G1 phase arrest induced by Wilms tumor protein WT1 is abrogated by cyclin/CDK complexes

WT1, the Wilms tumor-suppressor gene, maps to the human chromosomal region 11p13 and encodes a transcriptional repressor, WT1, implicated in controlling normal urogenital development. Microinjection of the WT1 cDNA into quiescent cells or cells in early to mid G1 phase blocked serum-induced cell cycle progression into S phase. The activity of WT1 varied significantly depending on the presence or absence of an alternatively spliced region located upstream of the zinc finger domain. The inhibitory activity of WT1 was abrogated by the overexpression of cyclin E/CDK2 as well as cyclin D1/CDK4. Furthermore, both CDK4- and CDK2-associated kinase activities were downregulated in cells overexpressing WT1, whereas the levels of CDK4, CDK2, and cyclin D1 expression were unchanged. These findings suggest that inhibition of the activity of cyclin/CDK complexes may be involved in mediating the WT1-induced cell cycle block.

Effects of tetraprenylacetone on pancreatic exocrine secretion and acute pancreatitis in two experimental models in rats

The effects of tetraprenylacetone (TPN), an acyclic polyisoprenoid with antiulcer actions, on pancreatic exocrine secretion, and its preventive and therapeutic effects on acute pancreatitis in two experimental models were studied in rats. Intraduodenal administration of TPN (0, 100, 200, and 400 mg/kg/h) caused dose-dependent increases in pancreatic juice and bicarbonate output without increasing protein output and plasma cholecystokinin (CCK) concentrations. TPN-stimulated pancreatic exocrine secretion was completely abolished by antisecretin serum but it was not by CCK receptor antagonist loxiglumide (50 mg/kg/h). In acute pancreatitis induced by four subcutaneous injections of 20 micrograms/kg cerulein at hourly intervals over, 3 h, TPN (400 mg/kg) given by an oral route either 1 h before the first cerulein injection or immediately after the last injection significantly reduced the increases in serum amylase and lipase activities and pancreatic wet wt. Pretreatment with TPN caused histologic improvements, whereas posttreatment failed to ameliorate histologic alterations. In severe type of acute pancreatitis induced by retrograde intraductal injection of 1.0 mL/kg of 4% sodium taurocholate, TPN exerted no apparent beneficial effects on biochemical and histologic alterations of acute pancreatitis. It is concluded that TPN given by an oral route stimulates pancreatic exocrine secretion through an increase in endogenous secretin release and causes beneficial effects on the experimental model of mild acute pancreatitis in rats.

The Tidal Rhythm of Emergence, and the Seasonal Variation of This Synchrony, in an Intertidal Midge

The emergence of an intertial midge was investigated at a site on the coast of the Inland Sea of Japan. The population emerging at this site was drawn from a single species of the genus Clunio, probably C. tsushimensis. Emergence was not synchronized with the day-night cycle, but with the tidal cycle. Moreover, the pattern of synchrony changed with season. A bimodal phase appeared in midwinter; but the pattern of synchrony shifted gradually, during January and February, from morning low tides to afternoon low tides, and a unimodal phase appeared in March. This pattern--i.e., synchrony with afternoon low tides--lasted until early October. In mid-October, the synchrony shifted to the morning low tides. Only a brief bimodal phase appeared in autumn. The phase modality was clearly correlated with the height of tides; i.e., when the low waters in a day were very different in height, emergence was synchronized only with the lower one (April to December). During January and February, the higher low tide, as well as the lower low tide, recedes considerably. The exposure of the larval habitat at the higher low tide may stimulate emergence, resulting in bimodal phases in midwinter. But the unimodal pattern in March cannot be accounted for by a simple synchrony with lower low tide, or with exposure of the larval habitat to the air; the day-night cycle not only would be one of the zeitgebers of the tidal rhythm in every season, but also must participate in the expression of the unimodal phase in spring. Furthermore, the number of midges that emerged each day fluctuated with a semilunar cycle with the season. The phase of this rhythm would be shifted by water temperature.

