18F alpha-methyl tyrosine PET studies in patients with brain tumors

We have developed 18F-labeled alpha-methyl tyrosine (FMT) for PET imaging. The aim of this study was to evaluate the clinical application potential of FMT for patients with brain tumors.

METHODS

Eleven healthy volunteers and 20 patients with brain tumors were injected with 185 MBq (5 mCi) FMT. In 3 healthy volunteers, whole-body imaging and urinary and plasma analysis were conducted for the assessment of the biodistribution of FMT. The normal range of cortical standardized uptake value (SUV) as a reference for comparing tumor SUV of FMT was estimated by using PET data obtained at 30 min postinjection in 8 healthy volunteers. Dynamic PET scans were conducted for 100 min in 4 healthy volunteers and for 30 min in 15 patients with brain tumors. The 10-min static images in another 4 volunteers and all patients were obtained at 30 min postinjection. In 13 patients, FMT uptake in the brain tumor was compared with 18F-fluorodeoxyglucose (FDG). Tumor-to-normal cortex count (T/N) ratio and tumor-to-white matter count (T/W) ratio and SUVs of brain tumors were determined on FMT and FDG PET images.

RESULTS

Approximately 1480 MBq (40 mCi) FMT were produced in one radiosynthesis. Percentage injected dose (%ID) of FMT in the brain ranged from 2.8% to 4.9%, and approximately 50%ID of FMT was excreted in urine during 60 min postinjection, of which 86.6% was unmetabolized FMT. A faint physiological brain uptake with SUV of 1.61 +/- 0.32 (mean +/- SD, n = 8) was observed in healthy volunteers. Tumor SUV of FMT ranged from 1.2 to 8.2, with mean value of 2.83 +/- 1.57 (n = 23), which was significantly higher than that of the cortical area in healthy volunteers (P < 0.01). T/N and T/W ratios of FMT were significantly higher than those of FDG (2.53 +/- 1.31 versus 1.32 +/- 1.46, P < 0.001; 3.99 +/- 2.10 versus 1.39 +/- 0.65, P < 0.0001, respectively).

CONCLUSION

FMT, like other radiolabeled amino acids, can provide high-contrast PET images of brain tumors.

Age-related bone loss: relationship between age and regional bone mineral density

We assessed the changes in regional bone mineral density according to age and examined the relationship between various regional bone mineral densities. The study was conducted in 985 Japanese women divided into < 50-years group (n = 435) and > or = 50 years group (n = 550). The total body bone mineral density and that of the head, arm, leg, thoracic (T)-spine, lumbar (L)-spine, ribs, and pelvis were measured using dual energy x-ray absorptiometry. There was a significant generalized reduction of bone mineral density in all regions after the age of 50 years. The most marked age-related decrease was observed in the L-spine. Bone mineral densities in all regions significantly correlated to each other in both age groups, but the degree of significance varied among regions. The relationship between bone mineral density of the L-spine and that of T-spine regions was the most significant in both groups. In the < 50-years group, the correlation between bone mineral density of the pelvis and that of L-spine and T-spine was the highest, followed by that between the pelvis and the leg. On the other hand, in the > or = 50-years group, the correlation between bone mineral density of the pelvis and that of the leg was the highest, but not the L-spine or T-spine. Since spine measurements are affected by vertebral deformity and/or aortic calcification, our findings suggest the pelvis may be a useful region for screening measurements of bone mineral density, especially in older women.

Preventive effects of an antiallergic drug, pemirolast potassium, on restenosis after percutaneous transluminal coronary angioplasty

BACKGROUND

We recently confirmed that pemirolast potassium, an antiallergic agent, markedly inhibits migration and proliferation of vascular smooth muscle cells. It has also been reported that pemirolast inhibits intimal hyperplasia in animal experiments.

METHODS AND RESULTS

To elucidate the preventive effects of pemirolast on restenosis after percutaneous transluminal coronary angioplasty (PTCA), 227 patients were enrolled in this prospective, randomized trial. A total of 205 patients who were compatible with the protocol were analyzed (pemirolast group, 104 patients with 140 lesions; control group, 101 patients with 133 lesions). Patients in the pemirolast group received 20 mg/d of pemirolast from 1 week before PTCA until the time of follow-up angiography (4 months after PTCA). Angiographic restenosis was defined as diameter stenosis >/=50% at follow-up. Restenosis rates were significantly lower in the pemirolast group than in the control group (24.0% vs 46.5% of patients, 18.6% vs 35.3% of lesions, P <.01, respectively). During 8 months of follow-up, there were no coronary events (death, myocardial infarction, coronary artery bypass surgery, or repeated PTCA) in 81.7% of the pemirolast group and in 63.4% of the control group (P =.013).

CONCLUSIONS

This study suggested that pemirolast would be useful in the clinical setting to prevent restenosis after PTCA.

Double-contrast radiographic assessment of lupus-associated enteropathy

PURPOSE

To describe the double-contrast radiographic features of lupus-associated enteropathy.

MATERIALS AND METHODS

Six patients with systemic lupus erythematosus involving the small bowel were assessed by double-contrast radiography of the duodenum and small intestine, with reference to clinical manifestations and jejunoscopic findings.

