Phototrophic N2 fixation suppressed by activated sulfate reduction in anoxic rice soil slurries

Interactions between sulfate reduction (SR) and phototrophic nitrogenase activities were investigated in rice soil slurries mixed with rice straw. Activation of SR by adding exogenous sulfate suppressed acetylene-reducing activity (ARA) of the slurries, which was associated with phototrophic purple bacteria (PB) enumerated to 108-109 MPN g-1 dry weight (dw) soil. Adding 5 mm sodium molybdate, an inhibitor of SR, markedly increased ARA. However, in the slurries receiving both molybdate and exogenous sulfate, the effects declined simultaneously with partial recovery of SR. These results indicate outcompetition of sulfate-reducing bacteria (SRB) with PB in rice soil, when sulfate concentrations are high enough to support SR. The increasing effects of molybdate on ARA continued during the incubation in the sulfate-depleted condition, probably because of absence of SR and toxicity of molybdate to methanogenesis. Accordingly, stopping activities of the competitive microorganisms may be efficient to increase N2 fixation in rice soil.

Direct inhibitory effect of adrenomedullin, calcitonin gene-related peptide, calcitonin, and amylin on cholecystokinin-induced contraction of guinea-pig isolated caecal circular smooth muscle cells

We recently reported the direct inhibitory effect of adrenomedullin on caecal circular smooth muscle cells via cAMP system. This study was designed to determine whether the structurally related peptides to adrenomedullin (i.e.; calcitonin gene-related peptide (CGRP), calcitonin, and amylin) can inhibit the cholecystokinin octapeptide (CCK-8)-induced contractile response by exerting a direct action on guinea-pig caecal circular smooth muscle cells, and to compare the inhibitory potency of these peptides. In addition, to elucidate each intracellular mechanisms, the effects of an inhibitor of cAMP-dependent protein kinase, inhibitors of particulate or soluble guanylate cyclase on the each peptide-induced relaxation were investigated. Adrenomedullin, CGRP, calcitonin, and amylin inhibited the contractile response produced by CCK-8 in a dose-dependent manner, with IC50 values of 0.14 nM, 0.37 nM, 5.4 nM, and 160 nM, respectively. An inhibitor of cAMP-dependent protein kinase significantly inhibited the relaxation produced by all of these peptides. On the contrary, inhibitors of particulate or soluble guanylate cyclase did not have any significant effect on the relaxation produced by these peptides. In this study, we demonstrated the direct inhibitory effects of the structurally related peptides to adrenomedullin (i.e.; CGRP, calcitonin, and amylin) on the isolated caecal circular smooth muscle cells via cAMP system. The order of potency was as follows; adrenomedullin falling dots CGRP > calcitonin > amylin.

Inhibition of methanogens increases photo-dependent nitrogenase activities in anoxic paddy soil amended with rice straw

The interaction between phototrophic dinitrogen fixers and methanogens was examined in soil slurries amended with rice straw using 2-bromoethanesulfonic acid (BES), a specific methanogenic inhibitor. Slurries incubated in light increased phototrophic nitrogenase activity (acetylene reducing activity), and showed growth of phototrophic purple bacteria and reduction of CH(4) emission, indicating outcompetition of purple bacteria with methanogens in photic zones. Adding BES effectively inhibited methane production and markedly increased phototrophic acetylene reducing activity accompanied with acetate accumulation, but did not affect populations of purple bacteria in the slurries. More acetate accumulated in the inhibited slurries incubated in dark. We suggest that increased availability of organic substrates for purple bacteria after stopping methanogenic consumption by BES caused the increased phototrophic acetylene reducing activity. These results indicate that, after purple bacteria grow enough, performance of their N(2) fixation may be limited by substrate availability, which methanogenesis may profoundly influence.

Expression and cellular localization of estrogen receptors alpha and beta in the human fetus

Estrogens exert various biological effects by acting through their native receptors, two of which have been identified to date: estrogen receptors alpha (ERalpha) and beta (ERbeta). In this study we examined the expression and cellular localization of ERalpha and ERbeta in various human fetal tissues by semiquantitative RT-PCR (13 and 20 gestational weeks) and immunohistochemistry (13, 20, and 38 gestational weeks), respectively, to study the possible effects of estrogens on human fetal tissues during development. Relatively high levels of ERbeta expression were detected in various human fetal tissues, whereas those tissues expressing ERbeta had markedly lower levels of ERalpha expression. ERbeta messenger ribonucleic acid expression was especially high in the adrenal gland. ERbeta-immunoreactive protein was localized to the definitive zone, but not in the fetal zone, of the adrenal cortex. Although low levels of ERbeta messenger ribonucleic acid were present in the brain, heart, lung, and kidney, ERbeta immunoreactivity was not detected in these tissues. These results suggest that the effects of estrogens in these tissues are predominantly mediated through ERbeta. ERbeta immunoreactivity was detected in Sertoli cells and spermatogonia in the male reproductive tract and in germ cells in the fetal testis and epididymis. In the female reproductive tract, both ERalpha and ERbeta were immunopositive in epithelium of the oviduct. The results of the present study have demonstrated the possible sites for estrogenic action in the human fetus and suggest that the effects of estrogen via ERbeta may play important roles in human fetal development, especially in the definitive zone of the adrenal cortex, and in the reproductive tissues of the developing fetus.

Intraductal papillary-mucinous tumors of the pancreas: differential diagnosis between benign and malignant tumors by endoscopic ultrasonography

OBJECTIVES

Recently, intraductal papillary-mucinous tumor (IPMT) of the pancreas has increasingly been recognized. However, differential diagnosis between benign and malignant IPMT is often difficult using conventional imaging modalities. The purpose of this study was to retrospectively investigate the value of endoscopic ultrasonography (EUS) for differentiating malignant from benign IPMT.

METHODS

A total of 51 patients with IPMT were preoperatively examined by EUS. The endosonograhic findings were compared with histopathological findings of the resected specimens.

RESULTS

In main duct type IPMT, the diameter of the main pancreatic duct (MPD) was > or =10 mm in seven of the eight malignant tumors, compared with two of the seven benign tumors (p < 0.05). In branch duct type IPMT, three of the four large tumors (>40 mm) with irregular thick septa were malignant lesions. In both main duct type IPMT and branch duct IPMT, eight patients had large mural nodules (>10 mm); seven of the eight tumors were malignant and one of the eight tumors was benign. When the tumor was diagnosed as malignant according to above three findings, EUS was able to differentiate between malignant and benign IPMT with an accuracy of 86%.

CONCLUSIONS

Main duct type tumors with > or =10 mm dilated MPD, branch duct type tumors (>40 mm) with irregular septa, and large mural nodules (>10 mm) strongly suggest malignancy on EUS. EUS would be a useful modality for differentiating between benign and malignant IPMT.

[Accuracy and usefulness of ultraportable hand-carried echocardiography system]

OBJECTIVES

The diagnostic accuracy and usefulness of an ultraportable hand-carried echocardiography system were investigated for assessing ventricular systolic function and severity of mitral valvular regurgitation.

METHODS

The study population consisted of 77 consecutive patients (47 men, 30 women, mean age 63 +/- 15 years). Left ventricular end-diastolic dimension, left ventricular end-systolic dimension and left ventricular ejection fraction were measured using the hand-carried echo system and the data were compared with measurements by the conventional echocardiography system using simple linear regression analysis. Left ventricular wall motion was compared between the systems using a 16-segment model recommended by the American Society of Echocardiography. Severity of mitral regurgitation was assessed by the distance of the regurgitant signal in the left atrium.

