Ureteral fibroepithelial polyp associated with urolithiasis induced by steroid therapy in a child: a case report

A 14-year-old boy complained of left flank pain. He had been given high-dose corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIDP). Retrograde pyelography revealed irregular defects at the left ureteropelvic junction (UPJ), and ureteroscopy demonstrated ureteral polyp. The polyp was removed and histologically diagnosed as fibroepithelial polyp. Hypercalciuria due to the corticosteroids and bedridden was assumed to have been a causative factor in the stone formation. To our knowledge, this is the first report of a ureteral fibroepithelial polyp in children associated with urolithiasis, and associated with CIDP.

Entactin-induced inhibition of human amyloid beta-protein fibril formation in vitro

Amyloid beta-protein (Abeta) fibril in senile plaques may possibly be related to the pathogenesis of Alzheimer's disease (AD). Basement membrane (BM) components are localized to the plaques. Entactin binds the plaque associated BM components. We investigated the potential of entactin to prevent Abeta fibril formation. Thioflavin T fluorometric assay and electron microscopy revealed that entactin significantly inhibited Abeta1-40 (Abeta40) fibril formation at an Abeta40:entactin molar ratio of 50:1. The inhibitory effect of entactin was displayed in a dose-dependent manner. Circular dichroism spectroscopy data indicated that entactin induced a random coil structure in Abeta40. We propose that the ability of entactin to induce random structure is linked to the inhibition of Abeta fibril formation. Entactin may be related to the pathogenesis of AD by regulating Abeta40 fibril formation.

Pharmacological characterization of a novel 5-HT4 receptor agonist, TS-951, in vitro

The pharmacological effect of a novel selective 5-HT4 receptor agonist, TS-951 (N-[endo-8-(3-hydroxypropyl)-8-azabicyclo[3.2.1]oct-3-yl]-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide) was investigated in vitro. TS-951 potently inhibited specific [3H]GR113808 binding both in guinea-pig striatum and in mouse brain. The affinity of TS-951 for the 5-HT4 receptor was higher than those of other agonists, 5-HT, cisapride, mosapride and renzapride. On the longitudinal muscle of the guinea-pig ileum, TS-951 caused a concentration-dependent increase in the amplitude of electrically induced submaximal twitch contractions. On the longitudinal muscle of the guinea-pig distal colon, TS-951 also caused concentration-dependent contractions. TS-951 is a high-affinity, selective and potent 5-HT4 receptor agonist. This compound therefore can be considered as a useful pharmacological tool for investigating 5-HT4 receptor-mediated events.

Properties of an extracellular polysaccharide produced by a strain of enterobacter isolated from pond water

A bacterium which was isolated from pond water and identified as Enterobacter cloacae produced a viscous extracellular polysaccharide when it was grown aerobically in a medium containing sucrose as a sole source of carbon. The maximum molecular weight of the polysaccharide was about 9.0 x 10(5). The polysaccharide was composed of fucose, galactose, glucose, and glucuronic acid in a molar ratio of 2:3:2:1, but the molecular weight and the molar ratio of the sugar component were different from those of the polysaccharide produced by the same species reported elsewhere.

β-amyloid induces caspase-dependent early neurotoxic change in PC12 cells: correlation with H2O2 neurotoxicity

We examined neurotoxic effects of Abeta(25-35), an active fragment of beta-amyloid (Abeta), and compared the effect with H2O2 neurotoxicity in PC12 cells. Abeta(25-35) induced the loss of mitochondria function as detected using a tetrazolium salt (WST-1) reduction assay and decreased the number of cells adhering to collagen type 1-coated plates. Abeta(25-35) did not induce cell death, as detected by Hoechst 33342/propidium iodide staining. The caspase tetrapeptide inhibitor z-IETD-fluoromethylketone (FMK) and z-LEHD-FMK inhibited the attenuation of WST-1 reduction induced by Abeta(25-35) and H2O2, while the caspase-3 inhibitor z-DEVD-FMK afforded protection only against H2O2 neurotoxicity. Caspase-3 protease activity was increased by treatment of H2O2 but not Abeta(25-35). Thus, Abeta(25-35) induces early neurotoxic events by activating caspases other than caspase-3. H2O2 -induced oxidative stress may not be implicated in Abeta-induced neurotoxic pathways.

