New liposome-radionuclide-chelate combination for tumor targeting and rapid healthy tissue clearance

Radionuclide imaging and therapy are promising methods for controlling systemic cancers; however, their clinical application has been limited by excessive radionuclide accumulation in healthy tissues. To minimize radionuclide accumulation in non-cancerous tissues while ensuring sufficient build up in tumors, we aimed to develop a method that controlled the in vivo dynamics of radionuclides post-administration. To this end, we describe a novel strategy that combines liposomes, a potent carrier system for drug delivery, with unique radionuclide-ligand complexes based on 111In-ethylenedicysteine. Conventional 111In-ligand-complexes-carrying liposomes delivered substantial amounts of radionuclides to tumors; however, they also accumulated in the liver and spleen. In contrast, 111In-ethylenedicysteine-carrying liposomes greatly reduced non-specific accumulation, while being retained selectively at high doses within tumors. Liposomes were rapidly broken down in the liver, releasing encapsulated 111In-ligand complexes. Among the chelates used, only 111In-ethylenedicysteine could escape from the liver and be excreted in the urine. Instead, most liposomes remained intact in tumors, retaining the radionuclide-ligand complexes within them. Therefore, high tumor accumulation was obtained regardless of the type of 111In-ligand complexes in the liposomes. In vivo single photon emission computed tomography/computed tomography imaging with 111In-ethylenedicysteine-carrying liposomes accurately revealed tumor-selective radionuclide retention with little background. Hence, our new strategy could greatly enhance tumor-to-healthy tissue ratios, improve diagnostic imaging, boost therapeutic efficacy, reduce toxicity to healthy tissues, and facilitate radionuclide imaging and therapy.

Preclinical Pharmacokinetic and Safety Studies of Copper-Diacetyl-Bis(N4-Methylthiosemicarbazone) (Cu-ATSM): Translational Studies for Internal Radiotherapy

Hypoxia plays important roles in the prognosis of malignant brain tumors such as glioblastoma because it causes drug delivery deficiencies and the induction of hypoxia-inducible factor-1α in tumor cells. Extensive hypoxic areas are associated with poor prognosis of these fatal diseases. We previously reported that multiple administrations of the hypoxia-targeted internal radiotherapy agent ⁶⁴Cu-diacetyl-bis(N⁴-methylthiosemicarbazone) (⁶⁴Cu-ATSM), four times at intervals of 1 or 2 weeks, show antitumor effects in glioblastoma without treatment-related adverse events. Before initiating clinical trials, preclinical safety studies using Cu-ATSM composed of stable isotopes and its precursor ATSM were required to understand the potential risks of systemic and repeated chemical exposure of our investigational drug. In this study, the concentrations of Cu-ATSM and ATSM in mouse plasma after intravenous administration were determined by liquid chromatography–tandem mass spectrometry, and the half-lives were estimated to be 21.5 and 22.4 minutes for Cu-ATSM and ATSM, respectively. Based on this result, approach 2 of the current ICH M3 [R2] guideline was adopted, and a 7-day intravenous toxicity study was conducted in mice. Cu-ATSM and ATSM in a ratio of 2:25 mimicking our current investigational drug was used, and no adverse effects were observed when Cu-ATSM and ATSM were administered at 81 μg/kg. These results and those of previous studies suggest that our current investigational drug formulation containing Cu-ATSM and ATSM at a dose of 15 μg can be safely administered to patients once per week for 4 weeks for treatment with ⁶⁴Cu-ATSM.

Identification of mesenchymal stem cell (MSC)-transcription factors by microarray and knockdown analyses, and signature molecule-marked MSC in bone marrow by immunohistochemistry

Although ex vivo expanded mesenchymal stem cells (MSC) have been used in numerous studies, the molecular signature and in vivo distribution status of MSC remain unknown. To address this matter, we identified numerous human MSC-characteristic genes--including nine transcription factor genes--using DNA microarray and real-time RT-PCR analyses: Most of the MSC-characteristic genes were down-regulated 24 h after incubation with osteogenesis-, chondrogenesis- or adipogenesis-induction medium, or 48-72 h after knockdown of the nine transcription factors. Furthermore, knockdowns of ETV1, ETV5, FOXP1, GATA6, HMGA2, SIM2 or SOX11 suppressed the self-renewal capacity of MSC, whereas those of FOXP1, SOX11, ETV1, SIM2 or PRDM16 reduced the osteogenic- and/or adipogenic potential. In addition, immunohistochemistry using antibodies for the MSC characteristic molecules--including GATA6, TRPC4, FLG and TGM2--revealed that MSC-like cells were present near the endosteum and in the interior of bone marrow of adult mice. These findings indicate that MSC synthesize a set of MSC markers in vitro and in vivo, and that MSC-characteristic transcription factors are involved in MSC stemness regulation.

Short Communication: A Positive Relationship Between the First Ovulation Postpartum and the Increasing Ratio of Milk Yield in the First Part of Lactation in Dairy Cows

The aim of the present study was to examine the relationship between characteristics of the lactation curve, on the basis of daily milk yield, and ovulation within 3 wk postpartum as an indicator of early return to luteal activity in dairy cows. Lactation records from 46 lactating Holstein cows between calving and 305 d postpartum were studied. Milk samples were collected twice weekly between d 7 and 100 for later determination of progesterone concentrations. Occurrence of an early first ovulation was determined by an increase in milk progesterone by 3 wk after calving. Milk yield was recorded daily until 305 d postpartum, and average yield was calculated weekly. The lactation curve was characterized by 8 indices on the basis of the weekly average of milk yield as follows: a) first-week milk yield; b) peak milk yield; c) actual 305-d milk yield; d) peak week; e) difference in milk yield between the first week and peak week; f) difference in milk yield between the peak week and last week (43rd week postpartum); g) ratio of increase in milk yield between wk 1 and the week of peak yield; and h) ratio of decline in milk yield between the week of peak yield and the last week. Indices g and h were calculated as linear. The number of cows having ovulated by 3 wk postpartum was 22 (47.8%). The resumption of ovarian cycles with normal luteal phases occurred earlier in ovular cows than in anovular cows (32.0 d vs. 57.1 d). Although total milk yield did not differ between ovular and anovular cows, the ratio of increase in milk yield from the first week to the peak week (index g) in ovular cows was smaller compared with that of anovular cows (1.71 vs. 2.54). In addition, the ratio of increase in milk yield from the first week to the third week postpartum was greater in anovular cows by 3 wk postpartum (ovular = 1.43 +/- 0.23 vs. anovular = 2.32 +/- 0.29). In conclusion, the present study demonstrates that a greater increasing ratio of milk yield during early lactation may delay resumption of ovarian cycles after parturition. Therefore, this study is the first to demonstrate statistically that a smaller increasing ratio of milk yield (index g) during early lactation may have a beneficial effect on the first ovulation by 3 wk postpartum.