RESULTS

Lupus-associated enteropathy could be categorized into two types: acute onset enteritis in four patients and protein-losing enteropathy with hyperlipidaemia in two patients. The former group presented with irregular thickening and spiculation in the folds of the multiple segments of the duodenum to the terminal ileum, and they were frequently accompanied by thumbprinting, suggestive of ischaemic change. The latter group was characterized by mildly thickened folds with multiple submucosal nodules in the upper portion of the jejunum. In one patient from this group, jejunal biopsy demonstrated lymphangiectasia. Both groups were successfully treated by high-dose prednisolone. Follow-up radiography in the former group showed a complete improvement within 2-7 weeks, whereas radiographic abnormalities in the latter remained even after 2 months.

CONCLUSIONS

Lupus-associated enteropathy cases may be divisible into two types; an acute ischaemic enteritis type and a protein-losing enteropathy type, each presenting distinct radiographic features.

Treatment of herpes simplex esophagitis in an immunocompetent patient with intravenous acyclovir: a case report and review of the literature

A 35-yr-old, immunocompetent male was admitted complaining of severe odynophagia. He was diagnosed as having herpes simplex esophagitis and was started on intravenous acyclovir 5 mg/kg every 8 h on the day of admission. His response was dramatic. Within 24 h he was virtually asymptomatic. Acyclovir therapy in immunocompetent adults with esophagitis has been described in only a handful of cases in the literature, although the therapy is well established in immunocompromised patients. We review the English literature and discuss the efficacy of the therapy. Acyclovir therapy may be beneficial in immunocompetent patients with particularly severe odynophagia.

Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa isolation from pharyngeal swab cultures among the Japanese elderly at admission to a geriatric hospital

The isolation rate of Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa from pharyngeal swab cultures in the Japanese elderly was studied at admission to a geriatric hospital which had long-term care units. The subjects were 233 consecutive patients who were admitted to K Hospital in the time period April 1994 to March 1996. The isolation rate of MRSA and of Pseudomonas aeruginosa was 10.3% and 8.2% respectively. The proportions of the patients with severely to moderately limited Activities of Daily Living (ADL) (ADL score = 0-1) (P < 0.01), those with fever (P < 0.01), those with CRP positive (P = 0.04) and those with hypoalbuminemia (serum albumin < 3.5 g/dl) (P < 0.01) were higher in the MRSA positive patients than in the negative patients while the proportion of the patients with fever was higher in the Pseudomonas aeruginosa positive patients than in the negative patients (P < 0.02). In the multiple logistic regression analysis, the limitation of ADL (ADL score 0-1 vs 2-3, OR = 1.54, 95% CI = 1.02-2.33) and fever (with vs without, OR = 1.77, 95% CI = 1.18-2.66) remained as risk factors for the isolation of MRSA while only fever (with vs without, OR = 1.67, 95% CI = 1.11-2.53) remained as a risk factor for the isolation of Pseudomonas aeruginosa.

Comparative features of double-contrast barium studies in patients with isosporiasis and strongyloidiasis

OBJECTIVE

To compare the gastrointestinal features of isosporiasis and strongyloidiasis.

METHODS

Two patients with isosporiasis and three patients with strongyloidiasis were assessed by double-contrast radiography of the duodenum and small intestine, with reference to histology of the duodenal biopsy specimens.

RESULTS

Both conditions affected the duodenum and the proximal jejunum, and showed similar radiographic changes as the diseases progressed. Thus, three patients with diarrhoea lasting 1 year or less showed only minimal or irregularly thickened mucosal folds, which seemed to result from mucosal inflammation. Two patients with long-standing disease periods (17 years and 30 years) presented a markedly granular mucosal appearance with effacement of the folds on radiography. These chronological differences in the radiographic features seemed to reflect the degree of villous atrophy.

CONCLUSION

Isosporiasis has similar radiographic features of strongyloidiasis.

Synthesis of creatol, a hydroxyl radical adduct of creatinine and its increase by puromycin aminonucleoside in isolated rat hepatocytes

Creatol is a hydroxyl radical adduct of creatinine and the precursor of methylguanidine (MG), a uremic toxin. We investigate the synthesis of creatol and MG from creatinine and the effect of substances that affect the hydroxyl radical in isolated rat hepatocytes. In the presence of increasing concentrations of creatinine, rising level of creatol were found after 2 h incubation in Krebs-Henseleit bicarbonate buffer. However, further increase of creatol was not observed after 4 and 6h incubations. On the other hand, MG after 2 h incubation achieved a level of about 50% that of creatol and increased depending on both the creatinine concentration and the incubation period. DMSO, a hydroxyl radical scavenger decreased the generation of creatol and MG by about 50% at 2.5 mM and the inhibition depended on DMSO concentration. Puromycin amino-nucleoside (PAN) increased both by about 170%. These findings demonstrated that hepatocytes synthesize creatol prior to MG and are inhibited by a hydroxyl] radical scavenger. They also show that PAN increased hydroxyl radical generation in tissue cells.

Early gastric cancer in the remnant stomach

BACKGROUND/AIMS

Early gastric cancer in the remnant stomach is rare. Periodical endoscopic examinations are mandatory for patients with partial gastrectomy for a good prognosis. Our goal is to improve the surgical management of gastric cancer in the remnant stomach. We have retrospectively investigated a total of 15 rare cases of early gastric cancer after partial gastrectomy.

METHODOLOGY

From 1976 to 1994, a total of 2,102 cases of gastric cancer were resected in our Department. Among these resected cases, 845 cases were histologically diagnosed as having early gastric cancer of the stomach. Of these, 15 patients had previously undergone a partial gastric resection. The time interval between the initial partial gastrectomy and the second resection of the remnant stomach, was more than 10 years for 8 patients (Group 1) and less than 10 years for 7 patients (Group 2). Here we investigate these rare cases of remnant early gastric cancer.

