Down-regulation of single immunoglobulin interleukin-1R-related molecule (SIGIRR)/TIR8 expression in intestinal epithelial cells during inflammation

Single immunoglobulin (Ig) interleukin-1R-related molecule (SIGIRR) is an Ig-like membrane protein critical for negative regulation of Toll-like receptor (TLR)-4-mediated signalling. We investigated SIGIRR expression and its regulation mechanism in intestinal epithelial cells (IECs) during inflammation. Endoscopic biopsy specimens were obtained from active and inactive colonic mucosa of ulcerative colitis (UC) patients, then SIGIRR expression was examined using real-time polymerase chain reaction (PCR) and immunohistochemistry (IH). Mice experimental colitis models were established by administrations of sulphonic acid (TNBS) and dextran sodium sulphate (DSS), and epithelial expression of SIGIRR was examined using real-time PCR, IH and flow cytometry. The effects of lipopolysaccharide (LPS) and tumour necrosis factor (TNF)-α on SIGIRR expression were evaluated in vitro using cultured IECs. To elucidate SIGIRR expression regulation in IECs, binding ability of the transcription factor SP1 at the responsive element of the SIGIRR promoter was examined using gel-shift and chromatin immunoprecipitation (ChIP) assays. In human colonic samples, SIGIRR was expressed mainly in IECs at levels significantly higher in inactive compared to active mucosa. In the mice, SIGIRR colonic expression decreased rapidly after colitis development and returned gradually to basal levels. Experimental colitis-mediated down-regulation of SIGIRR in IECs was also confirmed by IH and flow cytometry results. Further, inflammatory conditions induced by TLR ligands and TNF-α caused significant down-regulation of SIGIRR expression in IECs, which was dependent upon decreased SP1 binding at the responsive element of the SIGIRR promoter. We found that SIGIRR is expressed in IECs and serves as a negative regulator to maintain gut innate immunity, which is down-regulated during inflammation by inhibition of an SP1-mediated pathway.

Oolong tea is useful for lens cleansing in transnasal small-caliber esophagogastroduodenoscopy

BACKGROUND AND STUDY AIMS

Unsedated transnasal small-caliber esophagogastroduodenoscopy (EGD) has been used to examine the upper gastrointestinal tract with proven feasibility and tolerability. However, a limitation of transnasal EGD is the poor lens-cleansing function of the scope due to the small-caliber water-jet nozzle. Therefore, this trial was designed to evaluate the cleansing effect of oolong tea for transnasal small-caliber EGD.

PATIENTS AND METHODS

Oolong tea (O), barley tea (B), and distilled water (W) were prepared as washing solutions for endoscopic lenses. Study I: after the lenses were soiled by lard oil, they were washed with one of the three washing solutions, and the image quality of photographs was judged. Study II: 982 patients who were due to undergo transnasal EGD were enrolled and randomly assigned to the O-, B-, or W-groups. The level of lens cleansing, the overall time required for endoscopy, and the volume of washing solution used were measured.

RESULTS

Study I: the image quality of photographs taken with lenses washed with oolong tea was significantly superior to that associated with other solutions. Study II: the level of lens cleansing in the O-group was significantly superior to that of the B- and W-groups ( P < 0.001). The volume of solution used for lens cleansing in the O-group was significantly smaller than that in the W-group ( P < 0.05). Endoscopic examination times in the O-group were shorter than those in the B- and W-groups ( P < 0.05).

CONCLUSIONS

In transnasal small-caliber EGD, oolong tea instead of water as a washing solution for endoscopic lens cleansing is useful to maintain good visibility.

