strains of Vibrio parahaemolyticus. Strain-to-strain variation in the intensities of the hybridization signals observed in the above study also suggested that the trh genes in different strains may have significantly divergent nucleotide sequences. To assess the public health significance of the rare environmental strains which exhibited very weak hybridization signals with the trh gene-specific DNA probe, the trh-like sequence was cloned from one of the environmental strains and the nucleotide sequence was determined in this study. A hemolysin gene (trh2) which was 84% homologous to the trh gene (newly named trh1) and 54.8 to 68.8% homologous to the genes (tdh) encoding thermostable direct hemolysins was detected in the cloned sequence. The trh2 gene product showed a profile of hemolytic activities against various animal erythrocytes different from that of the trh1 gene product. The trh2 gene product was antigenically related (partially identical) to the trh1 and tdh gene products. DNA colony blot and Southern blot hybridization analyses with trh1- and trh2-specific DNA probes showed that the trh1 probe-positive strains exhibiting hybridization signals with varying intensities could be clustered into trh1 and trh2 subgroups. In addition, hybridization analysis with oligonucleotide probes demonstrated significant strain-to-strain variation in the trh1 and trh2 gene sequences.(ABSTRACT TRUNCATED AT 250 WORDS)

Structural Elucidation of Dendranthemosides A and B: Two New beta-Ionone Glucosides from Dendranthema shiwogiku

From the N-BuOH soluble fraction of an MeOH extract of DENDRANTHEMA SHIWOGIKU, two new beta-ionone glucosides and roseoside were isolated, the structures of the new compounds elucidated were 2 and 3, respectively, on the basis of spectroscopic data and the results of an enzymic hydrolysis of 2.

Indonesian medicinal plants. I. Chemical structures of calotroposides A and B, two new oxypregnane-oligoglycosides from the root of Calotropis gigantea (Asclepiadaceae)

Two new oxypregnane-oligoglycosides named calotroposides A (1) and B (2) have been isolated from the root of Calotropis gigantea (Asclepiadaceae), an Indonesian medicinal plant, and their chemical structures have been elucidated by chemical and spectroscopic methods as 12-O-benzoyllineolon 3-O-beta-D-cymaropyranosyl(1----4)-beta-D-oleandropyranosyl( 1----4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)-beta-D- cymaropyranoside and 12-O-benzoyldeacetylmetaplexigenin 3-O-beta-D-cymaropyranosyl(1---4)-beta-D-oleandropyranosyl(- ---4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)- beta-D-cymaropyranoside, respectively.

Reassessment of the prevalence of heat-stable enterotoxin (NAG-ST) among environmental Vibrio cholerae non-O1 strains isolated from Calcutta, India, by using a NAG-ST DNA probe

A collection of 521 environmental isolates of Vibrio cholerae which were previously examined by the suckling mouse assay and found to be negative for the heat-stable enterotoxin NAG-ST were reassessed by a recently developed DNA probe for NAG-ST. A total of 12 (2.3%) of the isolates hybridized with the NAG-ST probe. By using a cholera toxin (CT) DNA probe, the CT gene was detected in six of the strains in the collection, although none of the isolates of V. cholerae non-O1 hybridized with both of the toxin probes. All of the NAG-ST and CT probe-positive strains were hemolysin positive. Thirty-fold-concentrated supernatants of the three representative NAG-ST DNA probe-positive V. cholerae non-O1 strains gave positive fluid accumulation ratios in the suckling mouse assay even after heating (100 degrees C for 5 min) and also inhibited the binding of a NAG-ST monoclonal antibody to the bound NAG-ST in a competitive enzyme-linked immunosorbent assay (ELISA). Likewise, all six CT probe-positive V. cholerae non-O1 strains produced in vitro CT when examined by the CT bead ELISA. HindIII digest patterns of chromosomal DNA from the representative NAG-ST gene-positive strains were visually indistinguishable. Between the groups of NAG-ST probe-positive strains examined, there was a variation in the hybridizable fragments, with one group of strains exhibiting a hybridizable fragment similar to that of the NRT 36 reference strain; a smaller HindIII fragment hybridized with the NAG-ST probe in the other group of strains.(ABSTRACT TRUNCATED AT 250 WORDS)