Loss of sensitivity to cholecystokinin stimulation of isolated pancreatic acini from genetically diabetic rats

Pancreatic exocrine function of a new inbred strain Otsuka Long-Evans Tokushima Fatty (OLETF) rat that develops spontaneous persistent hyperglycemia was evaluated in in vitro isolated pancreatic acini and compared with that in the control Long-Evans Tokushima Otsuka (LETO) rat. Serum glucose and insulin concentrations in the OLETF rats were significantly high (glucose: 270 +/- 12 vs. 208 +/- 10 mg/100 ml, P < 0.01; insulin: 12.4 +/- 1.7 vs. 4.9 +/- 0.6 ng/ml, P) < 0.01), whereas pancreatic wet weight was significantly low (803 +/- 20 vs. 1,138 +/- 17 mg, P < 0.01) compared with those in the LETO rat. Pancreatic acini isolated from the OLETF rat were totally insensitive to cholecystokinin (CCK)-8 stimulation at concentrations of up to 100 nM. However, neither the responsiveness nor the sensitivity to carbamylcholine, bombesin, and secretin of the acini from the OLETF rat was altered or even increased, probably due to the larger amylase content in the OLETF rat acini compared with those of the LETO rat acini (31.5 +/- 2.0 vs. 13.0 +/- 1.1 Somogyi units/micrograms DNA, P < 0.01). The responsiveness to fluoride, a direct activator of guanine nucleotide-binding protein, in the OLETF rat acini was similar to that in the LETO rat, suggesting that the transmembrane signaling and effectors and subsequent intracellular signal transduction molecules in the OLETF rat acini are normal. Moreover, 125I-CCK binding to the acini prepared from the OLETF rat was totally absent. These present results indicate that the OLETF rat has a selective defect in the binding of CCK to its receptors on the acinar cell surface.

Identification of endo-beta-N-acetylglucosaminidase and N-acetylmuramyl-L-alanine amidase as cluster-dispersing enzymes in Staphylococcus aureus

Two proteins which are capable of dispersing cell clusters of Staphylococcus aureus have been purified from a S. aureus FDA209P culture supernatant. Both of them were found to have bacteriolytic activity. From the elution profile of column chromatography and Western blot (immunoblot) analysis, one of them was identified as a 51-kDa endo-beta-N-acetylglucosaminidase (GL). The other was a 62-kDa protein on the basis of sodium dodecyl sulfate gel electrophoresis. Analysis of the peptidoglycan fragments following treatment with the 62-kDa protein indicated that this protein is an N-acetylmuramyl-L-alanine amidase (AM). In vitro studies of cluster dispersion activities using S. aureus mutant strains Lyt66 or S. aureus Wood46 grown as clusters demonstrated that these two enzymes act synergistically to disperse clusters into single cells. Antiserum against the 51-kDa GL cross-reacted with the 62-kDa AM, and S. aureus FDA209P grown in the presence of anti-51-kDa-GL immunoglobulin G induced giant clusters. Clusters induced by anti-51-kDa GL and by Cibacron blue F3G-A were dispersed by coincubation with the 51-kDa GL and the 62-kDa AM. Western blot analysis demonstrated that the 51-kDa GL and the 62-kDa AM were missing in culture supernatants of S. aureus Lyt66, Wood46, and RUSAL2 (Tn551 autolysin-defective mutant), which grow in clusters. These results strongly suggest that the 51-kDa GL and 62-kDa AM are involved in cell separation of daughter cells after cell division.

