Intraductal papillary mucinous tumors of the pancreas comprise 2 clinical subtypes: differences in clinical characteristics and surgical management

HYPOTHESIS

Intraductal papillary mucinous tumors (IPMTs) of the pancreas may be meaningfully construed as representing 2 clinically distinct subtypes: main duct tumors (MDT) and branch duct tumors (BDT).

DESIGN

Retrospective study.

SETTING

University hospital from January 1988 through December 1994.

PATIENTS AND INTERVENTION

We reviewed diagnostic findings and late results of surgical treatment in 30 patients with IPMT.

RESULTS

The tumor was located in the head of the pancreas more often in BDT than in MDT (65% [11/17] and 23% [3/13], respectively). Of the 13 patients with MDTs, 12 (92%) had intraductal papillary adenocarcinoma (noninvasive and minimally invasive types) and/or carcinoma in situ (carcinoma in situ: low papillary and/or flat tumor cells), and 3 (23%) had stromal invasion. Of the 17 patients with BDTs, 5 (29%) had intraductal papillary adenocarcinoma and/or carcinoma in situ. Two pancreatoduodenectomies and 8 pylorus-preserving pancreatoduodenectomies were performed in 10 of the 17 patients with BDTs, distal pancreatectomy in 7 patients with MDTs, and total pancreatectomy in 4 patients with MDTs. The 5-year survival rates were 47% for MDT and 90% for BDT. Four of 6 patients with MDTs who died had local recurrence. One patient died of liver metastasis and 1 of esophageal cancer. Only 1 patient with BDT of the 2 who died had recurrent disease.

CONCLUSIONS

Intraductal papillary mucinous tumors may be composed of 2 clinically distinct subtypes: MDTs and BDTs. Initially, although distal pancreatectomy can be recommended for most MDTs, the need for cancer-free margins in this more aggressive type may necessitate total pancreatectomy. Pylorus-perserving pancreatoduodenectomies is recommended for most BDTs, but, because these tumors are more often adenomas, a good prognosis can be expected.

Moscatilin from Dendrobium nobile, a naturally occurring bibenzyl compound with potential antimutagenic activity

A bibenzyl compound that possesses antimutagenic activity was isolated from the storage stem of Dendrobium nobile. The isolated compound suppressed the expression of the umu gene following the induction of SOS response in Salmonella typhimurium TA1535/pSK1002 that have been treated with various mutagens. The suppressive compound was mainly localized in the n-hexane extract fraction of the processed D. nobile. This n-hexane fraction was further fractionated by silica gel column chromatography, which resulted in the purification and subsequent identification of the suppressive compound. EI-MS and (1)H and (13)C NMR spectroscopy were then used to delineate the structure of the compound that confers the observed antimutagenic activity. Comparison of the obtained spectrum with that found in the literature indicated that moscatilin is the secondary suppressive compound. When using 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) as the mutagen, moscatilin suppressed 85% of the umu gene expression compared to the controls at <0.73 micromol/mL, with an ID(50) value of 0.41 micromol/mL. Additionally, moscatilin was tested for its ability to suppress the mutagenic activity of other well-known mutagens such as 4-nitroquinoline-1-oxide (4NQO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), UV irradiation, 3-amino-1,4-dimethyl-5H-pyrido[4,3b]indole (Trp-P-1), benzo[a]pyrene (B[a]P), and aflatoxin B(1) (AFB(1)). With all of the aforementioned chemicals or treatments, moscatilin showed a dramatic reduction in their mutagenic potential. Interestingly, moscatilin almost completely suppressed (97%) the AFB(1)-induced SOS response at concentrations <0.73 micromol/mL, with an ID(50) of 0.08 micromol/mL. Finally, the antimutagenic activities of moscatilin against furylfuramide and Trp-P-1 were assayed by the Ames test using the S. typhimurium TA100 strain. The results those experiments indicated that moscatilin demonstrated a dramatic suppression of the mutagenicity of only Trp-P-1 but not furylfuramide.

Adjuvant immunotherapy using fibroblasts genetically engineered to secrete interleukin 12 prevents recurrence after surgical resection of established tumors in a murine adenocarcinoma model

BACKGROUND

To explore effective therapeutic strategy against cancer of the gastrointestinal tract, tumor vaccination using fibroblasts secreting interleukin-12 (IL-12) was developed as an adjuvant therapy against murine tumor after surgical resection.