Circadian rhythm of drinking and running-wheel activity in rats with 6-hydroxydopamine lesions of the ventral tegmental area

Circadian rhythms in drinking and running-wheel (locomotor) activity of rats with 6-hydroxydopamine (6-OHDA, 4 microg/2 microl per rat)-induced lesions in the ventral tegmental area (VTA) were examined under a light-dark (LD) cycle and constant dim light (5 lux). Under the LD cycle, the length of the locomotor activity period was decreased during the dark, and increased during the light period in the lesioned rats. Under the constant dim light conditions, the free-running circadian period (tau) of drinking and activity rhythm was longer in lesioned rats than in sham-operated controls. The elongation of the circadian period was accompanied by decrements in activity. These observations suggest that the mesolimbic dopaminergic system modulates rhythms in circadian drinking and locomotor activity.

Improving the freeze tolerance of bakers' yeast by loading with trehalose

We examined the freeze tolerance of bakers' yeast loaded with exogenous trehalose. Freeze-tolerant and freeze-sensitive compressed bakers' yeast samples were soaked at several temperatures in 0.5 M and 1 M trehalose and analyzed. The intracellular trehalose contents in both types of bakers' yeast increased with increasing soaking period. The initial trehalose-accumulation rate increased with increasing exogenous trehalose concentration and soaking temperature. The maximum trehalose content was almost identical (200-250 mg/g of dry cells) irrespective of the soaking temperature and the type of bakers' yeast, but depended on the exogenous trehalose concentration. The leavening ability of both types of bakers' yeast loaded with trehalose was almost identical to that of the respective original cells, irrespective of the soaking conditions. The freeze-tolerant ratio (FTR) of both types of bakers' yeast increased with increasing intracellular trehalose content. However, FTR decreased during over-soaking after the maximum amount of trehalose had accumulated. FTR of the freeze-sensitive bakers' yeast was more efficiently improved than that of the freeze-tolerant type.

Structure-activity relationships of quinazoline derivatives: dual-acting compounds with inhibitory activities toward both TNF-alpha production and T cell proliferation

We synthesized 4-chlorophenethylaminoquinazoline derivatives and evaluated their inhibitory activities toward both TNF-alpha production and T cell proliferation responses. Compound 2f, containing a piperazine ring at the C(7)-position of the quinazoline ring, exhibited more potent inhibitory activities toward both than the lead compound la. A smaller N-substituent in the piperazine ring was required for inhibition of TNF-alpha production.

Synthesis and structure-activity relationship of diarylamide derivatives as selective inhibitors of the proliferation of human coronary artery smooth muscle cells

A series of diarylamide derivatives were synthesized and evaluated for their inhibitory activities against human coronary artery smooth muscle cells (SMCs) and human coronary artery endothelial cells (ECs). Compound 2w was superior to the lead compound, Tranilast, in terms of the potency of the activity and cell selectivity.

Effects of 5-HT(4) receptor agonist prokinetic agents on the action potential parameters of isolated rabbit myocardium

The effects of TS-951, a novel gastrointestinal prokinetic agent with 5-HT(4) receptor agonistic action, on the action potential parameters of isolated rabbit Purkinje fiber, ventricular muscle and sinoatrial node, and on the spontaneously beating rates of isolated rabbit right atria were compared with those of cisapride. TS-951 had no effect on the action potential parameters in both rabbit Purkinje fiber and ventricular muscle preparations. However, cisapride significantly prolonged action potential duration (APD) in both preparations. Both TS-951 and cisapride produced a negative chronotropic effect in rabbit right atria; TS-951 and cisapride at 3 x 10(-5) mol/l reduced the beating rate by about 20 and 40%, respectively. In the sinoatrial node preparations, TS-951 (3 x 10(-5) mol/l) as well as cisapride (10(-6) mol/l) prolonged cycle length and APD and reduced the diastolic depolarization rate. These results indicate that TS-951 does not appear to possess electrophysiological features leading to cardiotoxicity such as QT prolongation and, thus, torsades de pointes in common with cisapride.