RESULTS

The incidence of early gastric cancer in the remnant stomach was 1.8% (15/845). The cancer location in the remnant stomach was around the stoma and suture line in 75% of Group 1 and in 28.6% of Group 2. The incidence rate of mucosal cancer (m-cancer) was 87.5% for Group 1, and 14.3% for Group 2. Total gastrectomy was selected for 37.5% of Group 1, and for 100% of Group 2. No lymph node metastasis was discovered in both groups. The postoperative mortality was zero in both groups. One patient from Group 2, later died of liver metastasis 2 years after the second total gastrectomy, while the other 9 patients continued to live for more than 5 years with no gastric cancer recurrence to date.

CONCLUSIONS

The outcome for patients with gastric cancer in the remnant stomach is generally considered poor. However, the outcome of early gastric cancer in the remnant stomach was good without major postoperative complications. Therefore, to improve surgical management of remnant-stump gastric cancer, early diagnosis is most important, using periodic endoscopic follow-up examinations, especially around the stoma. When mucosal cancer around the stoma is diagnosed, subtotal gastrectomy can be selected even in gastrectomized patient for a good prognosis.

Specific transcription factors prognostic for prostate cancer progression

We have previously identified (M. Wang et al., Oncol. Res., in press, 1998) an enhancer element [human tissue inhibitor of metalloproteinase-1 enhancer-1 (HTE)] for the human tissue inhibitor of metalloproteinase-1 promoter that binds a novel zinc finger, cysteine-rich transcription factor (CRTF). In this study, we have used electrophoretic mobility shift assays to examine the relative level of expression of CRTF, jun/fos, and IFN-gamma responsive signal transducer activators of transcription (STATs) that bind specific HTE, activator protein, and IFN-gamma (Fcy and interferon regulatory factor) response motifs in tumor lines and human prostate tissue [i.e., normal (n = 3); benign prostatic hyperplasia (BPH; n = 12); high grade prostate intraepithelial neoplasia (PIN; n = 10); and prostate cancer adenocarcinoma (PCA; n = 61) plus seminal vesicle (n = 10) tissues]. The data showed that CRTF was overexpressed in PCA (Gleason's score, 10>8>6>5>4) compared with BPH, PIN, seminal vesicle, and normal tissues. To a much lesser degree, jun/fos and STAT 1 were also elevated in PCA compared to BPH, PIN, and normal tissues. In addition, blinded studies showed that CRTF and jun/fos were present at low levels in organ-confined specimens but at significantly elevated levels (P < 0.001) in samples exhibiting capsular penetration and localized spread, which indicated that CRTF and perhaps jun/fos were markers for cancer progression.

Falls among community-dwelling elderly in Japan

Japanese have a lower incidence of hip fracture than Caucasians despite having lower bone mass. Hip fractures usually occur after a fall, and differing incidence rates of falls might explain the observed differences in hip fracture rates. To explore this hypothesis, we studied falls and related conditions among 1534 (624 men, 910 women) community-dwelling people aged 65 years and over in Japan and compared the prevalence of falls to Japanese-Americans living in Hawaii and to published studies of Caucasians. In Japan, 9% of the men and 19% of the women reported one or more falls during the past year. The prevalence of falls increased with age in both genders and was greater among women compared with men. In logistic regression models, having musculoskeletal disease, physical disability or limited activity increased the risk of falls by two to four times in both genders. Most fallers (92%) reported fear of future falls, and about one third of fallers reported that they went out less often as a result of their falls. Compared with native Japanese, the age-standardized prevalence of falls among Japanese-Americans was similar but about twice as high for Caucasians, which may explain the lower hip fracture risk of Japanese.

Introducing a downsized, open computer system with asynchronous transfer mode in PACS and its effect on image data transfer

To assess the effectiveness of the introduction of a downsized, open computer system and asynchronous transfer mode (ATM) as a network in a medium-sized picture archiving and communication system (PACS), we conducted experiments on image data transmission. The speed of image transfer, including registration in the computers in the new PACS, was four to eleven times faster than that in our first PACS. However, the introduction of ATM did not contribute significantly to the improvement of speed of image transfer because of the use of Ethernet branches between the gateway and display workstation computers. A star architecture without Ethernet branches may be suitable for PACS using an ATM network.

Does myocardial thallium-201 SPECT combined with electron beam computed tomography improve the detectability of coronary artery disease?--comparative study of diagnostic accuracy

OBJECTIVE

The aim of this study is to evaluate the diagnostic accuracy of myocardial 201Tl SPECT combined with EBT for detecting CAD.

METHODS

The study was based on 34 patients with suspected CAD, who had EBT and myocardial 201Tl SPECT. The CAD was diagnosed by the findings of coronary arteriography. Sensitivity, specificity and accuracy of EBT, myocardial 201Tl SPECT and the combined diagnosis on a per vessel basis and a per-patient basis were studied.

RESULTS

The sensitivity for detecting CAD of myocardial 201Tl SPECT, EBT and the combined diagnosis was 85%, 77%, and 62%, respectively. No significant difference in the accuracy of myocardial 201Tl SPECT, EBT and the combined diagnosis was observed on a patient basis and per vessel basis. In the over 70 yr age subgroup, the sensitivity and accuracy of EBT for detecting LAD lesion were significantly superior to those of myocardial 201Tl SPECT. Regardless of age-based subgroups and gender, the combined diagnosis did not contribute to an improvement in diagnostic accuracy.