METHODS

Initially, IL-12 was genetically engineered into fibroblasts (IL-12/3T3 cells), and then we evaluated in vivo and in vitro antitumor effects. In the vaccination model, irradiated C-26 tumor mass was reinoculated intradermally with IL-12/3T3 cells in mice as a tumor vaccine to examine how much it suppresses tumor recurrence.

RESULTS

IL-12/3T3 cells producing 7.2 ng/10(6) cells/24 h murine IL-12 in vitro exerted dose-dependent potent tumor suppression when coinoculated with C-26 cells in vivo. Specific immunity was also acquired in 63% of mice in vivo. In the vaccination model, protective immunity was developed in 70% of mice that were inoculated with irradiated tumor mass and IL-12/3T3 cells. In addition, local recurrence was not observed in vaccinated mice, although 44% of control mice had recurrence.

CONCLUSIONS

Coinoculation of genetically engineered fibroblasts secreting IL-12 with irradiated tumor mass was proved to be an effective tumor vaccine. This system of vaccination is easily applicable to clinical situations, particularly to human gastrointestinal tract cancers.

[Therapeutic strategy for the recurrence of pancreatic cancer following pancreatectomy]

It is well-known that the patients with pancreatic cancer are vulnerable for recurrence such as local relapse and liver metastasis after surgical resection. We revealed that a patient with local relapse without liver metastasis showed better prognosis as compared with a patient having liver metastasis. We usually adapt further therapeutic intervention for local recurrence using external radiation therapy accompanied with 5FU infusion as a radiosensitizer, if the patient is not revealed with liver metastasis. On the other hand, there is no effective intervention for liver metastasis accompanying pancreatic cancer, as small lesions of multiple liver metastases progress rapidly. We insert the tip of catheter in proper hepatic artery in order to infuse MMC once a week at outpatient clinic. However, we were not yet able to evaluate the effect of arterial infusion therapy.

Prolonged release of drug from O/w emulsion and residence in rat nasal cavity

The present study evaluated the usefulness of an o/w emulsion for slowing the release of chlorpheniramine maleate (CM) and prolonging drug residence in the nasal cavity. O/w emulsion formulations of medium chain triglycerides (MCT) were prepared, and their physicochemical properties and drug release kinetics were evaluated using the in vitro dialysis tube method. Drug disappearance from the rat nasal cavity was determined in in situ nasal experiments. CM partitioned in oil droplets by pH, as predicted by pH partition theory. With higher MCT concentration and pH, slower release of CM was observed. CM disappearance (kapp) from the rat nasal cavity was influenced by the amount of drug partitioned in the oil droplets with both the perfusion and deposit methods, and the kapp of CM decreased with increase in MCT concentration and pH. Moreover, with the deposit method, CM remaining in the nasal cavity exhibited a biphasic profile of disappearance, which complied with a saturated process. Because a very small portion of MCT might be adsorbed and formed a pseudooily layer on the mucous membranes, prolongation of CM residence on the mucous membrane was attained. These findings suggest that emulsion containing 30% MCT at pH 8 may be useful for inclusion in controlled-release formulations of CM for intranasal drug delivery in the treatment of allergy.

Evaluation of drug disappearance from nasal cavity by the deposit method

In order to evaluate antiallergic intranasal formulations, the rates of drug disappearance from rat nasal cavity were estimated by the deposit and perfusion methods. The deposit method, which estimates changes in the amount of residual drug in the nasal cavity following washout of the deposited drug over time after application, yielded a good correlation between apparent disappearance rate constant and the combination of lipophilicity and molecular weight. Since the deposit method can be used only with delivery of small amounts of drug to the nasal cavity, the physiological characteristics of the nasal membrane readily affect drug disposition in tests performed with it, and adsorptive drugs such as parabens exhibited rapid disappearance. Doses used clinically for intranasal administration are usually small, and in the case of antiallergic formulations, it is important to maintain the drug concentration in the nasal mucous membrane. The deposit method should be useful for evaluating intranasal antiallergic drug formulations.