The enantioselective metabolism of p-cymene in rabbits

p-Cymene (1) was metabolized in rabbits and the following four optically active metabolites, 2-(p-tolyl)-1-propanol (3': R/S = 65:35), 2-(p-tolyl)propanoic acid (5': R/S = 0:100), p-(2-hydroxy-1-methylethyl)benzoic acid (6': R/S = 91:9) and p-(1-carboxyethyl)benzoic acid (8': R/S = 30:70), were isolated in addition to three optically inactive metabolites, 2-(p-tolyl)-2-propanol (2), p-isopropylbenzoic acid (4'), and p-(1-hydroxy-1-methylethyl)benzoic acid (7'). The presumed metabolic pathways of p-cymene in rabbits were confirmed by the administration of the intermediate metabolites (2, 3', 4', and 5'). The enantiomeric ratios of the metabolites, 3' and 6', suggested that omega-hydroxylations of the isopropyl group in 1 and 4' occurred preferentially at the pro-S methyl group. In the metabolism of 1, the S-isomers are predominant in the propanoic acid derivatives, but the R-isomers are rich in the propanol derivatives. It is of interest that the metabolism of 4', however, produced predominantly the corresponding propanol derivative (6'; R/S = 91:9) and propanoic acid derivative (8'; R/S = 80:20) possessing the same R-configuration. Some optically active p-cymene derivatives were also synthesized as standard compounds.

Evaluation of the bead enzyme-linked immunosorbent assay for detection of cholera toxin directly from stool specimens

A highly sensitive bead enzyme-linked immunosorbent assay (bead ELISA) for detection of cholera toxin (CT) was evaluated for direct detection of CT from stool specimens of patients with acute secretory diarrhea. Of the 75 stool samples examined, 59 yielded biochemically, and serologically confirmed strains of Vibrio cholerae O1. The bead ELISA was positive for CT in stool supernatants in 50 (84.7%) of the 59 samples from which V. cholerae O1 was isolated. In addition, the bead ELISA was positive for three stool specimens which were negative by culture. The free CT present in 48 of the 50 stool samples positive by culture for V. cholerae O1 and for CT by bead ELISA was completely absorbed by anti-CT immunoglobulin G. All of the 59 strains of V. cholerae O1 biotype eltor isolated in this study produced in vitro CT. The concentration of CT present in the bead ELISA-positive stool samples ranged between 26 pg/ml and greater than 100 ng/ml. This evaluation study demonstrates that the bead ELISA is a sensitive and simple method for direct detection of CT in nonsterile stool samples, and we recommend routine use of this assay for detection of CT in stool samples and culture supernatants in clinical and reference laboratories.

Alteration of type II regulatory subunit of cAMP-dependent protein kinase in human cisplatin-resistant cells as a basis of collateral sensitivity to 8-chloro-cAMP

A cyclic adenosine 3',5'-monophosphate (cAMP) analogue, 8-chloro-cAMP (8-Cl-cAMP), had a collateral growth-inhibitory effect on a cis-diamminedichloroplatinum(II) (CDDP)-resistant human cancer cell lines (PC-14/CDDP). The non-selective analogues dibutyryl-cAMP, 8-bromo-cAMP and forskolin, which are cAMP agonists, showed far less cytotoxicity than 8-Cl-cAMP in both cell lines. There was no significant difference in cAMP content between PC-14 and PC-14/CDDP. Because 8-Cl-cAMP has been shown to bind selectively to the site I receptor of the type II regulatory subunit (RII) of cAMP-dependent protein kinase, we determined the level of expression of regulatory subunits in PC-14 and PC-14/CDDP cells by photoaffinity labeling. PC-14/CDDP cells had a higher RII level, low site I receptor of type I regulatory subunit (RI) level, and a lower RI/RII ratio than the parental PC-14 cells. Exposure to 8-Cl-cAMP increased the RI and RII level in PC-14/CDDP cells in dose- and time-dependent manners. On the other hand, in parental PC-14 cells, RII was not detected and the levels of RI and RII were not increased by exposure to 8-Cl-cAMP. These results suggested that the change in RI and/or RII levels caused by 8-Cl-cAMP was correlated with 8-Cl-cAMP-induced growth inhibition and that the collateral sensitivity to 8-Cl-cAMP in CDDP-resistant cells was due to the increased RII level. Our results suggest that 8-Cl-cAMP can be used in combination with CDDP and that measurement of RI and RII levels and/or the RI/RII ratio is a useful tool to predict CDDP sensitivity.