CONCLUSION

Although the sensitivity of EBT for detecting LAD lesion in patients over 70 yr of age was significantly higher than that of myocardial 201Tl SPECT, in the detectability of CAD, combined use of myocardial 201Tl SPECT and EBT offers no improvement.

Appearance of glucose-induced insulin release in fetal rat beta-cells

Fetal rat pancreatic cells were isolated from pancreatic primordia on days 12-14 of pregnancy and cultured for 48 h in the presence of 5 mmol/l glucose. Insulin accumulation in the medium over the next 24 h was measured. Cultured cells from day 12 fetuses secreted about 1 fmol insulin per pancreas in response to 5 or 15 mmol/l glucose irrespective of whether 1 mmol/l tolbutamide, 400 mumol/l diazoxide, 5 mmol/l theophylline or 10 mmol/l mannoheptulose was present. In contrast, insulin released from day 13 cultured cells increased significantly from 3.0 +/- 0.6 to 6.2 +/- 2.2 fmol per pancreas, when the glucose concentration was raised. Tolbutamide increased, diazoxide and mannoheptulose decreased and theophylline had no effect on insulin release. Even more pronounced effects were found on insulin release from day 14 cultured cells, in which theophylline also increased the release. In addition, insulin release from cells from pregnancy day 14 was 75 +/- 16 amol/min per pancreas when the cells were perifused for 15-20 min in the presence of 5 mmol/l glucose within 3 h of isolation. Increasing the glucose concentration to 15 mmol/l or adding tolbutamide increased, whereas diazoxide decreased, insulin release in the freshly isolated cells. The insulin content of rat pancreata from pregnancy day 13 was 0.06 +/- 0.01 pmol per pancreas and increased approximately 10-fold every second day up to 6.7 +/- 0.9 pmol on day 17 of pregnancy. Between day 17 and 19 the pancreatic insulin content increased about fivefold to 39 +/- 2 pmol. The present data suggest that critical components of the insulin-secretory machinery, including ATP-regulated K+ channels, glucokinase and adenylate cyclase activities, are present in the developing beta-cell earlier than hitherto thought.

[Reproducibility and wave analysis of multifocal electroretinography]

We studied the reproducibility of multifocal electroretinography by repeated measurements in normal subjects. We also analyzed the amplitude and implicit time of the waves. Nine healthy eyes including myopic cases (-4.1 D on average) of 9 normal males, aged 19 to 42 years, were the objects of study. We used a (Visual Evoked Response Imaging System III (VERIS III), by TOMEY Corp.) for multifocal electroretinography. Each eye was examined 4 times on different days. The stimulus elements consisted of 103 hexagons. The net recording time was 4 minutes. We used the coefficient of variation (standard deviation/average) of 4 measurements of response density as index of reproducibility. Poor fixation and blinking were important factors that affected the reproducibility. In all the 9 eyes, reproducibility of multifocal electroretinography, expressed as average of the coefficient of variation of all regions, was 22% on average. In 6 eyes with good fixation and without blinking, the reproducibility was 15% on average. In 6 eyes with good reproducibility, we analyzed three parameters of the focal response waves: all traces, quadrants and rings, as well as the amplitude and latency of the waves. These data served as controls. Our studies showed that the response density correlated closely with the amplitude and not with the latency in normal subjects.

B-cell monoclonality precedes the development of gastric MALT lymphoma in Helicobacter pylori-associated chronic gastritis

Little is known about the temporal changes in Helicobacter pylori density and B-cell clonality during the evolution from chronic gastritis to gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Biopsied specimens from 28 patients with chronic gastritis who developed gastric MALT lymphoma (group A) and from 24 similar patients who did not (group B) during an equivalent follow-up period (mean, 42 months) were retrospectively scored for histological features of MALT lymphoma (0 to 5) and H. pylori density (0 to 3). B-cell clonality was analyzed by polymerase chain reaction (PCR). During the observation period, the H. pylori density in group A decreased significantly in comparison with group B; the mean change in H. pylori density (final minus initial density) per 1000 days was -1.4 for group A and +0.2 for group B (P < 0.005). Monoclonality was detected more frequently in group A (79%) than in group B (21%; P < 0.005), and it preceded the histological evidence of malignant transformation in 64% of those patients who showed monoclonality in group A. These results suggest that H. pylori is thus more closely associated with the precursor or initial phase in the genesis of gastric MALT lymphoma than with the later phase, as its density decreases as the tumor progresses. The detection of B-cell monoclonality by PCR is thus of possible use for predicting the histological genesis of gastric lymphoma.

Biodistribution studies on L-3-[fluorine-18]fluoro-alpha-methyl tyrosine: a potential tumor-detecting agent

Iodine-123-alpha-methyl tyrosine has proven to be a promising SPECT agent for imaging amino acid uptake in tumors. We developed L-[3-(18)F]-alpha-methyl tyrosine (FMT) for PET studies. The aim of this study was to investigate its potential use as a tumor-detecting agent by using tumor-bearing mice.