Stability and pharmacokinetic characteristics of oligonucleotides modified at terminal linkages in mice

To construct the strategy for delivery systems that can control in vivo disposition of antisense oligonucleotides, we studied the stability and basic pharmacokinetic characteristics of oligonucleotides. Decathymidylic acid (T10), a model oligodeoxynucleotide, and its derivatives, 5'-biotin-T10) and 3'-methoxyethylamine 5'-biotin-T10 (3'M5'B-T10), containing phosphoroamidate modification at 3'- and/or 5'-terminal internucleoside linkages, were synthesized. In phosphate-buffered saline (PBS, pH 7.4) containing 10% mouse serum, unmodified T10 was degraded with a half-life of 45 minutes; the degradation half-lives of 5'B-T10 and 3'M5'B-T10 were 11 and 30 h, respectively. In mouse whole blood, 3'M5'B-T10 was relatively stable, and 45% remained intact after 1 h incubation. After intravenous injection of [3H]3'M5'B-T10 into mice at a dose of 1 mg/kg, the radioactivity was rapidly cleared from plasma with a half-life of 2 minutes and accumulated in the kidney, liver, and gallbladder. About 30% of the dose was excreted in the urine within 60 minutes. A much more rapid degradation of [3H]3'M5'B-T10 was observed in vivo than expected from in vitro experiments: more than 90% of the radioactivity in plasma was degradation product at 2 minutes after injection. These results suggested that enzymatic degradation occurred in some compartments in addition to the blood pool. The apparent urinary excretion clearance of [3H]3'M5'B-T10 was close to that of inulin, whereas the apparent hepatic uptake clearance was much greater than that of inulin and comparable to that of dextran sulfate, which is taken up by the liver by scavenger receptors for polyanions.(ABSTRACT TRUNCATED AT 250 WORDS)

Block by apomorphine of acetylcholine receptor channels expressed in Xenopus oocytes

Effects of apomorphine and other compounds related to dopamine receptors on nicotinic acetylcholine receptor channels were investigated by expressing functional channels in Xenopus oocytes. When channels were expressed with a combination of alpha 3 and beta 4 subunits, acetylcholine activated an inward current, and apomorphine suppressed the current in a concentration-dependent manner with an IC50 value of about 3 microM. SKF38393 (R(+)-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol; dopamine D1 receptor agonist; 3 and 30 microM), quinpirole (dopamine D2 receptor agonist; 30 microM), SCH23390 (R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benza zepine; dopamine D1 receptor antagonist; 10 microM) or sulpiride (dopamine D2 receptor antagonist; 10 microM) also inhibited the acetylcholine-activated current whereas dopamine (100 microM) was ineffective. The inhibition by apomorphine of the acetylcholine-activated current was also apparent when alpha 3 subunit was combined with beta 2 subunit instead of beta 4 subunit, or beta 4 subunit was combined with alpha 2 or alpha 4 subunit instead of alpha 3 subunit to express channels. The results suggest that apomorphine blocks acetylcholine receptor channels through a binding site that is similar to, but cannot be included in dopamine receptors. The binding site may not be present in a single specific subunit.

Variable loading cholangiomanometry and clinical applications

We have designed a variable loading cholangiomanometric method, which permits a precise and objective evaluation of distal bile duct function. Normal resistance (R) values (1-7 units) and residual pressure (P) values (50-150 mm H2O) have been defined by this method. We have performed this procedure on 138 patients with cholelithiasis, and have found that 13 patients with cholecystolithiasis and 14 patients with choledocholithiasis have elevated R and P values in the distal bile duct. These patients also had morphological abnormalities in the distal bile duct. There was a high percentage of patients with abnormal pressure/flow curves at high flow rates among patients with morphologically dilated bile ducts. Division of pressure/flow curve patterns at low flow rates into three types made it possible to differentiate between functional and structural abnormalities. Patients in whom the residual P values were high and morphological defects of the distal bile duct. The possible application of these measurements in determining the need for additional surgery on the inferior bile duct, particularly papilloplasty, is discussed.