Malignant myoepithelioma of minor salivary gland origin

Myoepithelial cells are a significant component of most types of salivary gland tumors. A small but increasing number of case reports have also shown that true myoepithelioma (ME) forms a distinct clinicopathologic entity of salivary gland tumors with unique histologic features, however, the malignant type of ME is exceedingly rare. The present paper reports a case of malignant ME originating from the palatal minor salivary gland. The patient was a 70-year-old Japanese male with recurrent tumor of the palatal region. Pathologically, the tumor consisted of proliferating polygonal-shaped cells and plump spindle cells with cellular atypia and frequent mitoses, forming lumen-less lobuli or strands. Clear tumor cells were also found in part. The stroma was poorly developed without any myxoid or chondroid features. Immunohistochemical study showed positive stainings for S-100 protein, actin and vimentin in the tumor cells. Ultrastructurally, tumor cells had features of myoepithelial cells.

[Isolation of vero-cytotoxin-producing Escherichia coli from cattle and serotyping and toxin-typing of the isolated strains]

Two hundred and sixty-six piglets with diarrhea (from 4 farms), 73 healthy pregnant pig (from 2 farms), 27 calves with diarrhea (from 9 farms) and 47 healthy milk cows (from 1 farm) were examined for Vero-cytotoxin-producing Escherichia coli (VTEC), and 52, 11, 15 and 67 strains of VTEC were isolated from 17 piglets, 11 pregnant pigs, 6 calves and 23 milk cows, respectively. All VTEC strains from the piglets produced only VT2vp, while the strains from the healthy pigs did not produce VT2vp, but did VT1 and/or VT2. Most VTEC strains from calves and cows produced VT2vhb and some produced VT2 and VT1. Serotyping of the isolated strains showed that many strains from the piglets belonged either O139:H1, O141:H4 or O141:HUT, but the strains from the pigs were either R-form or O-untypable. Many strains from the calves and cows were serotyped into O116 or O113, but there were several R-form and O-untypable. From these results, it is suggested that VTEC strains, especially from the pregnant pigs, calves with diarrhea and healthy milk cows, which produced the same type of Verotoxins to that produced by human isolates, may become sources of human infections.

Feto-maternal interaction of IGF-I and its binding proteins in fetal growth

Elevated levels of maternal IGF-I and IGF-binding proteins IGFBP-1 are regulated by placental hormones rather than pituitary control during pregnancy. Maternal IGF-I promotes fetal growth by stimulating nutrient transfer to fetus through placenta and IGFBP-1 suppresses fetal growth by inhibiting IGF-I binding to receptors in placenta. Since IGF-I and IGFBP-1 are produced in placenta and decidua, respectively, fetal growth is regulated by these substances in the locally formed paracrine system.

GM-CSF and G-CSF stimulate the synthesis of histamine and putrescine in the hematopoietic organs in vivo

Histamine and putrescine (a precursor of polyamines) are formed by histidine decarboxylase (HDC) and ornithine decarboxylase (ODC), respectively. Within a few hours after injection of a lipopolysaccharide (LPS) into mice, HDC is induced in the liver, spleen, lung and bone marrow, and ODC is induced in the liver, spleen and bone marrow. Since LPS is known to stimulate the production of various cytokines, the abilities of various cytokines to induce HDC and ODC in the tissues of mice were examined. IL-2, IL-6, IL-8, IFN gamma and M-CSF were ineffective. IL-1 alpha, IL-1 beta, TNF alpha and TNF beta induced HDC and ODC, as does LPS. On the other hand, GM-CSF and G-CSF induced HDC and ODC only in the spleen and bone marrow within a few hours after their injection. These results suggest that, in addition to their roles in inflammation or immune responses, HDC and ODC are also involved in an early stage of hematopoiesis.