METHODS

We investigated the biodistribution in normal BALB/C mice and BALB/cA nude mice bearing human rectal cancer cell line (LS180) until 120 min postinjection. FMT tumor uptake at 60 min postinjection in mice with LS180 rectal cancer, RPM11788 B-cell lymphoma and MCF7 mammary cell carcinoma was assessed, and the results were compared with 18F-fluoro-2-deoxy-D-glucose (FDG) tumor uptake. The effect of competitive inhibition of large neutral amino acid transport system using unlabeled L-alanine was also investigated.

RESULTS

The amount of FMT in blood fell to 1.05%ID/20 g at 60 min postinjection, whereas that in the pancreas was 15.2%ID/20 g, resulting in a high pancreas-to-blood ratio of 14.5. In other organs, initial uptake peaked at 5 min postinjection and then declined with time. In LS180 tumor-bearing mice, peak FMT uptake in tumor was observed at 60 min postinjection. Tumor-to-blood and tumor-to-muscle ratios ranged from 1.60 to 2.94 and from 2.79 to 3.25 over the 120-min observation period. Tumor uptake of FMT was clearly reduced by inhibition of the amino acid transport system. In mice with LS180 and MCF7 tumors, FMT tumor uptake at 60 min postinjection was significantly higher than FDG tumor uptake, whereas in RPM11788 lymphoma, uptake of FDG was significantly higher than FMT tumor uptake. Tumor-to-blood ratios of FMT in mice with LS180, RPMI1788 and MCF7 tumor at 60 min postinjection were 1.82, 5.88 and 3.56, respectively.

CONCLUSION

FMT, like other fluorinated amino acids, may become a promising tumor-detecting agent for PET, assuming that efficient methods of radiosynthesis are developed.

[A case of glomerulonephritis with singular high titer of anticardiolipin antibody]

We report here a case of severe membranoproliferative glomerulonephritis with a singular high titer of anticardiolipin antibody (aCL). A 19-year-old Japanese female was admitted to Tsukuba Gakuen Hospital after complaining of general edema for 5 months. She had no past history of thrombosis, thrombocytopenia, or spontaneous abortion. Laboratory findings revealed that she had nephrotic syndrome and moderate renal dysfunction. Immunological test showed a high titer of aCL with a high-normal limit of antinuclear antibody, negativity for anti-beta(2) glycoprotein I antibody and negativity for anti-DNA antibody. In the renal biopsy tissue, most glomeruli showed global sclerosis and the remaining glomeruli revealed membranoproliferative change with crescent formation. Steroid therapy with warfarin and dipyridamole was effective and her renal function improved gradually. This case lacked the typical symptoms of primary antiphospholipid syndrome and did not satisfy the criteria of SLE. In spite of these findings, the singular high titer of aCL with membranoproliferative glomerulonephritis characterized this case.

Calcitonin gene-related peptide affords gastric mucosal protection by activating potassium channel in Wistar rat

BACKGROUND & AIMS

Calcitonin gene-related peptide (CGRP) protects the gastric mucosa against injurious stimuli in various experimental models. The underlying mechanism could be the increase in gastric mucosal blood flow (GMBF). A number of endogenous vasodilators exert their effects through the activation of adenosine triphosphate (ATP)-sensitive potassium (KATP) channels on vascular smooth muscle. The present experiments were performed to elucidate whether CGRP increases GMBF through the activation of KATP channels and whether the channels are involved in the protection by CGRP of gastric mucosa.

METHODS

GMBF was determined by the hydrogen-clearance technique in male Wistar rats. Mucosal lesions were produced by intragastric superfusion with 0.15N HCland 15% ethanol for 40 minutes. Effects of an agonist (Y-26763, intra-arterially) and an inhibitor (glibenclamide, intravenously) of KATP channels were tested.

RESULTS

Y-26763 increased GMBF, which was abolished by glibenclamide, and a CGRP-induced increase in GMBF was attenuated by glibenclamide. Macroscopic and microscopic lesions were exacerbated by human CGRP-(8-37) (a CGRP-1 receptor antagonist; intra-arterially) and glibenclamide but were ameliorated by exogenous CGRP (intra-arterially).

CONCLUSIONS

CGRP protects the gastric mucosa against ulcerogenic stimuli, at least in part, through the activation of KATP channels in rats.

Seroprevalence of Helicobacter pylori infection in Nepal: low prevalence in an isolated rural village

OBJECTIVE

To determine the seroprevalence of Helicobacter pylori infection in Nepal.

DESIGN

H. pylori infection was identified using a specific and sensitive enzyme-linked immunosorbent assay for anti-H. pylori immunoglobulin G.

STUDY POPULATION

Serum samples were collected from 1142 inhabitants (age range 4-93 years) from two villages: Kotyang, a rural isolated village (250 men, 210 women) and Bhadrakali, a suburban village of Kathmandu (334 men, 348 women).

RESULTS

The overall prevalence of H. pylori infection was 56.8%, while significantly higher prevalence was found in the suburban village (Bhadrakali; 67.2%) than in the rural village (Kotyang; 41.5%). This difference was generally reflected by the infection rate in the 10-14-year-old age-group (Bhadrakali, 60% compared with Kotyang, 22.2%). The prevalence of infection significantly increased with age, while no significant difference was found in the prevalence of infection by gender. There was no difference in H. pylori positivity between individuals with and without upper abdominal symptoms in both villages.

CONCLUSION

There was a significant regional difference in the seroprevalence of H. pylori within Nepal, which showed lower prevalence in an isolated rural village. This difference was mainly caused by the different acquisition rate in teenagers, thus indicating that the teenage lifestyle of this particular environment seemed to be the major determinant in the acquisition of H. pylori infection in the population.