Tissue-specific expression of mouse tyrosinase gene in cultured chicken cells

A mouse tyrosinase cDNA has been combined with different promoters and inserted into several replication-competent avian leukosis proviruses and the viruses were transferred into cultured albino chick cells by viral infection. Expression of the tyrosinase gene depended on one of four promoter sequences: the resident constitutive promoter (Rous sarcoma virus long-terminal repeat; RSV-LTR), 471 bp from the mouse tyrosinase gene-associated promoter, 519 bp from the Japanese quail tyrosinase gene associated promoter, or 369 bp from the quail tyrosinase promoter. The infected cells expressed tyrosinase and produced pigment which could be seen with the light microscope. Immunofluorescence microscopy, using an anti mouse tyrosinase T1-specific antibody, also showed the presence of mouse tyrosinase. When infected with the same viral titer, gene expression was highest with the constitutive LTR promoter. The quail tyrosinase promoter, while less efficient than the LTR, was more efficient than the other tyrosinase promoter. Fibroblasts and hepatocytes infected with the construct carrying the constitutive promoter or the truncated quail promoter expressed tyrosinase. The mouse and quail promoters appeared to show tissue-specific expression since fibroblasts and hepatocytes infected with viruses carrying these promoters did not express mouse tyrosinase. Toxicity is associated with constitutive expression of tyrosinase in nonmelanocytes. Therefore the viruses that carry the tissue specific promoters should be useful for in vivo studies.

[Two cases of hepatic metastasis of colorectal cancer treated effectively by intrahepatic arterial infusion immunotherapy using OK-432, rIL-2, MMC and 5-FU]

Two cases of hepatic metastasis of colorectal cancer were treated effectively by intrahepatic-arterial infusion immunotherapy using OK-432 (2 KE/week or 2 weeks), recombinant IL-2 (35 x 10(4) JRU or 40 x 10(4) JRU/week or 2 weeks), MMC (4 mg/week or 2 weeks) and 5-FU (250 mg/day during admission, 250 mg/week or 2 weeks during outpatient treatment). The levels of CEA were decreased from 17.2 ng/ml to 2.4 ng/ml after 8 weeks in the first case (50 y. o. male) and from 521 ng/ml to 66 ng/ml after 8 weeks in the second case (36 y. o. female), respectively. Abdominal CT revealed a partial response for 11 months in the first case and 6.5 months in the second case.

[Methotrexate/5-fluorouracil therapy in gastric cancer with peritoneal metastasis]

Eighteen patients with gastric cancer with peritoneal metastasis were treated with methotrexate/5-fluorouracil sequential therapy. In four patients, a partial response was obtained and in another four, symptomatic relief was obtained by the therapy. As side effects, BM suppression was seen in 9 and GI symptoms in 6 patients. Intraaortic, low-dose and 3-hour-interval procedure are recommended in the therapy.

[Clinical study of TZP-4238 on patients with benign prostatic hypertrophy--with special reference to urodynamics]

Twenty four cases of benign hypertrophy with bladder outlet obstruction were treated with 17 alpha-acetoxy-6-chloro-2-oxa-4,6-pregnadiene-3,20-dione (TZP-4238), and the effects on urodynamic parameters, clinical efficacy, safety, and usefulness were evaluated. Improvement rate of subjective rate of subjective symptoms was 52.9%. Obstructive symptoms improved more prominently than irritation symptoms. A significant improvement in flow rate of nomograms for maximum flow rate (MFR) and average flow rate (AFR) accompanied with the decrease in the prostatic weight were observed. However, no changes were observed on the urethral sphincter electromyography and the urethral pressure profile. A significant decrease of maximum cystometric capacity was observed, although the effective cystometric capacity was not changed. The overall improvement rate for urodynamic parameters was 43.7%. A significant decrease in weight and diameter of the prostate was observed. The prostatic weight decreased in 57.1%, and the average reduction rate was 15.4%. The overall improvement rate concerning clinical efficacy evaluating both subjective symptoms and objective parameters was 58.8%. Adverse reactions were observed in 5 cases. They were judged as not clinically problematic. Taking into account clinical safety and clinical efficacy, the clinical usefulness was 50.0%. TZP-4238 was considered to be an appropriate agent for treating patients with benign prostatic hypertrophy with bladder outlet obstruction.