RESULTS

Left ventricular end-diastolic dimension, left ventricular end-systolic dimension and left ventricular ejection fraction showed good correlations between hand-carried and conventional echo systems (r = 0.94, 0.91 and 0.81, respectively; each p < 0.0001). The accuracy for assessing left ventricular wall motion was 94% (449 of 480 segments). The echo systems also showed the same degree of diagnostic accuracy for severity of mitral regurgitation.

CONCLUSIONS

The hand-carried echo system provides accurate assessment of left ventricular function and mitral regurgitation simular to conventional echo machines.

Twin pregnancy consisting of 46, XY heterozygous complete mole coexisting with a live fetus

Complete hydatidiform mole and coexistent fetus (CMCF) is a rare occurrence and is associated with an increased risk of persistent gestational trophoblastic diseases. The aim of this study was to reveal a potential risk factor and to determine optimum management of CMCF cases. Molar tissues are cytogenetically divided into two types, homozygous and heterozygous. The molar tissue of our case showed a 46, XY heterozygous complete mole. Genomic DNA was analyzed by the polymerase chain reaction using sets of unlabelled forward and Cy-5-labelled reverse primers for DNA marker loci. The patient developed persistent trophoblastic disease (PTD) with lung metastasis. Since 1980 there have been 13 reports (including our case) that cytogenetically revealed CMCF and clarified the clinical outcome. Nine of the 16 CMCF cases before 21 weeks of gestation and seven of the 12 CMCF cases after 22 weeks of gestation developed PTD. The incidence of PTD from CMCF was not related to the gestational age at termination or delivery. There were 10 case reports that analyzed the zygosity of a mole, heterozygous or homozygous. Two of six homozygous and three of four heterozygous moles in CMCF cases developed PTD. A heterozygous mole is thought to be a high risk factor for the incidence of PTD. Cytogenetic study is clinically useful for the optimum management of CMCF cases.

Immunolocalization of steroidogenic enzymes in the corpus luteum and placenta of the Japanese black bear, Ursus thibetanus japonicus, during pregnancy

The Japanese black bear, Ursus thibetanus japonicus, is a seasonal breeder and shows delayed implantation for several months during pregnancy. The objective of this study was to clarify the steroidogenic capability of the corpus luteum and placenta during pregnancy, including both delayed implantation and fetal development, by immunolocalization of steroidogenic enzymes in these organs of the Japanese black bear. Ovaries and placentae from 15 wild Japanese black bears, which had been killed legally by hunters and were thought to be pregnant, were used in an immunocytochemical study to localize the cholesterol side chain cleavage cytochrome P450 (P450scc), 3beta-hydroxysteroid dehydrogenase (3betaHSD), 17alpha-hydroxylase cytochrome P450 (P450c17) and aromatase cytochrome P450 (P450arom) by the avidin-biotin-peroxidase complex method using polyclonal antisera raised in mammals against P450scc, 3betaHSD, P450c17 and P450arom. P450scc and 3betaHSD were localized in all luteal cells throughout pregnancy. P450c17 was present in a few luteal cells, especially in the outer area of the corpus luteum throughout pregnancy, but the number of positively immunostained cells decreased during the post-implantation period. Cells positively immunostained for P450c17 were significantly smaller than negatively immunostained cells (P < 0.01). P450arom was present sporadically in a few luteal cells throughout pregnancy, but the number of positively immunostained cells decreased during the post-implantation period. The size of cells positively immunostained for P450arom was not significantly different from that of negatively immunostained cells. The whole placenta was negatively immunostained for P450scc, 3betaHSD and P450c17, but P450arom was present in the syncytiotrophoblasts and endothelial cells of maternal blood vessels. These results indicate that, in the Japanese black bear, corpora lutea are a source of progesterone which may play an important role in the maintenance of delayed implantation and fetal development during pregnancy. Corpora lutea have a minimum capability to synthesize androgen in small luteal cells and oestrogen in normal-sized luteal cells during pregnancy, and placentae have the ability to synthesize oestrogen during late pregnancy.

A new diquat derivative appropriate for colourimetric measurements of biological materials in the presence of paraquat

A new colourimetric method is described for the quantification of diquat using a yellow-coloured derivative produced by heating diquat in alkaline solution at 80 degrees C. The absorption maximum of the yellow derivative is 420 nm and the molar absorption coefficient is 2.76 x 10(4) (0.15 in 1 microgram diquat/ml with 1 cm light path). The absorption at 420 nm shows a linear concentration dependence in the range 0.1-10 micrograms/ml and fading of the colour is about 5% after 1 h. Under the same conditions, paraquat does not produce any coloured products. The concentration of diquat in the solution containing both diquat and paraquat can be determined by the absorption of diquat derivative at 420 nm without interference from paraquat. By adding sodium dithionite to the solution the concentration of paraquat can be determined by the absorption of paraquat radicals at 600 nm without interference from diquat, because the yellow derivative does not react with dithionite. This yellow diquat derivative can be extracted completely with cyclohexanol by saturating the solution with Na2SO4. The absorption maximum in cyclohexanol shifts to 440 nm with the same molar absorbance and the same half-band width as in water. Fading of the colour is less than 5% after 24 h in cyclohexanol. Perchloric acid (3%) and trichloroacetic acid (4.5%) which are often used for deproteinization of tissue homogenates, do not inhibit production of the coloured derivative at pH 13.5 or extraction of the derivative with cyclohexanol. This method is suitable for a quick determination of small amounts of diquat in tissues, since the extraction with cyclohexanol not only concentrates the derivative rapidly but also quite efficiently eliminates the coloured substances in tissue homogenates. The detection limit of diquat is 0.02 microgram/ml for blood and 0.05 microgram/g for liver when 1 ml or 1 g is used for analysis. In three human cases of fatal intoxication, both paraquat and diquat were quantified using 50 microliters of serum. In non-toxic dosing of diquat to rats for 14 days, the diquat level was highest in the spleen followed by the kidneys.

Isochromosome consisting of terminal short arm and proximal long arm X in a girl with short stature

A 16-year-old girl with short stature, short neck, shield chest, and cubitus valgus was studied. FISH analyses of her structurally altered X chromosome showed a der(X)- (wcpX+,TelXp/Yp++,SHOX++,STS++,KAL-, 37A12-,DXZ1+,XIST++,97L7++,300O13-,404F- 18-,417G15-,404F18-,140A-,TelXq/Yq-). These results, together with the high-resolution banding analysis, indicated her karyotype to be 46,X,der(X)(Xpter-->Xp22.3::Xq22.3--> cen-->Xq22.3::Xp22.3-->Xpter). The der(X) was an isochromosome, consisting of duplicated terminal short arms and duplicated proximal long arms. This in turn suggested that the chromosome was formed through pericentric inversion of an X chromosome, followed by isochromosome formation through sister chromatid exchange at Xp, close to the centromere. Replication R-banding analysis showed that the abnormal X chromosome was late replicating. Analysis of digestion patterns with a methylation-sensitive restriction endonuclease of the phosphoglycerate kinase 1 gene, located in Xq13.3, indicated that its inactivation patterns were completely skewed.

Identification of proacrosin binding protein sp32 precursor as a human cancer/testis antigen

Serological expression cloning of antigens eliciting a humoral immune response to a syngeneic mouse sarcoma identified pem (mouse placenta and embryonic expression gene) as a new member of the cancer/testis family. To identify the human homologue of pem, mouse pem sequences and pem-related expressed sequence tags from human testis were used as PCR primers for amplification using human testis cDNA. However, rather than pem, another gene, designated OY-TES-1, was isolated and found to be the human homologue of proacrosin binding protein sp32 precursor originally identified in mouse, guinea pig, and pig. OY-TES-1 maps to chromosome 12p12-p13 and contains 10 exons. Southern blot analysis suggests the presence of two OY-TES-1-related genes in the human genome. In normal tissues, OY-TES-1 mRNA was expressed only in testis, whereas in malignant tissues, a variable proportion of a wide array of cancers, including bladder, breast, lung, liver, and colon cancers, expressed OY-TES-1. Serological survey of 362 cancer patients with a range of different cancers showed antibody to OY-TES-1 in 25 patients. No OY-TES-1 sera reactivity was found in 20 normal individuals. These findings indicate that OY-TES-1 is an additional member of the cancer/testis family of antigens and that OY-TES-1 is immunogenic in humans.