Diffuse cystic malformation and neoplasia-associated cystic formation in the stomach. Endosonographic features and diagnosis of tumor depth

We have evaluated the endoscopic ultrasonography (EUS) features of cystic malformation of the stomach and the depth of associated neoplasia. We included 15 patients with multiple cystic components identified on EUS: 6 patients with multiple cysts restricted focally to gastric neoplasia and 9 patients with diffusely distributed cysts. We categorized the former findings as focal cystic malformation (FCM), and the latter as diffuse cystic malformation (DCM) of the stomach and reviewed the endosonographic features. Both FCM and DCM tended to show male preponderance and develop in older patients. Cystic changes in FCM extended from the neoplastic lesion to the submucosa regardless of the location in the stomach. Diffuse cystic malformation was located predominantly in the gastric body and mainly was shown as the thickened submucosa and/or deep mucosa with multiple cystic components. The boundary between the mucosal layer or the tumor echo and the submucosal layer was indistinct in eight patients, which led to a lower accuracy in EUS diagnosis of tumor depth. Diffuse cystic malformation has characteristic EUS features and occasionally is accompanied by gastric neoplasia. Endoscopic ultrasonography is inaccurate in determining tumor depth when multiple submucosal cysts are present.

Cloning of mDEAH9, a putative RNA helicase and mammalian homologue of Saccharomyces cerevisiae splicing factor Prp43

Yeast splicing factor Prp43, a DEAH box protein of the putative RNA helicase/RNA-dependent NTPase family, is a splicing factor that functions late in the pre-mRNA splicing pathway to facilitate spliceosome disassembly. In this paper we report cDNA cloning and characterization of mDEAH9, an apparent mammalian homologue of Prp43. Amino acid sequence comparison revealed that the two proteins are approximately 65% identical over a 500-aa region spanning the central helicase domain and the C-terminal region. Expression of mDEAH9 in S. cerevisiae bearing a temperature-sensitive mutation in prp43 was sufficient to restore growth at the nonpermissive temperature. This functional complementation was specific, as mouse mDEAH9 failed to complement mutations in related splicing factor genes prp16 or prp22. Finally, double label immunofluorescence experiments performed with mammalian cells revealed colocalization of mDEAH9 and splicing factor SC35 in punctate nuclear speckles. Thus, the hypothesis that mDEAH9 represents the mammalian homologue of yeast Prp43 is supported by its high sequence homology, functional complementation, and colocalization with a known splicing factor in the nucleus. Our results provide additional support for the hypothesis that the spliceosomal machinery that mediates regulated, dynamic changes in conformation of pre-mRNA and snRNP RNAs has been highly conserved through evolution.

Early gastric cancer and lymph node metastasis

A total of 1,845 cases of gastric cancer have been resected in our hospital during the past 18 years. Of these, 764 cases (41.5%) were early gastric cancer. The rate of lymph node metastasis was 2% in early mucosal cancer and 19.4% in early submucosal cancer (p < 0.001). In the cases of early mucosal cancer, the rate of lymph node metastasis was 0.9% for the elevated type and 2.4% for the depressed type. In the cases of early submucosal cancer, the rate of lymph node metastasis was 25.3% for the elevated type and 17.3% for the depressed type. In the mucosal cancers the rate of lymph node metastasis was high in the 0-IIc and IIc + III macroscopic type, and in the poorly differentiated microscopic type. In the submucosal cancers the rate of lymph node metastasis was 40% in mucinous adenocarcinoma and 33% in papillary adenocarcinoma. There was no lymph node metastasis in any case of early gastric cancer smaller than 1 cm surface diameter.

Ménétrièr's disease associated with Helicobacter pylori infection: resolution of enlarged gastric folds and hypoproteinemia after antibacterial treatment

We herein report a case of a 46-yr-old female with Ménétrièr's disease associated with Helicobacter pylori (H. pylori) infection, in whom the appearance of enlarged gastric folds and hypoproteinemia were both successfully treated by antibacterial treatment. The patient had been treated with famotidine for 3 yr under a diagnosis of Ménétrièr's disease, which caused an increase in her serum protein concentration to a level at which she suffered no clinical problems; however, the concentration never reached a normal range, and the presence of enlarged gastric folds also remained unchanged. Because H. pylori colonization was detected in the stomach and was also retrospectively recognized in the initial histologic specimens, antibacterial treatment with omeprazole, clarithromycin, and metronidazole was thus attempted. As a result of the successful eradication of H. pylori, the enlarged gastric folds returned to normal and the serum protein concentration thus increased to a normal level after the treatment. The etiology of Ménétrièr's disease remains unknown; however, the above findings suggest that H. pylori infection may in some cases cause Ménétrièr's disease and should therefore be carefully treated in any patient with this condition.