Recurrence of intrahepatic stones after an end-to-side choledochojejunostomy

The risk factors for the recurrence of intrahepatic stones after an end-to-side choledochojejunostomy were investigated, along with the outcome following the treatment of such stones. Thirty-two patients with intrahepatic stones underwent an end-to-side choledochojejunostomy, and a complete lithotomy was achieved in 26 of them. The follow-up which ranged from 5-19 years after surgery revealed that eight patients developed a recurrence of intrahepatic stones, and their clinical and cholangiographic findings were thus reviewed. Recurrent stones were associated with onset of symptoms at a younger age and were predominantly located in the intrahepatic bile ducts. Recurrence was also associated with severe intrahepatic bile duct dilatation. Six of the eight patients developed recurrent stones more than 5 years after a complete lithotomy. One of these patients died of liver cirrhosis while two died of acute obstructive suppurative cholangitis. Five patients underwent cholangioscopic lithotomy through the jejunostomy for their recurrent stones, and a complete lithotomy was accomplished in three of them. These findings indicate the necessity of performing a hepatectomy in such patients whenever possible, and also emphasize the need for a long-term follow-up after a complete lithotomy with an end-to-side choledochojejunostomy. In addition, any recurrent stones should be treated promptly by a cholangioscopic lithotomy through a jejunostomy.

Increase in myocardial interstitial norepinephrine during a short period of coronary occlusion

The neurally intact in vivo beating hearts of cats were used to examine the influence of a short period of coronary occlusion on regional myocardial norepinephrine levels. Using a cardiac dialysis technique, dialysate norepinephrine levels were measured as an index of myocardial interstitial norepinephrine levels, and the left anterior descending coronary artery was occluded for 10 min. In anesthetized cats, 10 min occlusion increased the dialysate norepinephrine level in the ischemic region but not in the non-ischemic region. To investigate the influence of neuronal norepinephrine uptake on occlusion-induced dialysate norepinephrine response, a neuronal uptake inhibitor (desipramine) was locally administered to both regions with the dialysis perfusate. In the ischemic region, 10 min occlusion significantly increased the dialysate norepinephrine level from the control level in the presence of desipramine. We concluded that 10 min coronary occlusion was associated with an increase in the myocardial interstitial norepinephrine level in the ischemic region. This increase in the early phase of ischemia was not attributed to attenuation of neuronal norepinephrine uptake function.

Antiarrhythmic agents in older patients. Current state of knowledge

The treatment of ventricular arrhythmias in the elderly population is a challenging problem. Elderly patients are more predisposed to arrhythmias, are less responsive to antiarrhythmic agents and are more susceptible to the adverse effects of antiarrhythmic agents. Results from recent trial have altered the general approach to management of ventricular arrhythmias. The results of the Cardiac Arrhythmia Suppression Trials (CAST I and II) exemplified the disappointing results from numerous other studies, revealing the overall lack of efficacy of class I agents in reducing mortality in patients with coronary artery disease and asymptomatic premature ventricular complexes (PVCs). The results of CAST I and II also demonstrated the higher likelihood of older patients developing ventricular arrhythmias and toxicity to antiarrhythmic agents. Combined results of these studies have discouraged empirical antiarrhythmic therapy, especially in older patients with asymptomatic PVCs. In contrast, secondary prevention trials with beta-blockers in post-myocardial infarction patients have shown definitive survival benefit and reduction in ventricular arrhythmias, especially in the older patient population. Smaller trials with amiodarone have also shown survival benefit in post-myocardial infarction patients with or without PVCs. Management of ventricular tachycardia and fibrillation has become less empirical and more systematic with use of electrophysiologically guided and/or Holter monitor-guided therapy. Sotalol and amiodarone are especially effective agents. The efficacy of implantable cardioverter/defibrillators are also being compared with medical therapy systematically in multicentre trials. In general, empirical antiarrhythmic therapy is discouraged especially in the treatment of asymptomatic PVCs and should be reserved for systematic use in life-threatening arrhythmias.