Suppression of the SOS-inducing activity of Trp-P-1 and aflatoxin B1 by meso-dihydroguaiaretic acid from Machilus thunbergii in the Salmonella typhimurium TA1535/pSK1002 umu test

The methanol extract from Machilus thunbergii showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which requires liver metabolizing enzymes. The methanol extract from M. thunbergii was successively re-extracted with chloroform, butanol and water. A suppressive compound in the chloroform extract fraction was isolated by SiO2 column chromatography and identified as meso-dihydroguaiaretic acid by GC-MS, and 1H- and 13C-NMR spectroscopy. Meso-dihydroguaiaretic acid inhibited of the SOS-inducing activity of Trp-P-1 in the umu test. Gene expression was suppressed by 62% at less than 0.18 mumol/ml, the ID50 value being 0.08 mumol/ml. Compound 1 was also assayed with aflatoxin B1 (AfB1) and showed a suppressive effect.

Mutational specificity of the ferrous ion in a supF gene of endonuclease III/VIII deficient Escherichia coli

When 125 microM Fe2+/EDTA treated plasmid pUB3 was used to transfect an Escherichia coli NKJ2004 (nth nei) host, which is totally defective in glycosylases for thymine glycol and 5-hydroxycytosine, a 3.7 fold increase in mutation frequency was observed. Among 46 supF mutants sequenced, 28 had base substitutions, with G:C-->C:G transversion predominant (14 cases), followed by G:C-->T:A transversion (6 cases) and G:C-->A:T transition (6 cases). The results are consistent with our previous Fe2+ mutagenesis results where, in the wild type host, 78% were base substitutions, with G:C-->C:G transversion (59%) predominant, followed by G:C-->T:A transversion (28%) and G:C-->A:T transition (11%). Treatment of pUB3 DNA with Fe2+/EDTA did not yield formation of Endonuclease III sensitive sites. The possibility of 5-hydroxycytosine as the causative lesion for Fe2+ induced G:C-->C:G transversion is discussed.

Biliary excretion of glycyrrhizin in rats: kinetic basis for multiplicity in bile canalicular transport of organic anions

PURPOSE

To examine the presence of multiplicity for the biliary excretion of xenobiotic conjugates, we studied the disposition of glycyrrhizin (GR), which has glucuronide within its molecular structure and has the ability to inhibit the biliary excretion of liquiritigenin (LG) glucuronides.

METHODS

GR was administered intravenously as a bolus to Sprague-Dawley (SD) rats which received an i.v. infusion of inhibitors (dibromosulfophthalein (DBSP) and indocyanine green (ICG)) at their transport maximum rates. Biliary excretion of GR was also examined in Eisai hyperbilirubinemic rats (EHBR), which have a hereditary defect in the canalicular transport system of several organic anions.

RESULTS

Infusion of ICG did not affect the biliary excretion of GR, whereas infusion of DBSP reduced it significantly. The plasma concentration of GR was increased by DBSP but not by ICG. In EHBR, the biliary excretion of GR was severely impaired, resulting in an increase in the plasma concentration of GR.

CONCLUSIONS

These findings suggest (1) that the biliary excretion of GR is mediated by the system which is shared by DBSP and LG glucuronides but not by ICG and (2) that this system is hereditarily defective in EHBR. Together with our previous findings, the multiplicity for the biliary excretion of organic anions is shown.

Central conduction in somatosensory evoked potentials: comparison of ulnar and median data and evaluation of onset versus peak methods

To compare central conduction in ulnar and median nerve somatosensory evoked potentials (SEPs), we recorded SEPs from the neck and scalp elicited by median and ulnar nerve stimulation in 46 normal young adults. We determined the central conduction time (CCT) in each subject from peak-to-peak and onset-to-onset measurements. The mean value of the onset CCT for the ulnar nerve SEP was 6.2 +/- 0.3 msec, and for the median nerve SEP, 5.9 +/- 0.3 msec. Onset CCT was significantly longer for the ulnar nerve SEP, and there was a significant correlation between onset CCT in both median and ulnar nerve SEPs and subject height. In contrast, the mean value of the "conventional" peak CCT for the ulnar nerve SEP was 5.6 +/- 0.6 msec, and for the median nerve SEP, 5.8 +/- 0.5 msec, with no significant difference between them. In addition, the peak CCT was not correlated with subject height in the ulnar or median nerve SEPs. Our findings suggest that onset CCT measurement is superior to the conventional peak CCT measurement for ulnar as well as median nerve SEPs, and confirm that the central conduction pathway for the ulnar nerve SEP is slightly longer than that for the median nerve SEP.