Preoperative evaluation of submucosal invasive colorectal cancer using a 15-MHz ultrasound miniprobe

BACKGROUND AND STUDY AIMS

Recently, it was reported that focal submucosal invasive colorectal cancer could be treated by polypectomy or endoscopic mucosal resection (EMR) because of the rarity of lymph-node metastasis. Our objective was to examine the accuracy and efficacy of a 15-MHz ultrasound miniprobe in the preoperative evaluation of the degree of submucosal invasion in colorectal cancer.

PATIENTS AND METHODS

A total of 35 patients with submucosal invasive colorectal cancer who underwent ultrasonography with a miniprobe were studied prospectively. The results of this imaging were compared with the histologic findings in resected specimens.

RESULTS

Although the accuracy of the miniprobe in categorizing submucosal invasion into three subclasses (SM1, invasion limited to the upper third; SM2, limited to the middle third; SM3, limited to the lower third) was low (37.1%; 13/35), the accuracy in differentiation between < or = SMI (M and SMI) and > or = SM2 (SM2, SM3, MP, and S) was 85.7 % (30/35).

CONCLUSIONS

The miniprobe can be useful for therapeutic decision-making in submucosal invasive colorectal cancer.

The interval between flexible sigmoidoscopy screening examinations can be expanded beyond five years

BACKGROUND/AIMS

As one of the methods for colorectal cancer screening, asymptomatic average-risk persons aged > or = 50 years are recommended to undergo flexible sigmoidoscopy screening every 5 years. We evaluate whether the interval between examinations can be extended beyond 5 years.

METHODOLOGY

A total of 192 asymptomatic average-risk subjects were studied, all of whom had undergone a initial negative examination on a flexible sigmoidoscopy screening at age > or = 50 years and a second examination at least 3 years later. The study population was divided into three groups according to the interval between examinations, which was 3-5 years in Group A, 5-6 years in Group B, and 6-8 years in Group C.

RESULTS

The incidence of neoplasms was compared among the three subjects groups, and it was found to be similar: 11/96 (11.5%) in group A, 4/55 (7.3%) in group B, and 5/41 (12.2%) in group C. All detected adenomas were less than 10 mm in diameter, and none contained a villous component or high-grade dysplasia. No cancers were found in the study.

CONCLUSIONS

The results suggest that the interval for screening sigmoidoscopy may be extended beyond 5 years in persons showing negative results on an initial examination.

Development of novel telomerase inhibitors based on a bisindole unit

Telomerase is the enzyme that elongates telomere repeat at the ends of a chromosome. As high telomerase activity is observed in most cancer cells, inhibitors of human telomerase have been expected as new chemotherapeutic agents for cancer. We describe here the discovery of novel inhibitors with IC50 values in the submicromolar range. The structure of the novel inhibitors will be useful as a scaffold for construction of the library in the search for telomerase inhibitors.

Introduction of antisense CD44S CDNA down-regulates expression of overall CD44 isoforms and inhibits tumor growth and metastasis in highly metastatic colon carcinoma cells

We created antisense CD44 transfectants using LS174T, a colon adenocarcinoma cell line and assessed the effects of overall CD44 down-regulation on colorectal tumor growth and metastasis. The expression of antisense CD44s (the standard form of CD44) cDNA markedly inhibited the overall expression of CD44 variants. In vitro studies showed a significantly reduced ability of the stable antisense transfectants (LS174TAS1 and LS174TAS2) to bind hyaluronate and osteopontin, ligands for CD44. These cells developed tumors more slowly than controls (parental LS174T and mock transfectants) when the cells were subcutaneously injected into SCID mice. However, in vitro proliferation assays demonstrated no significant difference between the antisense transfectants and the controls on a hyaluronate-coated surface, suggesting the participation of ligands other than hyaluronate in tumor growth in vivo. Intrasplenic injection of parental LS174T cells produced colonies in the liver in 10 of 11 mice, whereas mice injected with the antisense transfectants were completely free of metastasis. In peritoneal dissemination, the weight of nodules and amount of ascites were significantly reduced in LS174TAS1 and AS2 compared with the controls. In vitro adhesion assays between the transfectants or controls and human peritoneal mesothelial cells revealed that the binding of LS174T cells to mesothelial cells was partly mediated by CD44-hyaluronate interaction. These data suggest that CD44-hyaluronate interaction plays a crucial role in peritoneal dissemination in colorectal carcinoma. The results of our study demonstrate the possible application of antisense CD44s to the treatment of colorectal carcinoma.

Introduction of antisense CD44S CDNA down-regulates expression of overall CD44 isoforms and inhibits tumor growth and metastasis in highly metastatic colon carcinoma cells

We created antisense CD44 transfectants using LS174T, a colon adenocarcinoma cell line and assessed the effects of overall CD44 down-regulation on colorectal tumor growth and metastasis. The expression of antisense CD44s (the standard form of CD44) cDNA markedly inhibited the overall expression of CD44 variants. In vitro studies showed a significantly reduced ability of the stable antisense transfectants (LS174TAS1 and LS174TAS2) to bind hyaluronate and osteopontin, ligands for CD44. These cells developed tumors more slowly than controls (parental LS174T and mock transfectants) when the cells were subcutaneously injected into SCID mice. However, in vitro proliferation assays demonstrated no significant difference between the antisense transfectants and the controls on a hyaluronate-coated surface, suggesting the participation of ligands other than hyaluronate in tumor growth in vivo. Intrasplenic injection of parental LS174T cells produced colonies in the liver in 10 of 11 mice, whereas mice injected with the antisense transfectants were completely free of metastasis. In peritoneal dissemination, the weight of nodules and amount of ascites were significantly reduced in LS174TAS1 and AS2 compared with the controls. In vitro adhesion assays between the transfectants or controls and human peritoneal mesothelial cells revealed that the binding of LS174T cells to mesothelial cells was partly mediated by CD44-hyaluronate interaction. These data suggest that CD44-hyaluronate interaction plays a crucial role in peritoneal dissemination in colorectal carcinoma. The results of our study demonstrate the possible application of antisense CD44s to the treatment of colorectal carcinoma.

Two cases of colonic adenomatous polyps accompanied by a migrated surgical suture

A 56-year-old man and a 70-year-old woman, with histories of left colectomy and appendectomy respectively, were admitted to our hospital. In both cases, colonoscopy showed a pedunculated colonic polyp in the ascending colon, and a silk suture became visible in the stalk during polypectomy. The histological diagnosis was adenoma. These two cases constitute the first report of colonic adenomatous polyps accompanied by suture migration.

Neurosarcoidosis without systemic sarcoidosis--case report

A 20-year-old male presented with symptoms of isolated neurosarcoidosis including epilepsy. Magnetic resonance imaging disclosed multiple enhanced right temporal and frontal lesions. Cerebrospinal fluid examination identified mild lymphocytic pleocytosis, and histological examination of a stereotactic brain biopsy specimen demonstrated noncaseating granulomas, so fungal or other inflammatory or granulomatous diseases were excluded. The diagnosis was cerebral sarcoidosis, despite the absence of systemic manifestations. Corticosteroid therapy improved his neurological state and radiological findings. Neurosarcoidosis is a well-recognized occurrence in systemic sarcoidosis, but diagnosis may be difficult in the absence of extracerebral manifestations.