Antitumor activity of a novel quinoline derivative, TAS-103, with inhibitory effects on topoisomerases I and II

A novel quinoline derivative, TAS-103 (6-[[2-(dimethylamino)ethyl]amino]-3-hydroxy-7H-indeno[2,1-c]quinolin -7-one dihydrochloride), was developed as an anticancer agent targeting topoisomerases (topo) I and II, with marked efficacy in solid tumors. TAS-103 inhibited topo I and II (IC50: 2 microM, 6.5 microM) at a concentration similar to or lower than those of previous agents, and had a strong cytotoxic effect on P388 and KB cells (IC50: 0.0011 microM, 0.0096 microM). TAS-103 stabilized topo I and II-DNA cleavable complexes in KB cells, generating a similar amount of topo II-DNA complex to that induced by etoposide (VP-16) but a smaller amount of topo I-DNA complex than that produced by camptothecin (CPT). In the in vivo study, intermittent i.v. administration was markedly effective against s.c.-implanted murine tumors. Furthermore, TAS-103 had marked efficacy against various lung metastatic tumors, and a broad antitumor spectrum in human tumor xenografts (derived from lung, colon, stomach, breast, and pancreatic cancer). The efficacy of TAS-103 was generally greater than that of irinotecan (CPT-11), VP-16, or cis-diamminedichloroplatinum (CDDP).

Juvenile polyposis of the stomach: clinicopathological features and its malignant potential

AIMS

To clarify a clinical entity of juvenile polyposis of the stomach compared with generalised juvenile gastrointestinal polyposis.

METHODS

The clinicopathological features of juvenile polyposis dominantly involving the stomach at initial presentation were reviewed in 12 patients (three new patients and nine from the literature). These were compared with 29 cases of generalised juvenile gastrointestinal polyposis.

RESULTS

There were three men and nine women with juvenile polyposis of the stomach, aged 10-63 years. Hypoproteinaemia was present in nine patients, anaemia in seven, and a family history of intestinal polyposis in seven. No patient presented with a congenital abnormality. During the observation period, two patients developed colonic juvenile polyps. Gastric polyps invariably affected the antrum and extended to the fundus, eventually becoming more numerous, larger, and more pedunculated. Ten patients required gastrectomy for associated malignancy or uncontrolled protein losing gastropathy. Histological examinations of the resected specimens demonstrated neoplastic tissue arising from juvenile polyps in four of the 12 patients. Atypism in these mixed polyps varied from adenoma to well or moderately differentiated adenocarcinoma.

CONCLUSIONS

Juvenile polyposis of the stomach has malignant potential, and may be a separate entity from generalised juvenile gastrointestinal polyposis.

Photochemically induced colonic ischaemic lesions: a new model of ischaemic colitis in rats

BACKGROUND

Recent clinical studies suggest that ischaemic colitis is caused by a microcirculatory disturbance that involves thrombosis of the colon.

AIM

To establish a new model of photochemically induced ischaemic colitis in rats.

METHODS

Thirty male Wistar rats were anaesthetised with amobarbital, the femoral veins were cannulated and laparotomies were performed. The serosal surface of the proximal colon was irradiated by using a krypton laser (wavelength 568 nm, 20 mW) for four minutes. An intravenous infusion of a photosensitising dye, rose bengal (20 mg/kg body weight), was administered over 90 seconds, beginning at the start of irradiation. Rats were killed immediately (n = 4), 12 hours (n = 2), 24 hours (n = 10), three days (n = 4), seven days (n = 4), 14 days (n = 2), or 28 days (n = 2) after irradiation. Two control rats received laser irradiation without dye infusion. Specimens of the irradiated sites were examined by using histopathology.

RESULTS

Localised ulcers of the colon were present in rats killed at 12 hours, 24 hours, three days, and seven days after irradiation. Microscopy findings were consistent with the features of human ischaemic colitis. Reproducible ulcerative lesions were produced by photothrombosis of microvessels in the colon.

CONCLUSION

This model may be useful for further investigation of the pathophysiology of ischaemic colitis.

Methicillin-resistant Staphylococcus aureus (MRSA) isolation from pharyngeal swab cultures of Japanese elderly at admission to a geriatric hospital

The isolation rate of the methicillin-resistant Staphylococcus aureus(MRSA) from pharyngeal swab cultures in Japanese elderly was studied at admission to a geriatric hospital. The subjects were 233 consecutive patients admitted to Kitakyushu Tsuyazaki Hospital from April 1994 to March 1996. The isolation rate of MRSA was 3.0% in the patients admitted from their own homes, 9.7% in those transferred from nursing homes and 14.0% in those transferred from other hospitals. The patients from their own homes were younger than those from nursing homes, the latter being older than those transferring from other hospitals. The patients from their own homes had better activities of daily living(ADL), higher levels of hemoglobin and serum albumin than those from nursing homes or other hospitals. The white blood cell counts, and the proportion of patients with positive c-reactive protein or with fever did not differ among the three groups. Multiple logistic regression analysis revealed that fever and ADL disability were independent risk factors for the isolation of MRSA, and hypoalbuminemia was a risk factor for MRSA isolation in the model using serum albumin instead of ADL score. These results suggest that the lower isolation rate MRSA among patients from their own homes may be partly due to better ADL and nutritional status compared with those from nursing homes or other hospitals.

[Analysis of choroidal blood flow by laser speckle flowgraphy]

We applied real-time laser speckle flowgraphy (RLSFG) to quantitate the choroidal circulation. RLSFG was developed utilizing the laser speckle phenomenon. A diode laser, 830 nm in wavelength, serves as the light source. The quantitative index of blood flow velocity is represented as normalized blur (NB), or square blur rate (SBR). This method was applied to the posterior fundus of monkey and human eyes. While one measurement covers a fundus area of 1 mm x 1 mm, it is possible to measure a wider fundus area by montage. The wide color maps showed the architecture of choroidal vessels. It was possible to measure the choroidal blood flow in areas free of major retinal vessels. Application of the method to 3 eyes of retinal artery occlusion and 4 eyes of geographic choroiditis showed that the obtained SBR values in normal fundus is derived 25% from the retinal and 75% from the choroidal circulation. The findings show the potential value of RLSFG in quantitating the choroidal blood flow in situ.