Site-specific effect of estradiol on gene expression in the adipose tissue of ob/ob mice

Sex hormones are likely to be involved in sex differences in adipose tissue distribution. To test whether estrogen regulates genes expressed in the adipose tissue in a site-specific manner, we studied the effect of exogenous estradiol on the gene expression in visceral and subcutaneous adipose tissues of male ob/ob mice. We screened genes expressed in a site- and sex-specific manner, and genes that were affected by exogenous estradiol by DNA chip analysis. They were verified by real-time PCR. Myosin heavy chain 2B (Myh4) and phosphoglycerate mutase muscle-specific subunit (Pgam) were expressed specifically in the subcutaneous adipose tissue, and uroplakin IIIb (UP3) was expressed specifically in the visceral adipose tissue. DEAD-box Y RNA helicase (DBY) and eukaryotic initiation factor 2 gamma Y (eIF2gamma Y) were expressed only in male adipose tissue. X-chromosome inactive specific transcript (Xist) was expressed only in female adipose tissue. When estradiol was subcutaneously administrated to male mice, the expression of monocyte-chemoattractant protein-1 (MCP-1) and androgen receptor (AR) genes was regulated in a site-specific manner. The difference in the amount of estrogen receptor did not account for the site-specific effect of estrogen. Our findings show that estrogen affects the expression of some adipocyte genes in a site-specific manner.

Insulin-like growth factor-I (IGF-I) system during follicle development in the bovine ovary: relationship among IGF-I, type 1 IGF receptor (IGFR-1) and pregnancy-associated plasma protein-A (PAPP-A)

Insulin-like growth factor-I (IGF-I) system that is exerted mainly through the type 1 IGF receptor (IGFR-1) and releasing of free IGF-I is regulated by the proteases of IGF-binding proteins (IGFBPs), an important factor in follicle development of bovine ovary. The aims of the present study were to examine the mRNA expressions of IGF-I, IGFR-1 and pregnancy-associated plasma protein-A (PAPP-A) in granulosa cells and theca tissues during bovine follicular development and the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of these genes in cultured bovine granulosa cells. Follicles were classified into four groups such as small follicle (SF), estrogen inactive dominant follicle (EID), estrogen active dominant follicle (EAD) and preovulatory follicle (POF). The concentration of free IGF-I in follicular fluid of POF was significantly higher than those in EID, whereas the total IGF-I in follicular fluid did not change at all developmental stages. The expression of IGF-I mRNA was not detected in the granulosa cells at all at any developmental stages but the expression was detected in the theca tissues. The amount of IGFR-1 mRNA in granulosa cell showed the constant level at all developmental stages except EID. The expressions of IGFR-1 and PAPP-A in cultured bovine granulosa cells were stimulated with FSH but not with E2. The PAPP-A mRNA expression was stimulated by FSH in presence of 1 ng/ml E2. These results indicate that IGF-I in follicular fluid is mainly derived from the circulation and that FSH is an inducer for the expression of IGFR-1 and PAPP-A genes in granulosa cells. Therefore, we suggest that PAPP-A stimulated with FSH play a crucial role for IGF-I system in bovine follicular development.

42 PREPARTUM HORMONAL CHANGES IN RECIPIENT COWS FOR SOMATIC CELL CLONED FETUSES

Placental estrogens are associated with fetal growth and development, and play important roles in the initiation of the parturition process. In the delivery of somatic cell-cloned (SC) calves, recipient cows show a weak and unclear symptom of parturition, although large offspring syndrome (LOS) frequently occurs. The mortality of calves by dystocia decreases the efficiency of SC cattle production. In this study, we examined peripheral estrone (E1), estradiol-17� (E2), estrone sulfate (E1S), and progesterone (P4) levels during preparturition in recipients of SC and in vivo calves. Recipients were administered 20 mg dexamethasone (DEX) at Days 276-288 of pregnancy, followed by 0.75-1 mg cloprostenol (PG) and 20 mg estriol 24 h later. Calves (Japanese black cattle) were delivered 2 or 3 days after the DEX administration. SC calves were delivered by cesarean section (C-sec) when LOS was suspected by rectal palpation. Blood samples of recipients [vaginal delivery of SC (Vag): n = 13; C-sec of SC: n = 8; vaginal delivery of in vivo calves (Control): n = 4] were taken at Days 257 and 271 of pregnancy, and just before DEX (-2P), PG (-1P), and parturition (0P). Blood samples of calves were taken just after delivery to analyze cortisol level. The statistical significance was analyzed by the Steel-Dwass test. Birth weight of calves was the heaviest (P < 0.05) in C-sec (62 � 3 kg; n = 12); Vag calves (43 � 2 kg; n = 19) were also heavier (P < 0.05) than Control calves (29 � 2 kg; n = 9). E1 levels in Control calves remained low (<629 � 111 pg mL-1) until Day 271 and then increased progressively (>2156 � 599 pg mL-1). E1 levels tended to be lower in Vag (<1968 � 299 pg mL-1) and C-sec (<1268 � 385 pg mL-1) calves at -2P, -1P, and 0P; E1 levels in C-sec calves were significantly lower (P < 0.05) than in Control calves at -2P (512 � 85 pg/mL-1) and -1P (725 � 91 pg mL-1). The E2 level in Control calves increased and reached a plateau at -2P. Vag and C-sec calves showed lower E2 levels, except that the Vag level at 0P was similar to that in Control calves. The E2 level of C-sec calves (61.8 � 25.3 pg mL-1) at 0P was significantly lower (P < 0.05) than that of Control calves (247.5 � 102.8 pg mL-1). E1S levels in Vag and C-sec calves increased progressively from -2P to 0P, whereas the E1S level in Control calves increased at 0P. The E1S level in Vag calves (41.1 � 4.1 ng mL-1) was significantly higher (P < 0.05) than in Control calves (19.4 � 5.1 ng mL-1) at -1P. P4 levels decreased from -2P in Vag and Control calves, and from -1P in C-sec calves. The cortisol level in C-sec calves (60.1 � 19.1 ng mL-1) tended to be low compared with that in Vag (104.4 � 23.1 ng mL-1) and Control (93.4 � 15.0 ng mL-1) calves. This study revealed fetoplacental dysfunction of estrogen synthesis in the SC fetus during preparturition. Elevated E1S levels in recipients of the SC fetus, which correlated with high birth weight and agreed with previous reports for normal or plural pregnancy, might cause the reduction of E1 level. The comparable level of cortisol in Vag and Control calves indicated that SC calves had normal adrenal cortex function. Further analysis on placental estrogen synthesis and cortisol secretion in the SC fetus is necessary to clarify the cause of the prolonged gestation.