Rate and equilibrium constants for the epimerization of the endothelin receptor antagonist J-104,132 in aqueous solution

The degradation of [5S-[5alpha,6beta,7alpha(R*)]]-2-butyl-5-(1,3-benzodioxol-5-yl)-7-[(2-carboxypropyl)-4-methoxyphenyl]-6-dihydro-5H-cyclopenta[b]pyridine-6-carboxylic acid (J-104,132) was studied in aqueous solution as a function of temperature and pH. The degradation reaction does not proceed to completion; rather, a stable equilibrium is attained in which approximately 2% of the degradate is produced. Kinetic data for the formation of the degradate are analyzed using an integrated form of the rate law for a reversible first-order reaction, and the forward and reverse rate constants and overall equilibrium constants are presented. Isolation and spectroscopic structural determination indicate that the degradate is the C7 beta-epimer of the drug. A mechanism for the epimerization reaction involving a novel enamine-like intermediate is proposed and shown to be consistent with the kinetic data. The rate and equilibrium constants are used to predict the room temperature stability of an injectable formulation of J-104,132, and these predictions are compared to actual data from long-term stability studies. It is concluded that the preformulation kinetic studies provide essential data needed for optimum drug product development.

Introduction of antisense CD44S CDNA down-regulates expression of overall CD44 isoforms and inhibits tumor growth and metastasis in highly metastatic colon carcinoma cells

We created antisense CD44 transfectants using LS174T, a colon adenocarcinoma cell line and assessed the effects of overall CD44 down-regulation on colorectal tumor growth and metastasis. The expression of antisense CD44s (the standard form of CD44) cDNA markedly inhibited the overall expression of CD44 variants. In vitro studies showed a significantly reduced ability of the stable antisense transfectants (LS174TAS1 and LS174TAS2) to bind hyaluronate and osteopontin, ligands for CD44. These cells developed tumors more slowly than controls (parental LS174T and mock transfectants) when the cells were subcutaneously injected into SCID mice. However, in vitro proliferation assays demonstrated no significant difference between the antisense transfectants and the controls on a hyaluronate-coated surface, suggesting the participation of ligands other than hyaluronate in tumor growth in vivo. Intrasplenic injection of parental LS174T cells produced colonies in the liver in 10 of 11 mice, whereas mice injected with the antisense transfectants were completely free of metastasis. In peritoneal dissemination, the weight of nodules and amount of ascites were significantly reduced in LS174TAS1 and AS2 compared with the controls. In vitro adhesion assays between the transfectants or controls and human peritoneal mesothelial cells revealed that the binding of LS174T cells to mesothelial cells was partly mediated by CD44-hyaluronate interaction. These data suggest that CD44-hyaluronate interaction plays a crucial role in peritoneal dissemination in colorectal carcinoma. The results of our study demonstrate the possible application of antisense CD44s to the treatment of colorectal carcinoma.

Strain differences in SA gene expression in brain and kidney of normotensive and hypertensive rats

1. In situ hybridization done using a 35S-cRNA probe was carried out to obtain information on the expressions of the SA gene in brains and kidneys of the spontaneously hypertensive rat (SHR) strain obtained from the Izumo colony (/Izm) and from Charles River Laboratories (/Crj). 2. In the brain, SA mRNA expression was most abundantly observed in epithelial cells of the choroid plexus. High to moderate levels was present on neurons of the CA1-CA4 pyramidal cell layer and the dentate gyrus of the hippocampus and the cerebellar Purkinje cell layer. The solitary tract nucleus and the dorsal motor nucleus of the vagus expressed the SA gene at very low levels. An increase in the expression was noted in the choroid plexus of WKY/Crj; there was no difference, however, in expression levels of other brain areas between WKY/Izm, SHR/Izm, and SHRSP/Izm, and between WKY/Crj and SHR/Crj. 3. In the kidney, expression signals of SA mRNA were observed in renal medullary rays and focal cortex of WKY/Izm, SHR/Izm, SHRSP/Izm, and SHR/Crj, whereas mRNA expression in the WKY/Crj kidney was observed in medullary rays and outer strips of the outer medulla. Microscopically, hybridization signals were predominant in the proximal tubules. 4. Expression densities decreased only in the kidney of WKY/Crj in 4-and 8-week-old rats, but not in the WKY/Izm kidney, compared with findings in SHR and SHRSP kidneys. These observations are in good agreement with data from Northern blot analysis. 5. The SA gene expressions in the brain and the kidney seem not to relate to states of elevated blood pressure, but rather to strain differences. Abundant expressions in the brain and the kidney may mean that the SA gene plays a role in the water-electrolyte transport system. It is noteworthy that there are neuronal expressions of the SA gene in hippocampal pyramidal cells and cerebellar Purkinje cells.

Estrogen secreting adrenal adenocarcinoma in an 18-month-old boy: aromatase activity, protein expression, mRNA and utilization of gonadal type promoter

We examined clinical, endocrinological and molecular biological aspects of an estrogen-secreting adrenal carcinoma in an 18-month-old male to clarify the pathogenesis of this condition. An 18-month-old boy was referred for evaluation of progressive bilateral gynecomastia and appearance of pubic hair. The patient had elevated plasma estradiol (349 pg/ml) and testosterone (260 ng/dl) levels that completely suppressed FSH and LH levels, and was subsequently diagnosed with an adrenal tumor on the right side. After removal of a 300-g adenocarcinoma, gynecomastia regressed and essentially normal hormone levels were restored. Aromatase activity in the tumor tissue determined by the 3H-water method was 71.0-104.4 pmol/min/mg protein. High levels of aromatase protein and mRNA in the tumor tissue were also demonstrated, while neither aromatase activity nor protein was detected in normal adrenal glands. To investigate the regulation of aromatase expression in the adrenal carcinoma, we examined the usage of alternate promoters responsible for aromatase gene transcription. In the present case, the amounts of aromatase mRNA utilizing gonadal types of exon 1c (1.3) and 1d (II) were significantly higher than those that using other exon 1s. This result suggested that the utilization of a gonadal-type exon 1 might be involved in the over-production of aromatase in estrogen-secreting adrenal carcinoma.

Chiral overcrowded alkenes; asymmetric synthesis of (3S,3'S)-(M, M)-(E)-(+)-1,1',2,2',3,3',4,4'-octahydro-3,3',7,7'-tetramethyl-4, 4'-biphenanthrylidenes

An asymmetric synthesis route towards (3S,3'S)-(M,M)-(E)-(+)-1,1',2, 2',3,3',4,4'-octahydro-3,3',7,7'-tetramethyl-4,4'-biphenanthrylidene was developed using the Evans procedure as a key step. The absolute configurations of the title compound and of its parent ketone were determined by CD spectroscopy and could be correlated with the stereochemical results of the asymmetric alkylation. Furthermore, a comparison was made with the known (3R,3'R)-(P,P)-(E)-(-)-1,1',2,2', 3,3',4,4'-octahydro-3,3',7,7'-dimethyl-4,4'-biphenanthrylidene. Finally, the X-ray crystallographic analysis of (3S,3'S)-(M, M)-(E)-(+)-1,1',2,2',3,3',4,4'-octahydro-3,3',7,7'-tetramethyl-4, 4'-biphenanthrylidene is presented.