Favorable effect of hemodialysis on decreased serum antioxidant activity in hemodialysis patients demonstrated by electron spin resonance

There is considerable evidence that uremic patients are in a highly peroxidative state. The purpose of this study was to investigate the serum antioxidant activity that may regulate, or represent, the redox state in vivo. Serum from pre- and posthemodialysis patients and from healthy control subjects was added to a system generating the hydroxyl radical, and then the signal intensities of reactive oxygen species were measured by electron spin resonance and spin-trapping technique. The electron spin resonance signals of the reaction mixture containing prehemodialysis sera were significantly stronger than those of the reaction mixture containing healthy sera (P < 0.001, n = 19), and there was no significant difference in the signals between the reaction mixture containing posthemodialysis and healthy sera. These findings demonstrated that serum antioxidant activity in hemodialysis patients is significantly decreased, and this pathological condition is improved by hemodialysis treatment.

[The significance of p21 expression in gastric cancer]

We examined the expression of p53, p21, cyclin D1, E, and PCNA in 75 cases of gastric cancer by immunohistochemical study and the expression of p21 RNA in cases by in situ hybridization. The rate of stage III, IV cases of p53(+) p21(-) group was significantly higher than that of any other groups. The apportinately 3-year survival rate of p53(+) p21(-) group was significantly lower than either that of p21(+) p53(-) or p53(-) p21(-) group. The 3-year survival rates of positive cases were significantly lower than those of negative cases on both cyclin D1 and E. The positive rate of cyclin E of the p53(-) p21(+) group was significantly lower than that of the p53(+) p21(-) group. The average PCNA Labeling. Index (LI) of the p53(+) p21(-) group was significantly higher than that of the p53(-) p21(+) group. The 3-year survival rate of cases with expression of p21 RNA was higher than that of cases without p21 RNA. Average PCNA L1 of cases with expression of mutant-type p53 was high and the number of poor prognostic cases in cases with expression of mutant-type p53 was large. In contrast, the average PCNA LI of cases with expression of p21 was low and the number of good prognostic cases with expression of p21 was large. These results suggest that p21 suppresses synthesis of DNA via cyclin E and PCNA.

Desmoid tumors in familial adenomatous polyposis/Gardner's syndrome

To clarify the clinical risk of desmoid tumors developing in familial adenomatous polyposis, we reviewed the cases of 49 Japanese patients diagnosed with familial adenomatous polyposis at our institute. In six patients who manifested desmoid tumors at a mean age of 31 years, we reviewed the clinical features and compared various phenotypic manifestations with those in the 43 patients without desmoid tumors. During the observation periods (mean, 6.5 years), two of six patients with desmoid tumors died because of the tumors, which measured > 10 cm in diameter at the initial diagnosis, whereas the remaining four patients with desmoid tumors < 5 cm did not experience complications. The patients with desmoid tumors tended to be women (5 of 6 vs. 17 of 43; p = 0.05) and more frequently had gastric fundic gland polyposis (5 of 6 vs. 17 of 43; p = 0.05) than did the patients without desmoid tumors. There were no apparent differences in other clinical manifestations, including the incidences of colonic polyposis, gastroduodenal adenomas, and extraintestinal tumors. Desmoid tumors can be serious complication in patients with familial adenomatous polyposis. There may be some association in the genesis of desmoid tumors and gastric fundic gland polyposis.

Serum n3 polyunsaturated fatty acids are depleted in Crohn's disease

To determine fatty acid patterns in Crohn's disease, we measured various serum fatty acids by gas chromatography in 20 patients with the disease and compared them with those in 18 healthy controls. All the patients had been free from any nutritional supplementation during preceding six months or had no history of intestinal resection. Eight of the patients were affected in the small bowel only, three in the large bowel only, and the remaining nine in both the small and large bowel. Both serum concentrations and percentages of C20:4n6, C20:5n3, C22:0, C22:6n3, total n3 polyunsaturated fatty acids, and total polyunsaturated fatty acids were lower in the patients than in the controls. Both essential fatty acids (C18:2n6, C18:3n3) and C20:3n9 levels were not different between the two groups. Among nine fatty acids that correlated with the Crohn's disease activity index, C20:5n3 and total n3 polyunsaturated fatty acids showed the most significant negative correlations. These findings suggest that essential fatty acid deficiency rarely occurs in Crohn's disease and also that n3 polyunsaturated fatty acids may be relevant to the activity of the disease.

Age-related changes of serum progastrin-releasing peptide levels during childhood

Gastrin-releasing peptide (GRP) has attracted much attention in recent years because it has become recognized as a significant tissue-specific growth factor. To investigate the physiological significance of this peptide in growing children, the time course of serum ProGRP(31-98) level, a precursor hormone of GRP, in children was assessed. A total of 118 serum samples including cord blood was examined with informed consent by using a specific enzyme-linked immunosorbent assay (ELISA) system to measure serum ProGRP(31-98). The serum ProGRP(31-98) level was highest in cord blood and neonatal samples, rapidly declined by 1 year of age and then gradually declined to the adult level by 5 years of age. This time-dependent change of serum ProGRP(31-98) level suggests the importance of GRP as a physiological growth factor in fetal and neonatal tissues.