252 THE ROLE OF INSULIN-LIKE GROWTH FACTOR 1 (IGF-1) IN DEVELOPMENT OF AN ESTROGEN-ACTIVE DOMINANT FOLLICLE DURING THE FIRST FOLLICULAR WAVE POSTPARTUM IN DAIRY COWS

Recent studies have shown that IGF-1 is a crucial factor for ovarian follicular development in mammals. In postpartum (pp) dairy cows, plasma IGF-1 and estradiol (E2) levels in ovulatory cows at the first follicular wave pp are higher than in anovulatory cows. However, the plasma IGF-1 profile in an ovulatory or anovulatory dominant follicle (DF), which have different E2 production, at the first follicular wave pp have not yet been elucidated. Thus, we investigated the changing profile of plasma IGF-1 levels during first follicular wave pp. In 22 multiparous Holstein cows, blood samples were obtained 2 times/week from 4 weeks prepartum to 3 weeks pp, and the first follicular wave was monitored by ultrasound 2 times/week from 7 days pp to ovulatory phase. Detailed IGF-1 profiles in blood were determined during DF growth and maturation 4 times/day from 10 days pp to 7 days after the first ovulation in 5 ovulatory cows and to 20 days pp in 4 anovulatory cows; the data were analyzed by repeated measures ANOVA, and Student's t-test. There was no interaction between groups and time within the prepartum or the pp period. The ovulatory cows (n = 13/22) with an estrogen-active dominant (EAD: high plasma E2 level with peak) follicle showed higher IGF-1 levels than anovulatory cows (n = 9/22) with an estrogen-inactive dominant (EID: low plasma E2 level without peak) follicle during the prepartum (117 � 8 vs. 91 � 5 ng mL-1; P < 0.05) and the pp (91 � 4 vs. 64 � 4 ng mL-1; P < 0.001) period. Especially noteworthy, during the first follicular wave pp in ovulatory cows, the plasma IGF-1 levels were maintained at a high level until E2 levels increased, followed by an LH surge. We observed that the EAD follicle in ovulatory cows ovulated. To further examine the IGF-1 system in the intra-follicular environment, we used the EAD and EID follicles from ovaries of dairy cows obtained at a slaughterhouse. The EAD and EID follicles were classified on the basis of follicle diameter and E2 concentrations in follicular fluid (FF). The significant differences of factors between EAD and EID were analyzed by Student's t-test. The expression of IGF-1 mRNA was not detected in follicular cells in either EAD and EID, suggesting that IGF-1 in FF is mainly derived from liver. The free IGF-1 levels in FF in EAD (4.8 � 0.5 ng mL-1) were higher than those in EID (2.7 � 0.1 ng mL-1; P < 0.05). In addition, the expression of type 1 IGF receptor (IGFR-1) mRNA in EAD was higher than hat in EID (P < 0.0001). From the results of the present study, it is apparent that the EAD follicle during the first follicular wave pp in ovulatory cows sufficiently expressed IGFR-1, and a liver-derived IGF-1 stimulates E2 production in the follicle to ovulate. In conclusion, our data suggest that a high concentration of IGF-1, secreted from the liver, during the peripartum period may be one of important factors for the appearance of an ovulatory follicle during the first follicular wave pp cows.

Insulin Signaling in Arteries Prevents Smooth Muscle Apoptosis

OBJECTIVE

Insulin is an antiapoptotic factor of cultured vascular cells, but it is not clear whether it also exerts antiapoptotic effects on vascular cells in vivo. We studied insulin receptor signaling in the arteries of normal and diabetic rats to establish whether insulin exhibits antiapoptotic activity toward vascular smooth muscle cells in vivo as well as in vitro.

METHODS AND RESULTS

Western blot analysis and real-time polymerase chain reaction revealed alpha- and beta-subunits of the insulin receptor in association with insulin receptor substrate-1 and phosphatidylinositol 3-kinase in the media of the aorta and carotid artery. The insulin receptor signaling pathway was partially activated under physiological conditions, further activated by intravenous insulin injection, and was attenuated in streptozotocin-induced diabetic rats. Lipopolysaccharide injection induced more apoptosis of vascular smooth muscle cells in diabetic rats than in control rats, whereas insulin prevented apoptosis in the aortic wall. An in vitro study suggested that the antiapoptotic effect of insulin was mediated by phosphatidylinositol 3-kinase.

CONCLUSIONS

Insulin is an antiapoptotic factor of vascular smooth muscle cells in vitro and in vivo. Decreased insulin activity on the artery may increase smooth muscle cell death and cause unstable plaque formation associated with diabetes.