Development and evaluation of muscarinic cholinergic receptor ligands N-[11C]ethyl-4-piperidyl benzilate and N-[11C]propyl-4-piperidyl benzilate: a PET study in comparison with N-[11C]methyl-4-piperidyl benzilate in the conscious monkey brain

The muscarinic cholinergic receptor ligands N-[(11)C]ethyl-4-piperidyl benzilate (4-EPB) and N-[(11)C]propyl-4-piperidyl benzilate (4-PPB) were developed and evaluated in comparison with N-[(11)C]methyl-4-piperidyl benzilate (4-MPB) in the conscious monkey brain using positron emission tomography (PET). Time-activity curves of [(11)C]4-EPB, unlike [(11)C]4-MPB, showed peaks within 91 min in regions rich in muscarinic receptors. [(11)C]4-PPB showed no specific binding even in the regions rich in these receptors. These observation demonstrated that increases in [(11)C]alkyl chain length could alter the kinetic properties of receptor ligands for PET.

The invasion of Mycobacterium tuberculosis into non-phagocytic cells

To explore the ability of tubercle bacilli to invade and survive within non-phagocytic cells, we used in this study a human fibroblast cell line, WI-38, derived from normal embryonic lung and a human epithelial cell line, SQ-5, derived from lung squamous cell carcinoma. Live M. tuberculosis Erdman and M. tuberculosis H37Rv invaded WI-38 cells more efficiently than live M. tuberculosis H37Ra, M. bovis Ravenel, M. bovis BCG Tokyo and M. bovis BCG Pasteur. The capability of tubercle bacilli to invade WI-38 cells was Erdman > or = H37Rv > BCG Pasteur [symbol: see text] M. bovis Ravenel [symbol: see text] BCG Tokyo > H37Ra. A similar invasive ability was observed using SQ-5 cells. In contrast with live bacilli, heat-killed bacilli failed to invade WI-38 cells, whereas they were detected within SQ-5 cells. These results and incorporation of latex beads suggest that SQ-5 cells, but not WI-38 cells, possess phagocytic activity. H37Rv multiplied most actively within WI-38 cells when compared to H37Ra and BCG Tokyo, suggesting that the ability to invade and survive within non-phagocytic cells reflects the more active invasion of virulent M. tuberculosis than avirulent M. tuberculosis. The assay system used in this study may help us to clarify the virulence of tubercle bacilli in vitro.

Analysis of estrogen receptor alpha and beta in endometrial carcinomas: correlation with ER beta and clinicopathologic findings in 45 cases

Estrogens play important roles in the pathogenesis of the great majority of endometrial endometrioid adenocarcinoma. Recently, a novel estrogen receptor (ER), ER beta, has been characterized, but little is known about the status of ER beta in endometrial carcinoma. We therefore examined expression of both ER alpha and ER beta in 45 cases of endometrioid endometrial adenocarcinoma using mRNA in situ hybridization, reverse transcription and polymerase chain reaction (RT-PCR), and immunohistochemistry. We also correlated the findings with various clinicopathologic parameters in these cases to examine their possible biologic significance. Accumulation of mRNA hybridization signals for both ER alpha and ER beta was detected predominantly in the cytoplasm of carcinoma cells, and to a lesser extent in some stromal cells. ER beta mRNA was detected in 16/45 cases (35.6%), and ER alpha mRNA hybridization signals were detected in 36/45 cases (80.0%). Among the 16 ER beta positive cases, 15 cases also had ER alpha mRNA hybridization signals. In the cases that expressed both ER alpha and ER beta, ER alpha mRNA hybridization signals were more widely distributed than ER beta mRNA. In 21 cases, carcinoma cells had ER alpha mRNA hybridization signals but not ER beta mRNA. There was a statistically significant positive correlation between the results of mRNA in situ hybridization and semiquantitative RT-PCR or immunohistochemistry for both ER alpha and ER beta. There were no significant correlations between ER beta mRNA expression and PR labeling index, Ki67 LI, age, or histologic grade. The results from our study indicate that ER beta is coexpressed with ER alpha, and that the estrogenic effects occur predominantly through ER alpha in endometrial carcinomas.

Preoperative staging of rectal cancer using a 7.5 MHz front-loading US probe

BACKGROUND

Conventional echoendoscopes have disadvantages when used for staging colorectal cancer including the inability to pass the instrument through tight stenosis and limited maneuverability. This study evaluated the preoperative use of a newly developed 7.5 MHz front-loading ultrasound probe (FLUP) for local staging of rectal cancer.

METHODS

A 7.5 MHz FLUP, diameter 7.3 mm, was used in this study. The mechanical shaft portion of the probe can be passed in retrograde fashion through the accessory channel of a standard colonoscope. Thirty-nine patients with rectal cancer underwent ultrasonography with this probe. The tumors were staged using the TNM system, and the results were compared with the histologic findings of the resected specimens.

RESULTS

The FLUP proved to be satisfactory, with respect to maneuverability, for traversing stenosis and accurate recognition of small tumors under direct endoscopic control. The accuracy of the FLUP for T staging was 82% (32 of 39) for all tumors, 90% in pT1, and 79% in pT2 to pT4 tumors. The accuracy of the FLUP for N staging was 72% (23 of 32) overall. The sensitivity was 83%, the specificity was 65%, the positive predictive value was 59%, and the negative predictive value was 87%.

CONCLUSIONS

The 7.5 MHz FLUP appears to be useful for preoperative local staging of rectal cancer. This system makes it technically easier to image small cancers as well as advanced rectal cancers.

Down-regulation of CD98 in melphalan-resistant myeloma cells with reduced drug uptake

Although melphalan has been used as a therapeutic reagent for multiple myeloma, many patients become refractory. To elucidate the mechanism of resistance to melphalan, we generated a melphalan-resistant myeloma cell line, KHM-11(EMS), by treating a parental line, KHM-11, with a mutagen, ethylmethanesulfonate. KHM-11(EMS) is 55 times more resistant to melphalan. gamma-Glutamylcysteine synthetase, P-glycoprotein, multidrug-resistance-associated protein, lung-resistance-related protein and the Bcl-2 family of proteins were not responsible for the drug resistance in KHM-11(EMS). Intracellular incorporation of melphalan to myeloma cells was determined by using [(14)C]-labeled melphalan. Accumulation of melphalan in KHM-11(EMS) was 43% of KHM-11, while the efflux rates were comparable in both cell lines. The uptake of melphalan was inhibited by the addition of L-phenylalanine, indicating that melphalan is incorporated through the L-phenylalanine transporter as reported previously. Expression of CD98, which was recently cloned as an L-phenylalanine transporter, was 6-fold decreased in KHM-11(EMS), suggesting that CD98 may be correlated with the incorporation of melphalan. CD98 expression and incorporation of melphalan were analyzed in fresh purified myeloma cells from 5 patients. All myeloma cells from 4 cases expressed CD98 at a high level and incorporated melphalan. However, tumor cells from 1 case expressed CD98 at low levels and did not incorporate melphalan. Taken together, reduced melphalan uptake could be responsible for the drug resistance in KHM-11(EMS), and down-regulation of CD98 may be related to this phenomenon. Further investigation of the correlation between impaired drug uptake and down-regulation of CD98 in myeloma cells should be important to understand the mechanism of resistance to melphalan.