Establishment of an experimental liver metastasis model by intraportal injection of a newly derived human pancreatic cancer cell line (KLM-1)

CONCLUSION

It is suggested that this liver metastasis model formed by a highly metastatic variant (KLM-1) is valuable for the study of the liver metastatic processes of human pancreatic cancer.

BACKGROUND

Liver metastasis in the early postoperative period is one of the causes for the poor prognosis of patients with resected pancreatic cancer. Therefore, it is necessary to establish an experimental model to study the mechanisms of liver metastasis in pancreatic cancer.

METHODS

Human pancreatic cancer cell lines (PK-1, PK-9, and KLM-1) were injected into the portal vein of nude mice with or without pretreatment with antiasialo GM1, and colonies of liver metastases were counted for comparison of metastatic ability of these cell lines. Biological and histopathological characteristics of the highly liver metastatic cell line (KLM-1) were compared with its parent cell line (PK-1).

RESULTS

PK-1 cells and PK-9 cells rarely formed liver metastasis foci, but pretreatment with antiasialo GM1 promoted liver metastasis. KLM-1 cells formed liver metastases at the rate of 70% even without antiasialo GM1 pretreatment. KLM-1 cells had such biological characteristics as short doubling time, short lag phase, and resistance to NK cytotoxicity. After intraportal injection of 125I-labeled KLM-1 cells, radioactivity as well as micrometastases were detected in the liver at 72 h.

Pharmacokinetics and polymorphic oxidation of dextromethorphan in a Japanese population

The plasma concentration and cumulative urinary excretion over 34 h of dextromethorphan, free and conjugated dextrorphan, and 3-hydroxymorphinan were determined in seven healthy Japanese subjects after oral administration of 30 mg dextromethorphan hydrobromide. Conjugated metabolites were extensively present, whereas no detectable dextromethorphan or free metabolites were observed in the plasma of any subject. On average, 72% of the dose was excreted in urine within 34 h. This was detected mainly as conjugated metabolites with only slight traces of dextromethorphan and free metabolites. From the time-courses of the metabolic ratio (the ratio of urinary output of dextromethorphan to dextrorphan), the metabolic ratios seemed to become constant 7.5 h after oral administration. Phenotyping was performed using metabolic ratios in 75 unrelated healthy Japanese subjects (43 males and 32 females). The logarithmic metabolic ratio was bimodally distributed and one subject (1.3%) was identified as a poor metabolizer.

Serum levels of circulating intercellular adhesion molecule 1 in hepatocellular carcinoma

BACKGROUND/AIMS

This is a comparative study of the relationship between.

MATERIAL AND METHODS

Serum levels of circulating intercellular adhesion molecule-1 (cICAM-1) were measured by ELISA assay in four patients with chronic hepatitis (CH), 16 with liver cirrhosis (LC), 38 with hepatocellular carcinoma (HCC), and in nine healthy controls.

RESULTS

No significant difference in cICAM-1 levels was observed between LC and HCC. The cICAM-1 level in HCC did not correlate with tumor markers but correlated well with tumor size. cICAM-1 level in HCC Stage III + IV was significantly higher than that of Stage I, and was higher in HCC with liver metastasis as opposed to HCC without metastasis. Furthermore, the cICAM-1 level of HCC decreased significantly after hepatectomy.

CONCLUSION

These findings showed a close relationship between cICAM-1 and the progress of intrahepatic metastasis of HCC, indicating a possibility for using cICAM-1 as a prognostic marker.