99mtc-labeled mannosyl-neoglycoalbumin for sentinel lymph node identification

99mTc-labeled mannosyl-neoglycoalbumin (NMA) was prepared and evaluated as a radiopharmaceutical for sentinel lymph node (SLN) identification, since 99mTc-labeled human serum albumin (HSA) rapidly cleared from injection sites. NMA was conjugated with 6-hydrazinopyridine-3-carboxylic acid (HYNIC) and reacted with [99mTc](tricine)2 to prepare [99mTc](HYNIC-NMA)(tricine)2. After subcutaneous injection of [99mTc](HYNIC-NMA)(tricine)2 from murine foot pad, radioactivity levels in the popliteal and lumbar lymph nodes, the injection site and other tissues were compared with those of [99mTc](HYNIC-HSA)(tricine)2 and 99mTc-labeled colloidal rhenium sulfate ([99mTc]colloid). [99mTc](HYNIC-NMA)(tricine)2 demonstrated significantly higher radioactivity levels in the popliteal lymph node, the SLN in this model, than did [99mTc](HYNIC-HSA)(tricine)2 and [99mTc]colloid at 0.5, 1, and 6 h post-injection. [99mTc](HYNIC-NMA)(tricine)2 showed a dose-dependent decrease in the popliteal accumulation while the radioactivity levels in the blood, liver and spleen increased with an increase in the molar dose of NMA. [99mTc]colloid registered a decrease in the radioactivity levels in the popliteal lymph node, blood, liver, and spleen with dilution. However, the radioactivity levels at the injection site increased with dilution of [99mTc] colloid. Both [99mTc](HYNIC-NMA)(tricine)2 and [99mTc](HYNIC-HSA)(tricine)2 showed the radioactivity levels at the injection site similar each other. These findings indicated that an addition of a macrophage binding function to 99mTc-labeled HSA provided high and selective accumulation of the radioactivity in the SLN without affecting the elimination rate from the injection site. Such characteristics render [99mTc](HYNIC-NMA)(tricine)2 attractive as a radiopharmaceutical for SLN identification. This study also demonstrated that the number of non-radiolabeled colloidal particles and the molar dose of mannosylated compounds play a crucial role in the SLN accumulation.

Anomalously hindered E2 strength B(E2;2+(1)-->0+) in 16C

The electric quadrupole transition from the first 2(+) state to the ground 0(+) state in 16C is studied through measurement of the lifetime by a recoil shadow method applied to inelastically scattered radioactive 16C nuclei. The measured mean lifetime is 77+/-14(stat)+/-19(syst) ps. The central value of mean lifetime corresponds to a B(E2;2+(1)-->0(+)) value of 0.63e(2) fm(4), or 0.26 Weisskopf units. The transition strength is found to be anomalously small compared to the empirically predicted value.

Induction of intestinal ATP-binding cassette transporters by a phytosterol-derived liver X receptor agonist

The nuclear receptors liver X receptor (LXR) alpha and LXRbeta serve as oxysterol receptors and regulate the expression of genes involved in lipid metabolism. LXR activation induces the expression of ATP-binding cassette (ABC) transporters, such as ABCG5 and ABCG8, which inhibit intestinal absorption of cholesterol and phytosterols. Although several synthetic LXR agonists have been generated, these compounds have limited clinical application, because they cause hypertriglycemia by inducing the expression of lipogenic genes in the liver. We synthesized derivatives of phytosterols and found some of them to act as LXR agonists. Among them, YT-32 [(22E)-ergost-22-ene-1alpha,3beta-diol], which is related to ergosterol and brassicasterol, is the most potent LXR agonist. YT-32 directly bound to LXRalpha and LXRbeta and induced the interaction of LXRalpha with cofactors, such as steroid receptor coactivator-1, as effectively as the natural ligands, 22(R)-hydroxycholesterol and 24(S),25-epoxycholesterol. Although the nonsteroidal synthetic LXR agonist T0901317 induced the expression of intestinal ABC transporters and liver lipogenic genes, oral administration of YT-32 selectively activated intestinal ABC transporters in mice. Unlike T0901317 treatment, YT-32 inhibited intestinal cholesterol absorption without increasing plasma triglyceride levels. The phytosterol-derived LXR agonist YT-32 might selectively modulate intestinal cholesterol metabolism.

Effects of Helicobacter pylori infection on gastric acid secretion and serum gastrin levels in Mongolian gerbils

BACKGROUND AND AIMS

Body gastritis caused by Helicobacter pylori infection appears to inhibit gastric acid secretion. The aim of this study was to determine the effects of H pylori infection on gastric acid secretion and clarify its mechanisms with reference to interleukin 1beta (IL-1beta).

METHODS

(1) Mongolian gerbils were inoculated orally with H pylori. Before, six, and 12 weeks after inoculation, serum gastrin levels, gastric acid output, and IL-1beta mRNA levels in the gastric mucosa were determined. Pathological changes were also determined according to the updated Sydney system. (2) Effects of recombinant human IL-1 receptor antagonist (rhIL-1ra) on gastric acid output and serum gastrin levels were also determined.

RESULTS

(1) Scores for activity and inflammation of gastritis and serum gastrin levels were significantly increased, and gastric acid output was significantly decreased six and 12 weeks after inoculation with H pylori. IL-1beta mRNA levels in the gastric mucosa were also elevated six and 12 weeks after inoculation with H pylori. (2) Acid output and serum gastrin levels in the infected groups returned to control levels after rhIL-1ra injection.

CONCLUSIONS

Gastric acid secretion is decreased and serum gastrin levels are increased in Mongolian gerbils infected with H pylori. This change in gastric acid secretion appears to be mediated by IL-1beta induced by H pylori infection.

Intra-abdominal desmoplastic small round cell tumor (IDSRT)

Intra-abdominal desmoplastic small round cell tumor (IDSRT) is a rare neoplasm that develops in the abdominal cavity in young people. We experienced a 27-year-old man who visited with ascites of unknown cause. Compression of the colon was found by barium enema examination. On colonoscopic examination, diffuse white elevated lesions, about 5 mm in diameter, surrounded by rubedo, so-called aphthoid lesions, were also observed. IDSRT was diagnosed by biopsy at laparotomy, and chemotherapy with cyclophosphamide, etoposide, doxorubicin, and cisplatin was performed. The tumors shrank temporarily (partial response), but subsequently grew in size again. The patient died during the second course of chemotherapy after relapse. We present one case report, together with a review of the literature.