Cholinergic neuronal modulation alters dopamine D2 receptor availability in vivo by regulating receptor affinity induced by facilitated synaptic dopamine turnover: positron emission tomography studies with microdialysis in the conscious monkey brain

To evaluate the cholinergic and dopaminergic neuronal interaction in the striatum, the effects of scopolamine, a muscarinic cholinergic antagonist, on the striatal dopaminergic system were evaluated multi-parametrically in the conscious monkey brain using high-resolution positron emission tomography in combination with microdialysis. l-3,4-Dihydroxyphenylalanine (l-[beta-(11)C]DOPA) and 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane ([beta-(11)C]CFT) were used to measure dopamine synthesis rate and dopamine transporter (DAT) availability, respectively. For assessment of dopamine D(2) receptor binding in vivo, [(11)C]raclopride was applied because this labeled compound, which has relatively low affinity to dopamine D(2) receptors, was hypothesized to be sensitive to the striatal synaptic dopamine concentration. Systemic administration of scopolamine at doses of 10 and 100 microg/kg dose-dependently increased both dopamine synthesis and DAT availability as measured by l-[beta-(11)C]DOPA and [beta-(11)C]CFT, respectively. Scopolamine decreased the binding of [(11)C]raclopride in a dose-dependent manner. Scopolamine induced no significant changes in dopamine concentration in the striatal extracellular fluid (ECF) as determined by microdialysis. However, scopolamine dose-dependently facilitated the striatal ECF dopamine induced by the DAT inhibitor GBR12909 at a dose of 0.5 mg/kg. Scatchard plot analysis in vivo of [(11)C]raclopride revealed that scopolamine reduced the apparent affinity of dopamine D(2) receptors. These results suggested that the inhibition of muscarinic cholinergic neuronal activity modulates dopamine turnover in the striatum by simultaneous enhancement of the dynamics of dopamine synthesis and DAT availability, resulting in no significant changes in apparent "static" ECF dopamine level but showing a decrease in [(11)C]raclopride binding in vivo attributable to the reduction of affinity of dopamine D(2) receptors.

Enantiomeric excess of a cruciferous phytoalexin, spirobrassinin, and its enantiomeric enrichment in an achiral HPLC system

Enantiomeric purity of a cruciferous phytoalexin, spirobrassinin (1), was determined by chiral HPLC analysis. The enantiomeric excesses of two natural spirobrassinin fractions separated by nonchiral chromatography were considerably different. A significant enantiomeric enrichment was observed during the nonchiral chromatographic separation of an artificial enantiomeric mixture of 1.

Extracellular adenosine 5'-ATP-induced calcium signaling in isolated vestibular ganglion cells of the guinea pig

Extracellular adenosine 5'-triphosphate (ATP)-induced intracellular calcium concentration ([Ca2+]i) changes in acutely isolated vestibular ganglion cells (VGCs) of the guinea pig were investigated using the Ca2+ -sensitive dye Fura-2. Extracellular ATP induced an increase in [Ca2+]i in VGCs in a dose-dependent manner. ATP induced an increase in [Ca2+]i even in the absence of extracellular Ca2+ (1 mM Ethylene Glycol-bis (beta-aminoethyl Ether) N,N,N',N'-Tetraacetic Acid (EGTA)), thus suggesting that ATP induces Ca2+ release from the intracellular stores. The P2-receptor antagonists suramin and reactive blue 2 inhibited the ATP-induced [Ca2+]i increase in a dose-dependent manner. The P1-receptor agonist adenosine did not induce any changes in [Ca2+]i. These results suggest that VGCs may possess a P2-purinergic receptor but not a P1-purinergic receptor. La3+, a receptor-mediated calcium channel blocker, inhibited the ATP-induced [Ca2+]i increase but, in contrast, nifedipine, a L-type calcium channel blocker, did not. These results suggest that ATP induces both a Ca2+ -release from the intracellular stores and a Ca2+ influx from the extracellular space through La3+ -sensitive and nifedipine-insensitive Ca2+ channels in VGCs. Our results also suggest that extracellular ATP may act as a neurotransmitter or neuromodulator of the vestibular peripheral system in the guinea pig.

Ontogeny of aromatase and tyrosine hydroxylase activity and of aromatase-immunoreactive cells in the preoptic area of male and female Japanese quail

The aromatization of testosterone into oestrogens plays a key role in the control of many behavioural and physiological aspects of reproduction. In the quail preoptic area (POA), aromatase activity and the number of aromatase-immunoreactive (ARO-ir) cells are sexually differentiated (males > females). This sex difference is implicated in the control of the sexually dimorphic behavioural response of quail to testosterone. We analysed the ontogenetic development of this sex difference by measuring aromatase activity and counting ARO-ir cells in the POA of males and females from day 1 post hatch to sexual maturity. We investigated in parallel another enzyme: tyrosine hydroxylase, the rate limiting step in catecholamine synthesis. Between hatching and 4 weeks of age, aromatase activity levels were low and equal in males and females. Aromatase activity then markedly increased in both sexes when subjects initiated their sexual maturation but this increase was more pronounced in males so that a marked difference in aromatase activity was present in 6 and 8 week-old subjects. Tyrosine hydroxylase activity progressively increased with age starting immediately after hatching and there was no abrupt modification in the slope of this increase when birds became sexually mature. No sex difference was detected in the activity of this enzyme. The number of ARO-ir cells in the POA progressively increased with age starting at hatching. No sex difference in ARO-ir cell numbers could be detected before subjects reached full sexual maturity. The analysis of the three-dimensional organization of ARO-ir cells in the POA revealed that, with increasing ages, ARO-ir cells acquire a progressively more lateral position: they are largely periventricular in young birds but they are found at higher density in the lateral part of the medial preoptic nucleus in adults. These data indicate that aromatase activity differentiates sexually when birds reach sexual maturity presumably under the activating effects of the increased testosterone levels in males. The number of ARO-ir cells, however, begins to increase in a non sexually differentiated manner before the rise in plasma testosterone in parallel with the increased tyrosine hydroxylase activity. Whether this temporal coincidence results from a general ontogenetic pattern or from more direct causal links remains to be established.

Adenosine and selective A(2A) receptor agonists reduce ischemia/reperfusion injury of rat liver mainly by inhibiting leukocyte activation

To examine whether adenosine reduces ischemia/reperfusion (I/R)-induced liver injury by inhibiting leukocyte activation via A(2) receptor (A(2)R) stimulation, we investigated the effects of adenosine and selective A(2A) receptor (A(2A)R) agonists (YT-146 and CGS21680C) on I/R-induced liver injury in rats. Adenosine, YT-146, and CGS21680C, in the concentration of 10(-7) to 10(-5) M, significantly inhibited neutrophil elastase release by about 30 to 40% and increased intracellular Ca(2+) concentrations in isolated neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine (fMLP) in vitro. Adenosine, YT-146, and CGS21680C, in the concentration of 10(-7) to 10(-5) M, significantly inhibited tumor necrosis factor (TNF)-alpha production by monocytes stimulated with endotoxin by about 50%. Although ZM241385, a selective A(2A)R antagonist, significantly enhanced the increase in neutrophil elastase release and intracellular Ca(2+) concentrations in neutrophils stimulated with fMLP, this agent did not affect the endotoxin-induced TNF-alpha production by monocytes. Rats were subjected to liver ischemia for 60 min. Serum levels of transaminases increased after hepatic I/R, peaking at 12 h after reperfusion. The i.v. infusion of adenosine (1 and 10 mg/kg/h), YT-146 (0.1 and 1 mg/kg/h), and CGS21680C (0.1 and 1 mg/kg/h) significantly inhibited the I/R-induced increase in serum transaminase levels 12 h after reperfusion. The I/R-induced decrease in hepatic tissue blood flow was significantly prevented by adenosine and YT-146. Hepatic levels of TNF-alpha, cytokine-induced neutrophil chemoattractant (equivalent to human interleukin-8), and myeloperoxidase were significantly increased after I/R. These increases were significantly inhibited by the administration of adenosine, YT-146, and CGS21680C. Although the histological neutrophil accumulation in the liver was significantly increased after I/R as evaluated by the naphthol AS-D chloroacetate technique, the administration of adenosine, YT-146, and CGS21680C significantly inhibited this increase. These findings suggest that adenosine reduces I/R-induced liver injury both by inhibiting the synthesis of inflammatory mediators and by inhibiting neutrophil degranulation directly, probably through A(2A)R stimulation.