A20 is an early responding negative regulator of Toll-like receptor 5 signalling in intestinal epithelial cells during inflammation

Several negative regulatory mechanisms control Toll-like receptor (TLR)-mediated inflammatory responses and restore immune system balance, including the zinc-finger protein A20, a negative regulator of TLR signalling that inhibits nuclear factor kappa B (NF-kappaB) activity. In the present study, we investigated TLR-5-mediated A20 expression and its role in intestinal epithelial cells (IECs) during inflammation. HCT-15 and HT-29 cells were stimulated with flagellin, then the expressions of A20, interleukin-1 receptor-associated kinase (IRAK-M) and Tollip were evaluated using RNase protection assay. Furthermore, experimental colitis was induced in tlr4-deficient CH3/HeJ mice by administration of dextran sodium sulphate (DSS), then flagellin was injected anally, and the colonic expression of A20 was examined by real-time polymerase chain reaction (PCR) and immunohistochemistry. To confirm flagellin-induced expression of A20, we employed an organ culture system. The role of A20 in flagellin-induced tolerance induction was evaluated in vitro, using a gene knock-down method targeting A20. A20 expression increased rapidly and peaked at 1 h after flagellin stimulation in cultured IECs, then declined gradually to the basal level. In vivo, anal injection of flagellin induced epithelial expression of A20 in injured colonic tissue, whereas flagellin did not cause a significant increase in A20 expression in non-injured normal tissue, which was also confirmed in vitro using the organ culture system. Gene knock-down using A20 siRNA did not influence tolerance induced by restimulation with flagellin. A20 is an early response negative regulator of TLR-5 signalling in IECs that functions during intestinal inflammation. Our results provide new insights into the negative feedback regulation of TLR-5 signalling that maintains the innate immune system in the gut.

[Hypersensitity pneumonitis in a greenhouse rose grower]

A 54-year-old woman presented with chronic cough. She had been engaged in growing roses in plastic greenhouses. Chest CT scan showed bilateral diffuse ground-glass attenuation. Bronchoalveolar lavage fluid demonstrated the increase of total cell counts with predominant lymphocyte cells, and transbronchial lung biopsy specimen revealed lymphocyte alveolitis with granuloma. Precipitating antibody against the extract of the Penicillium species obtained in the greenhouses was detected by the double immunodiffusion test, which led to a diagnosis of hypersensitivity pneumonitis caused by Penicillium species. This case suggests the risk of hypersensitivity pneumonitis caused by fungi in closed spaces with high temperature and humidity such as greenhouses.

Immediate effects of a rucksack type orthosis on the elderly with decreased lumbar lordosis during standing and walking

The spinal orthosis, the so-called rucksack type orthosis (RO), has been used to relieve low back pain and fatigue during prolonged standing and walking for the elderly with spinal deformities. However, little is known about the RO's kinematical effects. Twenty-three elderly (78.9 +/- 6.9 years old) participated in experiment 1, and 13 elderly (78.4 +/- 7.9 years old) in experiment 2. They had decreased lumbar lordosis or lumbar kyphosis. In experiment 1, using the "Spinal Mouse", which can measure spinal curvature, the effects of the RO on posture during standing were investigated. In experiment 2, using electromyography, the effects of the RO on muscle activity during standing and walking were clarified. Lumbar curvature and the trunk angle of inclination during standing improved significantly when the RO was used. Back extensor muscle activities (T9, L3, and L5) during standing and walking decreased significantly when the RO was used. There were no significant differences in the activities of the upper trapezius and vastus lateralis during standing and walking. The present study suggests that the elderly with lumbar deformities might be able to stand and walk more efficiently with the RO. The RO could prove to be valuable in preservation therapy for the elderly with decreased lumbar lordosis or lumbar kyphosis.

Pre-exposure to infectious hypodermal and haematopoietic necrosis virus or to inactivated white spot syndrome virus (WSSV) confers protection against WSSV in Penaeus vannamei (Boone) post-larvae