Peptic ulcer recurrence during maintenance therapy with H2-receptor antagonist following first-line therapy with proton pump inhibitor

We investigated the peptic ulcer recurrence rates during maintenance therapy with H2-receptor antagonists (H2RAs) following first-line therapy with a proton pump inhibitor (PPI). Patients with gastric ulcer (GU) or duodenal ulcer (DU) were enrolled in this study; 583 eligible patients (GU, 325; DU, 258) were administered lansoprazole (30 mg/day for 8 weeks for GU, and the same dosage for 6 weeks for DU) as first-line therapy, and a half dose of H2RA as maintenance therapy for 12 months. Endoscopic photographs were taken before administration and after 8 (GU) and 6 (DU) weeks of lansoprazole administration. Ulcer stage was evaluated using the classification of Sakita and Miwa. Endoscopic examinations were performed 6 months or 12 months after the start of maintenance therapy or when a recurrence was suspected because of the appearance of subjective symptoms. The healing rates for GU and DU patients after completion of lansoprazole therapy were 79% in both groups, while the S2-stage healing rates were 18% and 31%, respectively. At 1 year after the start of maintenance therapy, the recurrence rates were 25% for GU and 39% for DU patients. In DU patients, the recurrence rates from S1-stage and S2-stage were 49% and 20%, respectively (P = 0.004), but no significant difference was found between these rates in GU patients. The recurrence rates in H. pylori-positive patients before lansoprazole administration were 27% for GU and 43% for DU patients. We concluded that the maintenance therapy with a half-dose of H2RA following PPI therapy was insufficient to prevent recurrences of GU and DU.

Effect of genotypic differences in CYP2C19 on cure rates for Helicobacter pylori infection by triple therapy with a proton pump inhibitor, amoxicillin, and clarithromycin

BACKGROUND

Proton pump inhibitors such as omeprazole and lansoprazole are mainly metabolized by CYP2C19 in the liver. The therapeutic effects of proton pump inhibitors are assumed to depend on CYP2C19 genotype status.

OBJECTIVE

We investigated whether CYP2C19 genotype status was related to eradication rates of H pylori by triple proton pump inhibitor-clarithromycin-amoxicillin (INN, amoxicilline) therapy and attempted to establish a strategy for treatment after failure to eradicate H pylori.

METHODS

A total of 261 patients infected with H pylori completed initial treatment with 20 mg of omeprazole or 30 mg of lansoprazole twice a day, 200 mg of clarithromycin three times a day, and 500 mg of amoxicillin three times a day for 1 week. CYP2C19 genotypes of patients were determined with polymerase chain reaction-restriction fragment length polymorphism analysis. Patients without eradication after initial treatment were retreated with 30 mg of lansoprazole four times daily and 500 mg of amoxicillin four times daily for 2 weeks.

RESULTS

Eradication rates for H pylori were 72.7% (95% confidence interval, 64.4%-81.8%), 92.1% (confidence interval, 86.4%-97.3%), and 97.8% (confidence interval, 88.5%-99.9%) in the homozygous extensive, heterozygous extensive, and poor metabolizer groups, respectively. Thirty-four of 35 patients without eradication had an extensive metabolizer genotype of CYP2C19. Nineteen of those patients were infected with clarithromycin-resistant strains of H pylori. However, there were no amoxicillin-resistant strains of H pylori. Re-treatment of H pylori infection with dual high-dose lansoprazole-amoxicillin therapy succeeded in 30 of 31 patients with extensive metabolizer genotype of CYP2C19.

CONCLUSION

The majority of patients without initial eradication of H pylori had an extensive metabolizer CYP2C19 genotype but were successfully re-treated with high doses of lansoprazole and an antibiotic to which H pylori was sensitive, such as amoxicillin, even when the patients were infected with clarithromycin-resistant strains of H pylori.

Detection of dissection and remodeling of atherosclerotic lesions in rabbits after balloon angioplasty by magnetic-resonance imaging

OBJECTIVE

To assess the usefulness of magnetic-resonance imaging (MRI) for monitoring acute changes after angioplasty of preexisting lesions in rabbits with basal lesions similar to those observed in humans.

METHODS

A combination of Fogarty balloon injury (1 week after initiation of diet) and a mildly hypercholesterolemic diet (0.2% cholesterol and 5% peanut oil) was used to promote the rapid formation of atherosclerotic lesions in 16 New Zealand white rabbits. After 5 months of the diet, angioplasty was performed on these lesions with a Grüntzig catheter in both iliac arteries and the abdominal aorta. MRI was used to monitor the initial formation of lesions after 3 and 5 months of the diet, and 2 days, 2 weeks, and 1 and 2 months after angioplasty.

RESULTS

The combination of early Fogarty injury and mildly hypercholesterolemic diet induced fibroproliferative lesions similar to type Vb atherosclerotic lesions seen in humans. Angioplasty induced deep dissections at the shoulders of lesions in the majority of animals. These dissections often extended into the media. The cellular, proliferative response after angioplasty was localized and limited to sites of dissection. A significant increase in area of arterial wall was observed after angioplasty at sites of dissection without any loss of lumen. In contrast, proximal and distal to the sites of injury, there was no change in wall area but a transient reduction in lumen area.

CONCLUSIONS

Comparison of MRI results with histology confirmed that changes in the wall and lumen, including small linear dissections in the lesions and arterial remodeling, are detectable by MRI.

A patient with thrombotic microangiopathy accompanied by glomerular subendothelial electron dense deposits

A 50-year-old woman presented with thrombocytopenia, microangiopathic hemolytic anemia, and nephrotic syndrome. Although a high level of circulating immune complexes, mild hypocomplementemia, and the antinuclear antibody also were present, the criteria for collagen disease were not fulfilled. Renal biopsy demonstrated a typical thrombotic microangiopathy (TMA) involving glomeruli. There also were electron-dense deposits located just beneath the original glomerular basement membrane in the dilated subendothelial space, thought to be immune complexes following positive IgG, C1q and C3 staining on an immunofluorescent study. Corticosteroid therapy rapidly ameliorated her hematologic abnormalities and proteinuria and normalized the immunologic data. These findings strongly suggest that the TMA in this patient was induced by immune complex-associated mechanisms.