Studies on antiulcer agents. IV. Antiulcer effects of 2-benzylthio5,6,7,8-tetrahydro-4(3H)-quinazolinones and related compounds

With a view to finding more effective antiulcer agents, a series of 2-benzylthio-5,6,7,8-tetrahydro-4(3H)-quinazolinones and related compounds were synthesized and evaluated in a histamine-stimulated gastric secretion model. The sodium salt of the 2-(dimethylamino)benzylthio derivative (8) showed gastric mucosal protection and gastric antisecretion activities, and was also effective against experimental gastric and duodenal ulcers induced by some ulcerogenic agents. Based on a comparison of the antiulcer properties of 8 with those of the lead compounds (1 and 2) and cimetidine, it appears that, for improvement of antiulcer activity, the reduction of gastric acidity is a more important factor than the reduction of gastric volume output or gastric total acid output.

Studies on antiulcer agents. II. Antiulcer properties of N-(1H-tetrazol-5-yl)-2-anilino-5-pyrimidinecarboxamides inhibiting release of histamine from passively sensitized rat peritoneal mast cells

With the aim of applying mast cell-stabilizing agents as antiulcer agents, N-(1H-tetrazol-5-yl)-2-anilino-5-pyrimidinecarboxamides were synthesized, and initially evaluated pharmacologically for activity in the rat passive cutaneous anaphylaxis test by oral administration. The most active compound 6 was proved to inhibit potently the release of histamine from passively sensitized rat peritoneal mast cells in vitro. When compared with other mast cell-stabilizing agents and an antiulcer agent, compound 6 was found to show excellent gastric mucosal protection and gastric antisecretion activities. Furthermore, compound 6 revealed good activity against acidified aspirin ulcer in rats and water-immersion stress ulcer in rats.

Studies on antiulcer agents. I. Synthesis and pharmacological properties of ethyl 2-[(1H-benzimidazol-2-yl)sulfinylmethyl]-4-dimethylamino-5- pyrimidinecarboxylate, a new H+/K(+)-ATPase inhibitor possessing mucosal protective activity

Ethyl 2-[1H-benzimidazol-2-yl)sulfinylmethyl]-4-dimethylamino-5- pyrimidinecarboxylate (2) has been synthesized and evaluated for antiulcer properties. Compound 2 is a H+/K(+)-ATPase inhibitor that affords mucosal protection against absolute ethanol-induced gastric lesions in rats after oral and parenteral administrations. On the other hand, omeprazole, a representative H+/K(+)-ATPase inhibitor, showed mucosal protective action only after oral administration, indicating that it required gastric acid secretion to generate activity. The antiulcer activity of 2 in animal models, such as water-immersion stress-induced gastric ulcer in rats and acidified aspirin-induced gastric ulcer in rats, was three times higher than that of cimetidine.

Multiple systems for the biliary excretion of organic anions in rats: liquiritigenin conjugates as model compounds

Liquiritigenin (LG), 2, 3-dihydro-7-hydroxy-2-(4-hydroxyphenyl)-(S)-4H-1-benzopyran-4-1, is metabolized to five kinds of conjugates (glucuronides and sulfates) that are excreted predominantly into the bile (Shimamura et al., 1993). Using LG as a model compound, we studied the multiplicity for the biliary excretion of conjugates in vivo. LG was administered i.v. as a bolus to Sprague-Dawley rats (SD rats) that received i.v. infusions of the inhibitors [glycyrrhizin (GR), dibromosulfophthalein (DBSP) and indocyanine green (ICG)] at their maximal transport rates. The infusion of GR and that of DBSP reduced significantly the biliary excretion of all the conjugates except LG 4',7-O-disulfate (M3), whereas infusion of ICG did not affect the excretion of conjugates. To minimize the effect of the other tissues on the disposition of the conjugates, the apparent biliary excretion clearance (CLbile,app) was calculated. The CLbile,app values of LG 4'-O-glucuronide (M1), LG 7-O-glucuronide (M2), LG 4'-O-glucuronide 7-O-sulfate (M4) and LG 7-O-glucuronide 4'-O-sulfate (M5) were significantly reduced by GR and DBSP infusion, whereas the CLbile, app value of M3 was not affected by these inhibitors. The CLbile, app values of all the conjugates except M2 were not reduced by ICG infusion. In Eisai hyperbilirubinemic rats, which have a hereditary defect in the canalicular transport system for several organic anions, the biliary excretion clearance of M1, M2, M4 and M5 was markedly reduced, whereas that of M3 was comparable with that in control rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Variability in absorption lag time of pyridoxal phosphate under fasting and pre- and post-meal conditions