Extended radical Whipple resection for cancer of the pancreatic head: operative procedure and results

Pancreatoduodenectomy is now the most fundamental operation for cancer of the pancreatic head. However, with the conventional operative procedure, the resection rate is low and long-term results are extremely poor. We introduced an extended radical Whipple operation in 1978 to improve surgical curability. Systemic dissection of extended lymph nodes and plexuses and en bloc resection of the portal vein was the basic concept. The resection rate for cancer of the pancreatic head has improved from 7-20 to 50%. The curative resection rate has also improved from 10 to 40-50%. The extended procedure did not increase the risk of the Whipple operation. When curative surgery was performed, good long-term survival was expected even in cases of extensive invasion to the portal vein. As a result, 11 patients who underwent curative surgery have survived for a long period of time. At present, however, the majority of patients are in an advanced stage at diagnosis and extended radical operation plays an important role in the curative therapy for this condition.

Establishment and characterization of a CD95 (Fas/Apo-1)-negative myeloma cell line

Although expression of CD95 (Fas/Apo-1) on myeloma cells has been reported, its significance is not clearly understood. We established a myeloma cell line, KHM-11ad (11ad), from a parental cell line, KHM-11, by collecting cells adhered to a plastic dish. KHM-11 cells have been reported to be positive for CD45 and CD95 (Fas/Apo1), and negative for a myelomonocytic antigen, CD13. Interestingly, CD95 was not detected in 11ad. Expression of CD45 was also significantly decreased in 11ad cells while expression of CD13 was detected in these cells. The growth rate of 11ad cells was 1.7 times lower than that of KHM-11 cells. Analysis of adhesion molecules showed that expression of VLA4 and CD44 was significantly suppressed in 11ad. The IC50 of melphalan (L-PAM) for 11ad cells was 50 times higher than that for KHM-11, indicating that 11ad is significantly refractory to L-PAM than KHM-11 cells. Induction of apoptosis by doxorubicin and cycloheximide was suppressed in 11ad cells compared with those in KHM-11 cells. Western blot analysis for Bcl-2 family of proteins showed that Bax was expressed at a 2.2 times lower level in 11ad cells than in KHM-11 cells while there was no difference in expression of Bcl-2, Bcl-Xs nor Bcl-XL. These results suggest that CD95-negative myeloma cells may have characteristics as follows: (1) slow proliferation; (2) low sensitivity to apoptosis; (3) low expression of VLA4, CD44 and Bax. Although these intraclonal variations were based on the findings of cell lines, these may reflect similar variations in vivo. The 11ad line may be a suitable model for analyzing intraclonal variation of myeloma cells.

Localization and controls of aromatase in the quail spinal cord

In adult male and female Japanese quail, aromatase-immunoreactive cells were identified in the spinal dorsal horns from the upper cervical segments to the lower caudal area. These immunoreactive cells are located mostly in laminae I-III, with additional sparse cells being present in the medial part of lamina V and, at the cervical level exclusively, in lamina X around the central canal. Radioenzyme assays based on the measurement of tritiated water release confirmed the presence of substantial levels of aromatase activity throughout the rostrocaudal extent of the spinal cord. Contrary to what is observed in the brain, this enzyme activity and the number of aromatase-immunoreactive cells in five representative segments of the spinal cord are not different in sexually mature males or females and are not influenced in males by castration with or without testosterone treatment. The aromatase activity and the numbers of aromatase-immunoreactive cells per section are higher at the brachial and thoracic levels than in the cervical and lumbar segments. These experiments demonstrate for the first time the presence of local estrogen production in the spinal cord of a higher vertebrate. This production was localized in the sensory fields of the dorsal horn, where estrogen receptors have been identified previously in several avian and mammalian species, suggesting an implication of aromatase in the modulation of sensory (particularly nociceptive) processes.

Comparison between short-term food restriction and exercise on whole body glucose disposal in high-fat rats

High-fat diets induce whole-body insulin resistance. The aim of this study was to compare effect of two interventions: 3-day food restriction (66% of ad libitum fed) and 3-day exercise training (voluntary running wheels), on decreased insulin-mediated whole body glucose uptake in high-fat fed rats (5 mo old) using the hyperinsulinemic euglycemic clamp procedure. The control group was maintained on rat chow alone. After high-fat feeding for 2 wk, insulin-stimulated whole body glucose utilization was significantly decreased by 26%. The exercise training was more effective than food restriction in lowering plasma concentrations of insulin and triacylglycerol and tissue concentrations of triacylglycerol in soleus muscles. Diminished whole-body glucose uptake resulting from high-fat feeding was reversed completely by exercise training, but only partially by food restriction. The time course of starvation on insulin-stimulated glucose uptake was also observed in high-fat fed rats. Although the extension of starvation time to 48 h resulted in decreased plasma glucose, insulin and triacylglycerol concentrations, whole body glucose uptake did not increase further. These findings suggest that short-term exercise has a higher restorative effect on insulin sensitivity in high-fat fed rats than food restriction, in spite of the same loss in body weight, presumably due in part to improved local lipid availability.

Increase in production of ascorbate radical in tissues of rat treated with paraquat

The production of ascorbate radical (A*-) was investigated in tissues of rats intoxicated with paraquat (PQ) to know the protective role of antioxidant ascorbate (AH-) in tissues. The electron spin resonance (ESR) method is applied to observe A*-. To eliminate increased biosynthesis of ascorbic acid (AH2) by PQ intoxication, ODS rats were chosen and fed with or without 250 ppm PQ in the diet. The radical A*- was detected only in the lung and spleen homogenates of both intoxicated and control rats at the beginning of ESR measurement. The radical levels of intoxicated rat lung and spleen were increased rapidly to twice the initial level after 3 h and decreased to 0.2-0.6 times the initial level after 24 h, whereas those of control rats were increased slowly to 1.1 times the initial level after 4 h and decreased slowly to 0.7 times the initial level after 24 h at 4 degrees C. In other organs such as liver, kidney, heart and testis, A*- was not detected initially but detected afterwards. Higher A*- level was observed in the intoxicated rat liver than the control but no appreciable differences of A*- levels were observed between the intoxicated kidney, heart and testis and the respective controls. In the intoxicated rat lung the concentration of AH2 is only half but that of A*- is twice as high as that of the control. Larger amounts of A*- produced in the intoxicated rats decayed more quickly than those in the control rats. The simple addition of PQ to the control organ enhanced neither A*- production nor A*- quenching. These facts suggest that the tissues damaged by PQ require larger amounts of AH- to detoxicate harmful oxidants, resulting in concomitant production of A*-.

Cellular biological differences between human myeloma cell lines KMS-12-PE and KMS-12-BM established from a single patient

To clarify cellular biological varieties of myeloma cells, biological differences were analyzed between 2 human myeloma cell lines, KMS-12-PE and KMS-12-BM, derived from pleural effusion and bone marrow, respectively, of a single patient. Although both lines were considered to be derived from the same clone because both had the same chromosomal marker and immunoglobulin H rearrangement, several biological differences were noted. CD11a and CD20 were highly expressed in the KMS-12-BM line, whereas the KMS-12-PE line showed a higher expression of CD7 and CD95/Fas. Although growth was stimulated in KMS-12-BM by interleukin-6 and interferon-alpha, it was inhibited in KMS-12-PE. In addition, apoptosis inhibitors Bcl-2 and Bcl-X(L) were highly expressed in KMS-12-BM cells. Because KMS-12-PE was cultivated 2 months before KMS-12-BM, these differences might be related to their origin (pleural effusion and bone marrow) or the phases of disease progression. However, these biological differences may help clarify myeloma cell biology and lead to improvement in treatment for myeloma patients.