Preoperative diagnosis of ileal lipoma by endoscopic ultrasonography probe

The occurrence of tumor in the small intestine is relatively rare. It has been demonstrated that lipoma of the ileum is a cause of intussusception. We report a 59-year-old man admitted to our hospital for lower abdominal pain. Diagnosis of intussusception was made by abdominal x-ray and ultrasonography. Enema contrast studies revealed ileocolic intussusception. Colonoscopy revealed a tumor with an submucosal tumor (SMT)-like head and coil-spring appearance in the ascending colon. Endoscopic ultrasonography (EUS) revealed a hyperechoic submucosal lesion with features compatible with lipoma. Subsequently, this was confirmed histopathologically after resection. To our knowledge, this is the first report of preoperative diagnosis of ileal lipoma by EUS.

Alterations of GTP-binding proteins (Gsalpha and Gq/11alpha) in gastric smooth muscle cells from streptozotocin-induced and WBN/Kob diabetic rats

We investigated possible impairment of the signal transduction system in gastric myocytes of streptozotocin-induced diabetic (STZ) and spontaneous diabetic WBN/Kob (WBN/Kob) rats. Gastric motility 10 weeks after the onset of diabetes mellitus was significantly reduced in both diabetic rats compared with control, and the decreased motility was not recovered by the administration of insulin to maintain normal blood glucose levels. There was no significant difference between both types of diabetic rats and control rats in total number of [3H]quinuclidinyl benzilate ([3H]QNB) binding sites (Bmmax: 545-587 fmol/mg protein) on gastric smooth muscle cell membranes or in the affinity of [3H]QNB for the binding sites (Kd: 0.06-0.07 nM). Immunoblot analysis using polyclonal anti-G-protein antibodies indicated increased expression of Gsalpha in gastric smooth muscle cell membranes, but no significant change in Gialpha or Gq/11alpha expression in STZ rats, and decreased expression of Gq/11alpha with no significant change in Gsalpha and Gialpha in WBN/Kob rats. The cAMP production in gastric smooth muscle cell membranes was augmented in the absence and presence of 100 microM isoproterenol, and 100 microM forskolin in STZ rats, whereas no significant change of cAMP production was observed in WBN/Kob rats irrespective of the presence of the stimulants. These findings suggest that long-standing diabetes may induce alterations in signal transduction at downstream receptors in gastric myocytes, resulting in the impairment of gastric motility, although the mechanism of reduced contractile activity may differ between STZ and WBN/Kob rats.

Ovarian mucinous cystadenocarcinoma as a cause of Zollinger-Ellison syndrome: report of a case and review of the literature

Gastrin producing ovarian tumor is a rare cause of the Zollinger-Ellison syndrome. We report the case of an ovarian carcinoma showing increased plasma gastrin concentration. A 60-yr-old woman presented with epigastric pain and diarrhea. Physical examination showed a large mass in the lower abdomen. Computed tomography revealed a large multilocular ovarian cyst. Upper gastrointestinal endoscopy examination showed multiple ulcerations of the stomach and duodenum. The plasma gastrin level was 1500 pg/ml. No tumors were found in the pancreas and duodenum, and salpingo-oophorectomy was performed. Histologic examination revealed a mucinous tumor of borderline malignant potential. Immunoperoxidase studies for gastrin showed many gastrin-producing cells within the epithelium of the tumor. There have been 11 cases (including our patient) of gastrin-producing ovarian tumor reported in the literature. We review here the relevant literature. Although ovarian gastrinoma is extremely rare, it should be considered as a possible cause of the Zollinger-Ellison syndrome in women.

Relationship between Helicobacter pylori infection and smoking and drinking habits

BACKGROUND

Helicobacter pylori is a major cause of various gastroduodenal diseases. Some risk factors related to H. pylori infection have been reported; however, studies on the relationship between H. pylori infection and smoking or drinking habits have given conflicting results. In the present study, these relationships were investigated by collecting sera and information from 8837 subjects.

METHODS

Serum H. pylori immunoglobulin G antibody was measured by an enzyme-linked immunoassay. In addition to sex and age, information on smoking and drinking habits was collected by questionnaire. Age- and sex-adjusted odds ratios (95% confidence interval) of smoking and alcohol consumption were calculated for H. pylori seropositivity using logistic regression models.

RESULTS

Current smokers had a 0.82 (0.74-0.91)-fold greater risk of H. pylori seropositivity than those who had never smoked. Current cigarette consumption showed a dose-dependently negative association with H. pylori seropositivity, and the association between smoking and H. pylori infection was strong in younger subjects. Current drinkers had a 0.88 (0.79-0.98)-fold greater risk of H. pylori seropositivity than those who had never drunk alcohol. The volume of alcohol consumed showed a negative association with H. pylori seropositivity.

CONCLUSIONS

In the current study, smoking was negatively associated with H. pylori infection. The risk of H. pylori seropositivity decreased linearly with cigarette consumption per day. Increased gastric acidity in the stomach through smoking may be a cause of the dose-dependently negative association between H. pylori and smoking. Drinking was negatively and dose-dependently associated with H. pylori positivity, although the effect of drinking was weaker than that of smoking.