Melatonin inhibits Arg-vasopressin release via MT(2) receptor in the suprachiasmatic nucleus-slice culture of rats

The effect of melatonin on the release of Arg-vasopressin (AVP) was analyzed in a suprachiasmatic nucleus-slice explant culture. The release of AVP into the culture medium exhibited a circadian rhythm, with higher level during the subjective day and lower level during the subjective night. Melatonin (500 nM) inhibited the release of AVP. Luzindole, a MT(2) (Mel 1b) melatonin receptor antagonist, attenuated the effect of melatonin on the AVP release. Results indicate that the inhibition of AVP release by melatonin in the suprachiasmatic nucleus-slice culture depends at least in part on the melatonin MT(2) receptor.

Synthesis and evaluation of novel 2-oxo-1,2-dihydro-3-quinolinecarboxamide derivatives as potent and selective serotonin 5-HT4 receptor agonists

A series of 8'-substituted N-(endo-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamides were synthesized. The 5-HT4 receptor agonistic activity was evaluated using the isolated guinea pig ileum preparation. Of the compounds synthesized, N-(endo-8-(3-hydroxypropyl)-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (15a, TS-951) exhibited the most potent serotonin 5-HT4 receptor agonistic activity. This compound had a high affinity for the serotonin 5-HT4 receptor although it had no affinities for other broad spectrum receptors. Furthermore, it remarkably enhanced gastrointestinal motility in conscious fed dogs without unfavorable effects that non-selective serotonin 5-HT4 receptor agonist has. TS-951 may be useful in improving gastrointestinal dysfunction.

Laparoscopic-assisted hepatectomy (LAH) for the treatment of hepatocellular carcinoma

The treatment of hepatocellular carcinoma associated with liver cirrhosis necessitates local therapy in some patients because of severe hepatic dysfunction. Percutaneous ethanol injection therapy, the local therapy for such cancer of the liver, and percutaneous microwave coagulation therapy are detailed. The significant disadvantages of these procedures is their inability to evaluate precisely whether the tumor will develop complete necrosis after treatment because the cancer tissue cannot be excised with use of these procedures. Conversely, laparoscopic hepatectomy, which is minimally invasive surgery, has a disadvantage, that is, its difficulty in complex maneuvers, including hemostasis, ligation, and suture. The authors developed laparoscopic-assisted hepatectomy, which is hepatectomy by small incision during laparotomy with the use of laparoscopic observation. This report describes laparoscopic-assisted hepatectomy, which may allow the solving of problems with percutaneous ethanol injection therapy, percutaneous microwave coagulation therapy, and laparoscopic hepatectomy.

Synthesis and evaluation of novel 2-oxo-1,2-dihydro-3-quinolinecarboxamide derivatives as serotonin 5-HT4 receptor agonists

A series of N-azabicycloalkyl-1-alkyl-2-oxo-1,2-dihydro-3-quinolinecarboxamides were synthesized and tested for serotonin 5-HT4 receptor-stimulating effects in the regulation of electrically-evoked contraction in guinea pig muscle. Among them, N-azabicycloalkyl-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (8c, 9c, 10c, 11c, 12c) exhibited potent serotonin 5-HT4 receptor-stimulating activity. The most potent compound, N-(endo-8-methyl-8-azabicyclo[3.2.1 oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (8c, ED50 = 36.3 nMi), was seven times as active as cisapride, while 8c had no affinity for 5-HT1A, 5-HT1D, D2, muscarinic M2 or muscarinic M3 receptors even at 10 microM. Compound 8c stimulated digestive tract motility in conscious fed dogs (1.0 mg/kg p.o.).