Larvae and post-larvae of Penaeus vannamei (Boone) were submitted to primary challenge with infectious hypodermal and haematopoietic necrosis virus (IHHNV) or formalin-inactivated white spot syndrome virus (WSSV). Survival rate and viral load were evaluated after secondary per os challenge with WSSV at post-larval stage 45 (PL45). Only shrimp treated with inactivated WSSV at PL35 or with IHHNV infection at nauplius 5, zoea 1 and PL22 were alive (4.7% and 4%, respectively) at 10 days post-infection (p.i.). Moreover, at 9 days p.i. there was 100% mortality in all remaining treatments, while there was 94% mortality in shrimp treated with inactivated WSSV at PL35 and 95% mortality in shrimp previously treated with IHHNV at N5, Z1 and PL22. Based on viral genome copy quantification by real-time PCR, surviving shrimp previously challenged with IHHNV at PL22 contained the lowest load of WSSV (0-1x10(3) copies microg-1 of DNA). In addition, surviving shrimp previously exposed to inactivated WSSV at PL35 also contained few WSSV (0-2x10(3) copies microg-1 of DNA). Consequently, pre-exposure to either IHHNV or inactivated WSSV resulted in slower WSSV replication and delayed mortality. This evidence suggests a protective role of IHHNV as an interfering virus, while protection obtained by inactivated WSSV might result from non-specific antiviral immune response.

Interobserver agreement on classifying endoscopic diagnoses of nonerosive esophagitis

BACKGROUND AND STUDY AIMS

The majority of patients with gastroesophageal reflux disease in Japan have low-grade esophagitis, including minimal changes. A modified Los Angeles classification of esophagitis, consisting of erosive esophagitis (grades A - D) and nonerosive esophagitis (grades M and N) has been proposed and is in clinical use in Japan. However, it is unclear whether nonerosive esophagitis with only undemarcated mucosal discoloration (grade M) is clinically significant, since interobserver variations in classification have not been investigated. The aim of the present study was therefore to evaluate interobserver variance and diagnostic agreement in the diagnosis of nonerosive esophagitis (grades M and N).

MATERIALS AND METHODS

A total of 84 endoscopists were enrolled to assess the grade of esophagitis in 30 patients by viewing endoscopic images of the gastroesophageal junction. The images were projected onto a screen, and all of the endoscopists reviewed them concurrently. The diagnosis was selected from the following three categories in the modified Los Angeles classification: grades N, M, or A. The endoscopists were grouped according to their experience, whether they had a board license, and whether they had received specialist training in esophagitis. The kappa coefficient of reliability was calculated.

RESULTS

The kappa coefficient of reliability for all the endoscopists in the diagnosis of cases of grade M and N nonerosive esophagitis was unacceptably low at 0.22 (95 % CI, 0.21 - 0.24). Endoscopists with a board license and those who had completed a special esophagitis diagnostic course had slightly higher kappa values (0.26; 95 % CI, 0.23 - 0.30 and 0.29; 95 % CI, 0.26 - 0.32), respectively.

CONCLUSIONS

Interobserver agreement on the endoscopic diagnosis of nonerosive esophagitis (grades M and N) is too low to be of clinical value.

Effective detection of the epidermal growth factor receptor mutation in pathologic specimens of non-small cell lung cancer patients by a rapid and sensitive detection system, the peptide nucleic acid-locked nucleic acid PCR Clamp

20113

Background: EGFR mutations link to the responsiveness to gefitinib, so it is important to get result of EGFR mutations more rapidly and sensitively. Methods: We screened 14 trans-bronchial lung biopsy (TBLB) specimens of non-small cell lung cancer (NSCLC) patients; 10 patients responded to gefitinib and 4 patients did not respond to gefitinib. We examined exons 18 through 21 (the area of the EGFR gene coding for the tyrosine kinase domain) both by the PNA-LNA PCR clamp method and the conventional sequence method. Results: We found five different mutations in 9 patients of 10 who responded to gefitinib by the PNA-LNA PCR clamp method, but only in 7 patients by the conventional sequence method. Detected mutations were the point mutation of exon 18(719S) and exon 21(858R), deletions of exon 19 (E746-A750del (nt2235–2249), E746-A750del (nt2236–2250), L747-E749del A750P). All 4 patients who did not respond to gefitinib were not detected any EGFR mutations either by the PNA-LNA PCR clamp method or by the conventional sequence method. We could get result for 2 days by the PNA-LNA PCR method, but by 7 days by the conventional sequence method routinely. Conclusions: The PNA-LNA PCR clamp method is more sensitive and rapid than the conventional sequence method. The detected EGFR mutations have good relation to gefitinib response.