A patient with undifferentiated carcinoma of gallbladder presenting with hemobilia

Hemobilia is relatively rare among hemorrhages in the digestive tract, and hemobilia caused by tumors of the biliary tract is particularly rare. We treated a 74-year-old-man with undifferentiated carcinoma of the gallbladder presenting with hemobilia. During hospitalization for neurogenic bladder at the Department of Urology, he showed progressive anemia. Since hemorrhage in the digestive tract was suspected, endoscopy of the upper gastrointestinal tract was performed, and bleeding from the papilla of Vater was observed. On ultrasound examination, findings were indicative of cholecystic cancer, and hemorrhage from the cystic duct was found on percutaneous transhepatic cholangioscopy. On perioral cholecystoscopy, however, masses of coagulated blood were found only in the gallbladder. Abnormalities such as dense staining of tumors or extravasation were not found on angiography. The patient died of hepatic failure due to rapid invasion of the liver by the tumor, associated with biliary infection and disseminated intravascular coagulation. At autopsy, a nodal tumor was found in the gallbladder, and the cavity of the gallbladder was filled with coagulated masses of blood. Direct invasion of the tumor to the liver, diaphragm, and transverse colon was found. The histopathological diagnosis was undifferentiated carcinoma (pleomorphic large-cell type).

Relation between interleukin-1beta messenger RNA in gastric fundic mucosa and gastric juice pH in patients infected with Helicobacter pylori

The effects of Helicobacter pylori infection on gastric acid secretion has not been clarified. The aim of this study was to elucidate the effects of H. pylori infection on gastric juice pH in relation to gene expression of interleukin-1beta (IL-1beta), which is reported to inhibit gastric acid secretion. Gastric juice pH and serum gastrin levels were measured in patients with peptic ulcer disease. The amount of IL-1beta mRNA in gastric fundic gland mucosa was also measured by a competitive reverse transcription-polymerase chain reaction method. These parameters were determined before and after treatment with lansoprazole and amoxicillin. Before treatment a significant positive relation was observed between the amount of IL-1beta mRNA in gastric fundic gland mucosa and gastric juice pH. After treatment significant decreases in the amount of IL-1beta mRNA, gastric juice pH, and serum gastrin levels were observed in patients with eradication of H. pylori, whereas no significant changes were observed in patients without eradication. These results suggest that H. pylori infection induces IL-1beta and suppresses acid secretion, resulting in increases in gastric juice pH and serum gastrin levels. Eradication of H. pylori decreases IL-1beta induction, resulting in an increase in gastric juice acidity and normalization of serum gastrin levels.

Protein-losing enteropathy caused by mesenteric venous thrombosis with protein C deficiency

A 64-year-old man presented with leg edema and hypoproteinemia. His alpha-1 antitrypsin clearance rate of 174 mL/day indicated the presence of protein-losing enteropathy (PLE). Computed tomographic scans demonstrated thickened ileal wall and mesenteric edema. Angiography revealed occlusion in a peripheral branch of the superior mesenteric vein. Furthermore, both the patient and his son had low protein C levels. The patient was treated successfully with partial resection of the ileum. Histologic examination of the resected ileum revealed multiple erosions and submucosal fibrosis with organized venous thrombi in the mesenteric veins. This is the first case report of PLE caused by mesenteric venous thrombosis, and our findings suggest that serum protein was lost through erosion of the ileum caused by ischemia due to mesenteric venous thrombosis.

Morphologic abnormalities in the brain of chronically hemodialyzed patients without cerebrovascular disease

In this study, the authors evaluated the cerebral atrophy in 56 chronic hemodialyzed patients, who did not have clinical episodes or radiologic findings of cerebrovascular diseases, and 42 controls. Using computed tomography (CT) images, brain atrophy index (BAI), the proportion of subarachnoidal plus ventricular space in the cranial cavity, and ventricular area index (VAI), percent area of ventricle in the brain, were calculated. CT of the brain demonstrated an age-dependent increase in BAI in both hemodialyzed patients and controls. BAI and VAI were greater in hemodialyzed patients than healthy controls and the difference was significant at ages under 60 years in BAI and at ages less than 50 years in VAI. The atrophy of the frontal parts of the brain in patients on hemodialysis for 10 years or more was significantly greater than in patients dialyzed for less than 10 years. There was a significant negative correlation between BAI or VAI and hematocrit. These findings indicate that renal failure or hemodialysis itself might cause cerebral atrophy, and that the cerebral atrophy is more prominent in patients on hemodialysis for a long duration and with low hematocrit.

Successful treatment of percutaneous transhepatic papillary dilation in patients with obstructive jaundice due to common bile duct stones after Billroth II gastrectomy: report of two emergent cases

Successful treatment of two patients with obstructive jaundice due to choledocholithiasis after Billroth II gastrectomy was performed by elimination of stones by percutaneous transhepatic balloon dilatation of the sphincter of Oddi. Patient 1 was an 82-year-old man and Patient 2 was a 73-year-old man. Both patients presented with obstructive jaundice. The papilla was not observed in either patient because of previous Billroth II gastrectomy. Because an endoscopic approach was impossible, percutaneous transhepatic cholangiodrainage (PTCD) was performed to alleviate jaundice. Choledocholithiasis was treated as follows: The sphincter of Oddi was dilated by percutaneous transhepatic balloon, and stone particles were removed from the papilla with a stone-eliminating balloon catheter via the same route of PTCD. This method is less invasive than the percutaneous transhepatic cholangioscopic method, and the use of existing appliances such as a balloon for papillary dilation is possible. Hence, this method appears to be an effective and simple method for the treatment of choledocholithiasis after gastrectomy that is difficult to treat endoscopically.

alphaPIX nucleotide exchange factor is activated by interaction with phosphatidylinositol 3-kinase

p21-activated kinase (PAK) is a common effector protein of the small GTPases Cdc42 and Rac, leading to the activation of downstream mitogen activated protein kinases. PAK also mediates polarized cytoskeletal changes induced by these GTPases. The recently identified PAK-interacting exchange factor (PIX) acts as a guanine nucleotide exchange factor on Rac, and colocalizes with PAK in a focal complex, but little is known about the associated signaling cascades, including upstream activators of PIX. In this study, we show that one of the isoforms of PIX, alphaPIX, is activated by signaling cascades from the platelet-derived growth factor (PDGF) receptor and EphB2 receptor, and from integrin-induced signaling through phosphatidylinositol 3-kinase (PI3-kinase). alphaPIX is activated by forming a complex with these receptors either via association with PAK and Nck, or direct association with the p85 regulatory subunit of PI3-kinase. Synthetic phosphoinositide and membrane targeted PI3-kinase augmented the alphaPIX activity in vivo. In Xenopus, aggregates of mesodermal cells derived from embryos microinjected with alphaPIX significantly increased the peripheral spreading on fibronectin substrate in response to PDGF through PI3-kinase. These results indicate that alphaPIX is activated by PI3-kinase, and is involved in the receptor mediated signaling leading to the activation of the kinase activity of PAK, and the migration of mesodermal cells on extracellular matrix.