Protective effect of melatonin against alpha-naphthylisothiocyanate-induced liver injury in rats

The protective effect of melatonin against alpha-naphthylisothiocyanate (ANIT)-induced liver injury with cholestasis was examined in rats injected once with the toxicant (75 mg/kg body weight (BW)). In rats injected with ANIT alone, liver injury with cholestasis did not occur 12 hr after the injection but appeared at 24 hr, judging from the serum levels of marker enzymes and components. When melatonin (10 or 100 mg/kg BW) was orally administered to the ANIT-injected rats at 12 hr after the injection, the administered indoleamine dose-dependently prevented the formation of liver injury with cholestasis. In rats injected with ANIT alone, serum lipid peroxide (LPO) concentration increased 24 hr after the injection, while liver LPO concentration increased 12 hr after the injection and further increased at 24 hr. Myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration, in the liver of the ANIT-injected rats increased 12 hr after the injection and further increased at 24 hr. The oral administration of melatonin (10 or 100 mg/kg BW) to the ANIT-injected rats attenuated the increases in serum and liver LPO concentrations and liver MPO activity found at 24 hr after the injection in a dose-dependent manner. These results indicate that orally administered melatonin at pharmacological doses protects against ANIT-induced liver injury with cholestasis in rats, and suggest that this protective effect of melatonin could be due to its antioxidant action and its inhibitory action against neutrophil infiltration in the liver of ANIT-injected rats.

Ketamine decreased striatal [(11)C]raclopride binding with no alterations in static dopamine concentrations in the striatal extracellular fluid in the monkey brain: multiparametric PET studies combined with microdialysis analysis

The effects of ketamine, a noncompetitive antagonist of NMDA receptors, on the striatal dopaminergic system were evaluated multiparametrically in the monkey brain using high-resolution positron emission tomography (PET) in combination with microdialysis. L-[beta-(11)C]DOPA, [(11)C]raclopride, and [(11)C]beta-CFT were used to evaluate dopamine synthesis rate, D(2) receptor binding, and transporter availability, respectively, in conscious and ketamine-anesthetized animals. Dopamine concentrations in the striatal extracellular fluid (ECF) were simultaneously measured by PET. Thirty minutes prior to PET scan, intravenous administration of ketamine was started by continuous infusion at a rate of 3 or 10 mg/kg/h. Ketamine infusion dose-dependently decreased [(11)C]raclopride binding, but induced no significant changes in dopamine concentration in the striatal ECF as measured by microdialysis at any dose used. In contrast, ketamine increased both dopamine synthesis and DAT availability as measured by L-[beta-(11)C]DOPA and [(11)C]beta-CFT, respectively, in a dose-dependent manner. These results suggest that the inhibition of glutamatergic neuronal activity modulates dopamine turnover in the striatum by simultaneous enhancement of the dynamics of dopamine synthesis and DAT availability to the same extent, resulting in no apparent changes in ECF dopamine concentration as measured by microdialysis. It also suggests that the alteration of [(11)C]raclopride binding in vivo as measured by PET might not simply be modulated by the static synaptic concentration of dopamine.

[Study of the two-step tuberculin tests and gamma-interferon assays in elderly persons]

Recently, an outbreak of lung tuberculosis among elderly residents happened in the home for aged, and it has become a social problem. To analyze the problem of tuberculosis in the elderly persons, we performed two-step tuberculin tests at two weeks interval and gamma-interferon assays for diagnosis of human tuberculosis to residents in the home for aged. 45 males (age; 77.3 +/- 8.9 SD) and 118 females (age; 81.9 +/- 8.6 SD) elderly persons (> or = 60) were examined. Standard dose of PPD was injected intracutaneously, and read at 48 hours. Erythema of 10 mm diameter or more was considered positive. The results were as follows. (1) The percentages of positive reactors in the 1st (T1) and the 2nd (T2) tuberculin tests were 50.3% and 68.1%, respectively. (2) The diameters of erythema and percentage of positive reactors (T1) did not very with age, but the size of erythema increased from 13.5 mm (T1) to 21.2 mm (T2) among those below 80 years, and from 13.0 mm (T1) to 16.4 mm (T2) among those 80 years or higher (p < 0.01). (3) The percentage of positive reactors (T1) varied by sex, namely males react stronger than females. (4) A dose of interferon-gamma released specifically in response to PPD stimulation of whole blood cultures showed no close relation with the diameters of erythema. In conclusion, tuberculin reactivity waned among elderly persons, and the fact suggests that they would have lower resistance against new infections, and as a result, they might have higher risk of developing tuberculosis. Elderly residents should be performed two-step tuberculin tests at the time of their entrance to the home for aged, and negative reactors should carefully be followed up.

Association of CD44 with OTS-8 in tumor vascular endothelial cells

Endothelial cells in solid tumors play an important role in tumor growth, invasion and metastasis through angiogenesis. We have recently cloned two tumor vascular antigens from isolated rat tumor vascular endothelial cells (TEC). One is CD44, a family of cell surface proteins implicated in adhesion interactions and tumor metastasis. The other is OTS-8, a marker for osteoblast into osteocyte transition and type I alveolar epithelial cells termed as E11 antigen and RTI40, respectively. To test for a possible interaction between the two antigens on endothelial cells in tumor angiogenesis, we examined in vivo association of CD44 with OTS-8 using lysates of isolated rat TEC and COS-7 cells cotransfected with CD44 and OTS-8 expression plasmids. The association was detected by direct co-immunoprecipitation of the two types of cells lysed with digitonin, whereas the detection was lost when lysed with Nonidet P-40. To confirm this association, intact COS-7 cells cotransfected were reacted with homobifunctional N-hydroxysuccinimide ester crosslinking reagents. Immunoblot analysis showed a crosslinked CD44/OTS-8 protein complex of 120 kDa, suggesting the proximity of the two proteins. These findings provide evidence of a weak physical association between CD44 and OTS-8 in TEC, and suggest that OTS-8 may alter the mode of endothelial cell growth and/or migration induced by CD44 in tumor angiogenesis.

Step by step filter based program for calculations of highly informative derivative curves

We have developed a microcomputer program, based on a recently described approach called step by step filter (SBSF), for calculation of derivative curves directly from spectra recorded as a function of wavelength. This program avoids the long wavelength attenuation featured at conventional method for derivative curves calculation, and in this extent could be very helpful for daily spectroscopy practice. The features of the SBSF program include: easy treatment of data through a windowed environment, calculating of both conventional and step by step filter derivatives, possibilities for selection of the mathematical conditions for smoothing and differentiation simultaneous plotting of the original curve and its derivative and a mouse pointer. Several examples from different branches of the molecular spectroscopy (absorption UV-VIS, CD and fluorescence) are provided and discussed in the terms of advantages of SBSF.

Endosonographic probe-guided endoscopic removal of colonic pedunculated leiomyoma

We report a rare case of endoscopic removal of colonic pedunculated leiomyoma with an aid of endoscopic ultrasonography (EUS). A 46-year-old man was admitted to our hospital with complaints of lower abdominal pain and alternating constipation and diarrhea. Colonoscopy revealed a small pedunculated polyp in the transverse colon covered with almost normal mucosa. EUS showed a hypoechoic solid tumor with clear margins and smooth contour in the second to third layer. We considered this lesion as a submucosal tumor of the colon with no continuity to the muscularis propria. We performed endoscopic removal of this tumor successfully, and histological diagnosis was a leiomyoma. Endoscopic removal of colonic pedunculated leiomyoma is rare. Moreover, in our case, EUS showed typical findings of colonic leiomyoma and was useful to assess the location of the submucosal tumor. We describe herein our experience and discuss similar cases reported in the English literature.