Synthesis and biological evaluation of CX-659S and its related compounds for their inhibitory effects on the delayed-type hypersensitivity reaction

In order to find novel nonsteroidal compounds possessing an inhibitory activity against delayed-type hypersensitivity (DTH) reactions, we conducted random screening using a picryl chloride (PC)-induced contact hypersensitivity reaction (CHR) in mice, and found compound 1 as a lead compound. Then we synthesized and evaluated an extensive series of 5-carboxamidouracil derivatives focused on both the uracil and the antioxidative moieties. Among them, we found that the hindered phenol moiety was necessary to exhibit the activities; especially, compounds 28a-28c having the partial structure of vitamin E were found to exert potent activities against the DTH reaction by both oral and topical administration. And compound 28c showed antioxidative activity against lipid peroxidation with an IC50 of 5.9 microM. Compound 28c (CX-659S) was chosen as a candidate drug for the treatment of cutaneous disorders such as atopic dermatitis and allergic contact dermatitis.

[CD8-positive diffuse large B-cell lymphoma]

In May, 1998, a 63-year-old woman was admitted for treatment of relapsed malignant lymphoma. In March 1997, a diagnosis of diffuse large B-cell lymphoma(DLBL), clinical stage IIISE A, was made from a biopsy specimen of the tumor in the left buccal mucosa. Six cycles of CHOP regimen were given, and complete remission was achieved. However, relapse of the lymphoma was suspected, and the patient was transferred to our hospital. On admission, a right tosillar mass, 8 mm in diameter, was found, and a biopsy showed DLBL. The immunophenotype of the lymphoma cells was CD3- CD4- CD5- CD8+ CD10- CD19+ CD20+ CD23- CD25+ IgL (lambda)+, and dual staining confirmed that the cells were CD8+ and CD19+. The patient was an HTLV-1 carrier, but monoclonal integration of HTLV-1 proviral DNA into the lymphoma cells was not detected. She was diagnosed as having CD8+ DLBL, clinical stage IA. Because she responded to salvage chemotherapy, autologous peripheral blood stem cell transplantation was performed and complete remission was obtained. To our knowledge, this is the first report of CD8+ DLBL.

Rat epididymal sperm motion changes induced by ethylene glycol monoethyl ether, sulfasalazine, and 2,5-hexandione

Epididymal sperm was examined using the Hamilton-Thorne Sperm analyzer (HTM-IVOS, version 10.6) in male rats treated with known male reproductive toxicants that act by different mechanisms to detect effects on sperm motion. Three agents known to produce changes in sperm motion at high exposure levels were administered at lower levels. Ethylene glycol monoethyl ether (EGEE), sulfasalazine (SASP), and 2,5-hexandione (2,5-HD) were administered by oral gavage to adult male Sprague-Dawley rats at 250 or 500 mg/kg/day, at 300 or 600 mg/kg/day, or at 100 or 250 mg/kg/day, respectively. The males were treated with EGEE, SASP, and 2,5-HD for 35, 28, and 28 days, respectively. The males treated with EGEE and SASP were mated with untreated females to assess male fertility. All males were examined for body weight, testicular and epididymal weight, epididymal sperm count, and sperm motion. The sperm motion parameters included percentage of motile sperm, percentage of progressively motile sperm (progressive motility), curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (VSL), amplitude of lateral head displacement (ALH), beat cross frequency (BCF), linearity (LIN), and straightness (STR). For the male rats treated with SASP, no treatment-related effects on percentages of motile sperm or sperm count were observed despite impaired male fertility. However, abnormal motion of epididymal sperm from the SASP treated males was detected by a significant reduction in mean progressive motility, VAP, and ALH, and an increase in BCF and STR. For the males treated with 2,5-HD for 4 weeks, most parameters generated by the HTM-IVOS indicated decreased sperm motion despite no remarkable changes in testicular weight, epididymal weight, or sperm count. In the EGEE-treated males at 250 mg/kg/day for 5 weeks, abnormal motion of epididymal sperm was detected by decreased progressive motility and increased BCF, although there were no treatment-related effects on testicular weight or male fertility. Progressive motility was decreased in all treated groups and the difference from the control value was of the greatest magnitude among the sperm motion parameters generated by the HTM-IVOS. Velocity parameters (VAP, VSL, VCL) responded sensitively to abnormal sperm motion in the SASP and 2,5-HD studies. In spite of decreased sperm motion, BCF values were significantly increased in all treated groups except the 7-week EGEE high-dose group, where there were no motile sperm to evaluate. ALH was significantly decreased in the treated groups in which remarkable effects on sperm motion were noted. There were no significant changes in ALH at the low-dose of EGEE at which only mild effects on sperm motion were observed. STR was increased for epididymal sperm from the males treated with SASP when compared with the controls. For the males treated with EGEE and 2,5-HD, however, STR was decreased when compared with the controls. There were no significant differences in LIN in any of the groups treated with SASP, in which remarkably reduced sperm motion was detected by the other parameters. In conclusion, among the parameters generated by the HTM-IVOS, progressive motility was significantly decreased in all treated groups and the most valuable for detecting slight changes in sperm motion induced by these three different target toxicants. Further investigation with a larger set of compounds is needed to evaluate which IVOS parameters are the most sensitive in detecting motion changes.