Role of the vasopressin V(1) receptor in regulating the epithelial functions of the guinea pig distal colon

Vasopressin has a wide spectrum of biological action. In this study, the role of vasopressin in regulating electrolyte transport in the colon was elucidated by measuring the short-circuit current (I(sc)) as well as the Na(+), K(+), and Cl(-) flux in a chamber-mounted mucosal sheet. The cytosolic Ca(2+) concentration ([Ca(2+)](i)) was also measured in fura 2-loaded cells by fluorescence imaging. Serosal vasopressin decreased I(sc) at 10(-9) M and increased I(sc) at 10(-7)-10(-6) M. The decrease in I(sc) was accompanied by two effects: one was a decrease in the amiloride-sensitive Na(+) absorption, whereas the other was an increase in the bumetanide-sensitive K(+) secretion. The increase in I(sc) was accompanied by an increase in the Cl(-) secretion that can be inhibited by serosal bumetanide or mucosal diphenylamine-2-carboxylate. Vasopressin caused an increase in [Ca(2+)](i) in crypt cells. These responses of I(sc) and the [Ca(2+)](i) increase in crypt cells were all more potently inhibited by the vasopressin V(1) receptor antagonist than by the V(2) receptor antagonist. These results suggest that vasopressin inhibits electrogenic Na(+) absorption and stimulates electrogenic K(+) and Cl(-) secretion. In all of these responses, the V(1) receptor is involved, and the [Ca(2+)](i) increase may play an important role.

Preservative treatment for biliobiliary fistula

Biliobiliary fistula is thought to be a rare type of internal biliary fistula. A 68-year-old man presented to our hospital with complaints of jaundice and general malaise. Endoscopic retrograde cholangiography was performed, but the gallbladder was not imaged. Mirizzi's sign was observed in the common hepatic duct. During the course of evaluating this inpatient, imaging revealed that a gallstone was extruded to the right hepatic duct. After incision of the papilla, stones in the bile duct were subjected to mechanical lithotripsy and were extracted. As a result of bile duct decompression, the biliobiliary fistula was closed completely 2 months later.

Effects of clarithromycin on the metabolism of omeprazole in relation to CYP2C19 genotype status in humans

BACKGROUND AND PURPOSE

A triple therapy with omeprazole, amoxicillin (INN, amoxicilline), and clarithromycin is widely used for the eradication of Helicobacter pylori. Omeprazole and clarithromycin are metabolized by CYP2C19 and CYP3A4. This study aimed to elucidate whether clarithromycin affects the metabolism of omeprazole.

METHODS

After administration of placebo or 400 mg clarithromycin twice a day for 3 days, 20 mg omeprazole and placebo or 400 mg clarithromycin were administered to 21 healthy volunteers. Plasma concentrations of omeprazole and clarithromycin and their metabolites were determined before and 1, 2, 3, 5, 7, 10, and 24 hours after dosing. CYP2C19 genotype status was determined by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Subjects were classified into three groups on the basis of PCR-RFLP analyses for CYP2C19: homozygous extensive metabolizer group (n = 6), heterozygous extensive metabolizer group (n = 11), and poor metabolizer group (n = 4). Mean area under the plasma concentration-time curves from 0 to 24 hours (AUC) of omeprazole in the homozygous extensive metabolizer, heterozygous extensive metabolizer, and poor metabolizer groups were significantly increased by clarithromycin from 383.9 to 813.1, from 1001.9 to 2110.4, and from 5589.7 to 13098.6 ng x h/mL, respectively. There were significant differences in the mean AUC values of clarithromycin among the three groups.

CONCLUSION

Clarithromycin inhibits the metabolism of omeprazole. Drug interaction between clarithromycin and omeprazole may underlie high eradication rates achieved by triple therapy with omeprazole, amoxicillin, and clarithromycin.

Up-regulation of H2 receptor and adenylate cyclase in rabbit parietal cells during prolonged treatment with H2-receptor antagonists

Intragastric hyperacidity occurs after abrupt withdrawal of histamine H2-receptor antagonists, and the prolonged administration of these agents induces tachyphylaxis of the inhibitory effects on gastric acid secretion. We examined the effect of the prolonged administration of H2-receptor antagonists on the H2-receptor signaling system in parietal cells isolated from rabbits that had received H2-receptor antagonists for 14 days. [125I]aminopotentidine (APT) binding sites to H2 receptors in parietal cell membranes were increased without any significant change in the affinity for [125I]APT. The expression of Gs(alpha), guanosine triphosphate (GTP)-binding protein coupled to H2 receptor, was slightly increased. Basal as well as GTP- or histamine-stimulated cAMP production was increased, but no significant change was observed in the presence of an H2-receptor antagonist. The up-regulation of the H2 receptor and adenylate cyclase appeared to cause hypersecretion of acid after withdrawal of H2-receptor blockade.

Primary small cell carcinoma of the esophagus with achalasia in a patient in whom pro-gastrin-releasing peptide and neuron-specific enolase levels reflected the clinical course during chemotherapy

We report a case of primary small cell carcinoma of the esophagus in a patient with achalasia in whom pro-gastrin-releasing peptide (ProGRP) and neuron-specific enolase (NSE) levels were measured. Although chemotherapy markedly reduced the size of the primary tumor and lymph node metastases, it had no effect on liver metastases. The tumor marker levels decreased after chemotherapy as the primary tumor and lymph node metastases decreased in size, and they increased as the liver metastases enlarged. However, there was a discrepancy between the levels of ProGRP and NSE during the patient's clinical course. We demonstrate the usefulness of measuring ProGRP and NSE levels to assess the effect of chemotherapy in patients with esophageal small cell carcinoma.