No significant financial relationships to disclose.

Evaluation of modified crystal violet chromoendoscopy procedure using new mucosal pit pattern classification for detection of Barrett's dysplastic lesions

BACKGROUND

Pit pattern diagnosis is important for endoscopic detection of dysplastic Barrett's lesions, though using magnification endoscopy can be difficult and laborious. We investigated the usefulness of a modified crystal violet chromoendoscopy procedure and utilised a new pit pattern classification for diagnosis of dysplastic Barrett's lesions.

METHODS

A total of 1,030 patients suspected of having a columnar lined oesophagus were examined, of whom 816 demonstrated a crystal violet-stained columnar lined oesophagus. The early group of patients underwent 0.05% crystal violet chromoendoscopy, while the later group was examined using 0.03% crystal violet with 3.0% acetate. A targeted biopsy of the columnar lined oesophagus was performed using crystal violet staining after making a diagnosis of closed or open type pit pattern with a newly proposed system of classification. The relationship between type of pit pattern and histologically identified dysplastic Barrett's lesions was evaluated.

RESULTS

Dysplastic Barrett's lesions were identified in biopsy samples with an open type pit pattern with a sensitivity of 96.0%. Further, Barrett's mucosa with the intestinal predominant mucin phenotype was closely associated with the open type pit pattern (sensitivity 81.9%, specificity 95.6%).

CONCLUSIONS

The new pit pattern classification for diagnosis of Barrett's mucosa was found to be useful for identification of cases with dysplastic lesions and possible malignant potential using a crystal violet chromoendoscopic procedure.

[The history and library the Goda family of medical doctors]

The Goda family discussed in this paper is a family lineage that served as the official physicians to the Sakakibara family that ruled Takada han in Echigo province from the middle of the Edo period. Last year old medical materials and writings that had been transmitted by the family were transferred to the Oriental Medicine Research Center of the Kitasato Institute. The authors have had the opportunity to study the family genealogy and collate these archives. The Goda family has continued through eight generations. These are, respectively- (1) the founder Heizo; (2) Chuzo; (3) Shojun; (4) Yoan; (5) Yoshinobu; (6) Hitoshi; (7) Hiroshi; and (8) the present head, Takashi. We have identified two lines of physicians in collateral families (from Susumu and Akira, both sons of Yoshinobu). The archive as received is comprised of 138 separate items from a total of 450 volumes. Of these, medical works constitute 102 items in 283 volumes. The library provides valuable material which sheds light on the standard of medicine in the Takada area of Echigo from the late Edo through the Meiji periods.

Role of cellulose-binding domain of exocellulase I from white rot basidiomycete Irpex lacteus

The core fragment (designated P-42), devoid of the cellulose-binding domain (CBD) in the C-terminus and prepared from Irpex lacteus exocellulase I (Ex-1), was isolated by limited proteolysis using papain. Both the hydrolytic activity and binding ability of the isolated P-42 toward insoluble cellulose were lower than those of the native Ex-1, whereas Ex-1 and P-42 showed similar hydrolytic activities toward soluble substrates. These results indicate that the CBD of I. lacteus Ex-1 is the important domain which could enhance hydrolytic activity and binding ability of the enzyme toward insoluble cellulose. In addition, the isolated P-42 was different from the native Ex-1 in terms of enzymatic properties such as pH and temperature stabilities. These differences in stability, with regard to pH and temperature, between P-42 and the native Ex-1 are probably due to the O-linked sugar chains existing in the linker region.

Helicobacter pylori infection influences symptomatic response to anti-secretory therapy in patients with GORD--crossover comparative study with famotidine and low-dose lansoprazole

BACKGROUND AND AIM

Helicobacter pylori infection was reported to affect gastric acid secretion. We investigated the heartburn symptoms of patients with gastro-oesophageal reflux disease during sequential treatment with 40 mg of famotidine or 15 mg of lansoprazole to clarify whether H. pylori infection influences symptomatic response to anti-secretory therapy.