Distribution of Helicobacter pylori in a Mongolian gerbil gastric ulcer model

BACKGROUND AND PURPOSE

To the authors' knowledge, histopathologic changes associated with early H. pylori infection and ulceration have not been established. We examined presence of H. pylori infection in an acetic acid-induced gastric ulcer (AAU) model in Mongolian gerbils.

METHODS

Sixty Mongolian gerbils were used as an AAU model, and another 60 gerbils were studied as a control (non-AAU) group. All animals were orally administered H. pylori, then were evaluated by use of histologic and bacteriologic examinations.

RESULTS

Helicobacter pylori were scattered on the surface mucous gel layer and in the pyloric gland gastric were pits; inflammation seen at the early stages later extended to the mucosa of the fundic gland area. The organisms were predominantly observed in the AAU model, but findings were comparable to those in controls at 1, 3, 7, 14, 28, or 56 days. Evaluation with regard to viable bacterial numbers reflected the histologic aspects, that the pyloric gland area had more viable counts than did the fundic gland area. Carbohydrate composition of mucin differed between pyloric and fundic gland areas. These findings shed light on L-fucose related to the H. pylori adhesive factor abundant in mucin of the pyloric gland area.

CONCLUSIONS

Findings for this ulcer model of Helicobacter pylori infection make it useful for the study of onset of infection and screening of anti-ulcer agents.

Up-regulation of telomerase in primary cultured rat hepatocytes

Telomerase is a unique reverse transcriptase involved in the maintenance of telomeric DNA, which is generally undetectable in normal human somatic cells. However, it has been found in organs of normal adult rodents including the liver. In order to elucidate relevant control mechanisms operating in normal somatic cells, we examined telomerase activity in primary cultured rat hepatocytes. During culture under serum-free conditions, rat hepatocytes rapidly lose the ability of organ-specific expression of serum albumin, apolipoprotein A-I, and hepatocyte nuclear factor 4, and the capacity for cytochrome P-450 induction by xenobiotics. The telomerase activity was found to be concomitantly increased about 2. 5-fold at 48 h and 3-fold at 72 h. Northern blot and RT-PCR analyses with primary cultured hepatocytes revealed the associated accumulation of rat telomerase RNA subunits (TR), and the mRNAs for a telomerase reverse transcriptase (TERT) and a telomerase-associated protein (TEP1). The activity of hepatocyte telomerase, which was elevated during the primary culture, increased further when the cells were stimulated with hepatocyte growth factor. In this case, however, the levels of TR, TERT, and TEP1 mRNA did not show any detectable changes.