Inter-individual variations in the absorption lag time of pyridoxal phosphate were determined after administration of an enteric-coated tablet (EC) or a plain capsule (PC) to 113 healthy volunteers under fasting, pre-meal, and post-meal conditions. The absorption lag time of pyridoxal phosphate was assessed from the urinary excretion of 4-pyridoxic acid after administration of EC and PC. Significantly larger lag times after administration of both formulations were observed under post-meal conditions than under pre-meal conditions (0.477 +/- 0.315 h versus 0.081 +/- 0.086 h for PC and 1.995 +/- 1.345 h versus 1.064 +/- 1.327 h for EC), indicating that the mean gastric emptying rates of both a solution and a tablet were delayed after food intake. The lag time for PC showed little inter-individual variation with (0-1.2 h) or without food (0-0.25 h), whereas that for EC showed markedly large inter-individual variation, from 0.25 to 2.63 h (median, 1.5 h) in the fasting condition, from 0.25 to > 5.5 h (median 0.25 h) under pre-meal conditions, and from 0.25 to > 5.5 h (median 1.25 h) under post-meal conditions. The effect of food on the gastric emptying rate of a solution appears to be almost uniform, whereas that for a tablet is so unpredictable that a reliable absorption rate for an enteric-coated tablet cannot be expected, particularly under pre- and post-meal conditions.

Identification of tissues responsible for the conjugative metabolism of liquiritigenin in rats: an analysis based on metabolite kinetics

We kinetically examined tissues responsible for the conjugative metabolism (glucuronidation and sulfation) of a component in a crude drug, liquiritigenin (LG; 2,3-dihydro-7-hydroxy-2-(4- hydroxyphenyl)-(S)-4H-1-benzopyran-4-one) in rats in vivo. LG has been found to form five kinds of conjugates (4'-O-glucuronide (M1), 7-O-glucuronide (M2), 4',7-O-disulfate (M3), 4'-O-glucuronide-7-O-sulfate (M4) and 7-O-glucuronide-4'-O-sulfate (M5)). Analysis based on metabolite kinetics [K. S. Pang, J. Pharmacokin. Biopharm., 13, 633 (1985)] of the area under the plasma concentration curves (AUCplasma) and cumulative biliary excretions (Aibile) of the ligands after intravenous or hepatic portal venous administration of LG revealed that the liver has the ability to generate all the metabolites. For M1 and M2, the apparent biliary excretion clearance (CLbile,app) obtained by dividing the biliary excretion rate for the metabolite by the plasma concentration of the metabolite decreased with time, confirming that M1 and M2 were formed in the liver. To further analyze the formation rate constants for metabolites in each tissue, we measured the ligand content in several tissues after intravenous administration of LG. By correcting the content of metabolites that were taken up from the plasma, we found that the formation rates per gram of tissue were largest in the liver, except for M3. The metabolic capability of the kidney for M1 and M2 was 15% and 60%, respectively, to that of the liver whereas for M3, the metabolic ability of the kidney was 2.5-fold greater than that of the liver.(ABSTRACT TRUNCATED AT 250 WORDS)

[Rapid recovery of chronic inflammatory demyelinating polyneuropathy induced by steroid pulse therapy--changes in nerve conduction]

A 47-year-old female patient with chronic inflammatory demyelinating polyneuropathy started to recover from her numbness and weakness within a few hours following the commencement of intravenous methylprednisolone 1,000 mg. In parallel with the recovery of muscle strength, a prolonged latency time of the M-wave was normalized within a day by a revival of the new motor units with a normal latency. In many cases with CIDP, it has been recognized that the gradual decrease in latency time over weeks is a later phenomenon following early increase in amplitude of the M-wave during recovery of weakness, which is explained by remyelinating process. On the other hand, the revival of motor units with a normal latency time from demyelinating conduction block is difficult to explain by remyelinating process, because remyelinating fibers usually have a very slow conduction velocity. Some minor morphological changes of paranodes or humoral factors may be partly responsible for development conduction block in CIDP.