SUBJECTS AND METHODS

The subjects were 33 gastro-oesophageal reflux disease patients, who had already been treated with a full dose of H2 receptor antagonist. First, famotidine at 20 mg b.i.d. was administered to the patients for 8 weeks. Second, famotidine was replaced with 15 mg of lansoprazole once in the morning for 8 weeks. Finally, 20 mg of famotidine was administered b.i.d. for 8 weeks instead of lansoprazole. Gastro-oesophageal reflux disease symptoms were assessed using an original visual analogue scale.

RESULTS

The sequential symptomatic responses to famotidine and lansoprazole administration indicated that gastro-oesophageal reflux disease symptoms of patients during low-dose lansoprazole treatment were significantly less than those during famotidine treatment. Remission of symptoms was obtained significantly more often by famotidine therapy in patients with H. pylori infection than in patients without H. pylori infection.

CONCLUSION

Low-dose lansoprazole is more effective than full-dose famotidine for the control of symptoms in patients with gastro-oesophageal reflux disease, and H. pylori infection influences the symptomatic response to H2 receptor antagonists.

Correlation between dietary glycemic index and cardiovascular disease risk factors among Japanese women

OBJECTIVE

To examine the correlation between dietary glycemic index (GI) and cardiovascular disease (CVD) risk factors among subjects who consume white rice as a staple food.

DESIGN

A cross-sectional study was conducted to explore the associations between dietary GI, dietary glycemic load (GL) and dietary intakes, and CVD risk factors. Dietary GI and GL were calculated from a 3-day (including two consecutive weekdays and one holiday) dietary records.

SETTING

A weight-reduction program at a municipal health center in Tokyo, Japan.

SUBJECTS

A total of 32 women aged 52.5+/-7.2 y participated in the weight-reduction program.

RESULT

The GI food list made for the current study calculated for 91% of carbohydrate intakes measured. The mean dietary GI was 64+/-6, and the mean dietary GL was 150+/-37. Individuals in the highest tertile of GI consumed more carbohydrate, mostly from white rice (P<0.001), and less fat (P<0.01). Individuals in all three groups by tertile of GL showed similar tendencies. In the lowest GI tertile, the highest concentration of HDL-cholesterol and lowest concentration of triacylglycerol and immunoreactive insulin were observed (P<0.01). In the lowest GL tertile, the highest concentration of HDL-cholesterol and the lowest concentration of triacylglycerol were observed (P<0.05).

CONCLUSION

Calculated dietary GI and GL were positively associated with CVD risk factors among the Japanese women who consumed white rice as a staple food.

Barrett's oesophagus with predominant intestinal metaplasia correlates with superficial cyclo-oxygenase-2 expression, increased proliferation and reduced apoptosis: changes that are partially reversed by non-steroidal anti-inflammatory drugs usage

BACKGROUND

Cyclo-oxygenase-2 expression has been reported to play an important role in the metaplasia-dysplasia-carcinoma sequence in Barrett's oesophagus. However, the existence of cyclo-oxygenase-2 expressing cells in Barrett's epithelium is still uncertain.

AIM

To identify the cells that express cyclo-oxygenase-2 protein and to investigate the relationship between cyclo-oxygenase-2 expression and mucin-phenotype of Barrett's epithelium.

METHODS

Sections from 466 biopsy samples of Barrett's epithelium from 358 non-medicated patients were immunohistochemically examined for the cyclo-oxygenase-2 expression, mucin-phenotype, cell proliferation and apoptosis.