Characterization of a new cholecystokinin receptor antagonist FK480 in in vitro isolated rat pancreatic acini

Biochemical and pharmacologic characteristics of a newly developed benzodiazepine derivative (S)-N-[1-(2-fluorophenyl)-3,4, 6,7-tetrahydro-4-oxo-pyrrolo-[3,2,1-jk] [1,4]benzodiazepine-3-yl]-1H-indole-2-carboxamide (FK480) as a cholecystokinin (CCK) receptor antagonist were examined in the isolated rat pancreatic acini and compared with those of MK-329 and loxiglumide. FK480, MK-329, and loxiglumide inhibited CCK octapeptide (CCK-8)-stimulated amylase release and binding of [125I]CCK-8 in a concentration-dependent manner, with a half-maximal inhibition (ID50) at 1.30 +/- 0.12 nM, 1.33 +/- 0.21 nM, and 1.27 +/- 0.23 microM, respectively, for amylase release, and 0.40 +/- 0.06 nM, 0.68 +/- 0.08 nM, and 0.38 +/- 0.03 microM, respectively, for [125I]CCK-8 binding. The antagonism was competitive in nature because these three compounds caused a parallel rightward shift of the dose-response curve for CCK-8-stimulated amylase secretion, without altering the maximal increase. The antagonism produced by FK480 was specific for CCK in that the effects of other receptor secretagogues or agents bypassing receptors were not altered. FK480 not only prevented but also reversed CCK-8-stimulated amylase release. This compound caused a residual inhibition of the action of CCK-8. When acini were preincubated with 100 nM FK480 for 30 min, the subsequent dose-response curve to CCK-8 was shifted 10-fold toward higher concentration. Similar results were obtained with MK-329 but not with loxiglumide. FK480 appeared to be bound to the receptors on acinar cells in a slowly dissociating state.(ABSTRACT TRUNCATED AT 250 WORDS)

The management and long-term results of Japanese pediatric liver transplant recipients

We investigated the long-term results and ongoing management issues of 39 Japanese children who underwent liver transplantation in Brisbane, Australia. Whole liver grafts were used in 15 patients (Wh group) and reduced-size grafts were used in 24 patients (Re group). The 1-year and 3-year survival rates were 74% and 60%, respectively, and all cases of late mortality which occurred after 6 months were due to infection. Statistical analysis showed no differences between the Wh and Re groups with regard to late mortality or liver function tests, although 4 of 24 (16.7%) patients from the Re group developed a recurrence of esophageal varices. Three patients treated with cyclosporine developed lymphoproliferative disorders following transplantation, but none of the patients developed severe nephrotoxicity or hypertension. Although a "catch-up" gain in weight was observed, poor growth in height was displayed, and there were no differences between the Wh and Re groups in this regard. Thus, we conclude that late complications of liver transplantation in children are common and further studies are necessary to evaluate the ongoing growth problems.

Use of near infrared reflectance spectroscopy in the screening for biliary atresia

Early diagnosis is crucial for treatment and prognosis of biliary atresia (BA). We used near infrared reflectance spectroscopy (NIRS) for screening of BA. Fecal samples were collected from 200 healthy infants and 16 infants for whom either BA or neonatal hepatitis was diagnosed. Diagnoses were made retrospectively by other diagnostic methods, including laparotomy. The samples (0.5 g each) were manually homogenized. Reflected light from the surface of feces was measured by NIRS. Absorbance peak spectra for fecal fat and conjugated bilirubin were determined before the study, and proved to be 730, 1158, and 1210 nm, respectively. Two cutoff points were set in the second-derivative spectrum: the first (> -0.005) at 730 nm for conjugated bilirubin, and the second (< 1.0) at 1,158:1,210 nm for fat (to include all patients with BA). The sensitivity of NIRS in the diagnosis of BA was 100%, and the specificity was 95.2%. The authors conclude that NIRS is a simple, rapid, noninvasive, and precise technique for the early diagnosis of BA.