RESULTS

Cyclo-oxygenase-2 expression was detected in 71.0% of Barrett's epithelium biopsy samples. In Barrett's epithelium with the gastric predominant mucin-phenotype, cyclo-oxygenase-2 expression was mainly found in stromal and deep epithelial cells, whereas in intestinal predominant mucin-phenotype, it was mostly in superficial epithelial cell. A significant elevation of proliferating cell nuclear antigen index and suppression of apoptotic index was observed in Barrett's epithelium with superficial epithelial cyclo-oxygenase-2 expression. Neither such elevation of proliferating cell nuclear antigen index nor the suppression of apoptotic index could be found in chronic non-steroidal anti-inflammatory drugs users.

CONCLUSIONS

Barrett's epithelium with intestinal mucin and superficial epithelial cyclo-oxygenase-2 expression possess a higher proliferation potential, but this risk may be thwarted by non-steroidal anti-inflammatory drugs administration.

Which types of non-bleeding visible vessels in gastric peptic ulcers should be treated by endoscopic hemostasis?

BACKGROUND AND AIMS

Because non-bleeding visible vessels (NBVV) of gastric peptic ulcers have the potential to re-bleed, endoscopic hemostatic treatment may be necessary during the first emergency endoscopy. However, not all NBVV re-bleed, and endoscopic hemostasis sometimes causes fatal side-effects. Therefore, we have evaluated the risk of re-bleeding from various NBVV in gastric peptic ulcers to determine which types should be treated by endoscopy to prevent re-bleeding.

METHODS

A total of 227 NBVV in 202 patients with gastric peptic ulcers that were endoscopically followed without endoscopic hemostatic procedures were classified by the following factors: vessel color, form, location of the NBVV in the ulcer crater, and location of the ulcer in the stomach. The re-bleeding rate was then analyzed for each type of NBVV.

RESULTS

Significantly high rates of re-bleeding were observed in cases with white, protruded and peripheral NBVV. In particular, white NBVV located in the peripheral zone of the ulcer crater were frequent re-bleeding sources. The location of the ulcer in the stomach was not a statistically significant factor in determining re-bleeding rates.

CONCLUSION

We found that white, protruded and peripherally located NBVV in gastric ulcers have a higher chance of re-bleeding if preventive endoscopic hemostatic procedures are not performed.

IL-12 Production Induced by Agaricus blazei Fraction H (ABH) Involves Toll-like Receptor (TLR)

Agaricus blazei Murill is an edible fungus used in traditional medicine, which has various well-documented medicinal properties. In the present study, we investigated the effects of hemicellulase-derived mycelia extract (Agaricus blazei fraction H: ABH) on the immune system. First, we examined the cytokine-inducing activity of ABH on human peripheral mononuclear cells (PBMC). The results indicated that ABH induced expression of IL-12, a cytokine known to be a critical regulator of cellular immune responses. Flow cytometric analysis demonstrated the induction of IL-12 production by the CD14-positive cell population, consisting of monocytes/macrophages (Mo/Mphi). Furthermore, the elimination of Mo/Mphi attenuated IL-12 production in PBMC. ABH-induced IL-12 production was inhibited by anti-CD14 and anti-TLR4 antibodies but not by anti-TLR2 antibody. The activity of ABH was not inhibited by polymyxin B, while the activity of lipopolysaccharide used as a reference was inhibited. Oral administration of ABH enhanced natural killer (NK) activity in the spleen. These findings suggest that ABH activated Mo/Mphi in a manner dependent on CD14/TLR4 and NK activity.

White spot syndrome virus infection in cultured Penaeus vannamei (Boone) in Ecuador with emphasis on histopathology and ultrastructure

Mortalities of cultured shrimp, Penaeus vannamei (Boone), induced by white spot syndrome virus (WSSV) have occurred in Ecuador since May 1999. Three epidemiological surveys in Ecuadorian farms were carried out and showed an apparent association between lower temperature and increased mortality rates in commercial ponds. Infected animals showed a reddish discolouration and lethargy and occasionally, white spots in the exoskeleton. Histopathological studies revealed that infected cells presented nuclear hypertrophy with eosinophilic to basophilic inclusions. In some cases, two other pathologies were observed: (a) lymphoid organ spheroids and (b) cells with pyknotic and karyorrhectic nuclei in the lymphoid organ, haematopoietic tissue, connective tissue, heart and antennal gland. Occasionally pyknotic cells were encapsulated without apparent injury to the adjacent tissue and without melanization. Transmission electron microscopy showed the presence of WSSV particles in the cytoplasm of cells with pyknotic nuclei in the stomach hypodermis. Viral structure and morphogenesis agreed with previous descriptions by other authors in WSSV-infected shrimp. Occasionally, two nucleocapsids within one envelope were present amongst single enveloped nucleocapsids. A long rod-shaped structure that could reach 2.4 microm in length was present in the nuclei of some infected cells.

Detection and characterization of focal liver lesions using superparamagnetic iron oxide-enhanced magnetic resonance imaging: comparison between ferumoxides-enhanced T1-weighted imaging and delayed-phase gadolinium-enhanced T1-weighted imaging

BACKGROUND

Double contrast magnetic resonance (MR) imaging using superparamagnetic iron oxide (SPIO) and gadolinium (Gd) is performed to detect and characterize focal liver lesions. However, this technique is a costly and lengthy process. The purpose of this study was to determine the usefulness of SPIO-enhanced MR imaging including SPIO-enhanced T1-weighted imaging in diagnosing focal liver lesions.

METHODS

Eighty-four focal liver lesions were examined with a 1.5-T MR unit. Transverse precontrast T1- and T2-weighted images and SPIO (ferumoxides)-enhanced T1- and T2-weighted images were obtained, followed by Gd-enhanced T1 -weighted imaging. The Gd set (i.e., precontrast T1- and T2-weighted and delayed-phase gadolinium-enhanced T1-weighted images) and ferumoxides set (i.e., precontrast T1- and ferumoxides-enhanced T1- and T2-weighted images) were reviewed by two independent readers.

RESULTS

More lesions were detected from the ferumoxides set than from the Gd set. Ferumoxides-enhanced T1-weighted imaging showed enhancement patterns of the lesions similar to those of delayed-phase Gd-enhanced T1-weighted imaging. The diagnoses of hepatic metastasis and cyst by the ferumoxides set were similar to those by the Gd set. However, a dynamic study may be inevitable for the diagnosis of hepatocellular carcinoma and hemangioma.

CONCLUSION

The ferumoxides set was useful for the detection of focal hepatic lesions. Ferumoxides-enhanced T1-weighted imaging may replace delayed-phase gadolinium-enhanced T1-weighted imaging in the diagnosis of hepatic metastasis and cysts.

Sediment remediation for ecosystem in eutrophic lakes

The remediation method--namely, a hybrid system combined with DAF and CRM--is studied in this paper for the size reduction of aqua-ecological circulation and for the elution control in lakes. Results show that two effects on water quality purification, the sediment washout effect and the elution control effect, can be induced by this system, and the biota inhabiting the lake is therefore shifted into an oligotrophic aspect, from blue algae to green algae and/or diatoms.

Characteristics of Alkyltrimethoxysilane-Treated Fumed Silicas and Rheological Behavior of Fumed Silica Suspensions in an Epoxy Resin

Fumed silica was surface treated by hexyl (C6), octyl (C8), decyl (C10), hexadecyl (C16), and octadecyl(C18)trimethoxysilanes, and the products were evaluated from various aspects. The amounts of alkyl group introduced on silica surface were all within the range from 22 to 25 mmol/100 g. Such fumed silicas were suspended in an epoxy resin, bisphenol type A, and their rheological properties were measured. The rheological behavior of the silica suspensions was investigated as to steady-state viscosity and dynamic moduli in order to examine the effect of alkyl chain length on interactions of hydrophobic groups on the silica surface. The stronger shear thinning behavior was observed in the surface-modified fumed silica with longer alkyl groups. However, the suspensions of the nontreated fumed silica and the fumed silicas treated by C6 silane showed Newtonian behavior even at the silica concentration of 7 wt%. The dynamic moduli G' of the silica suspensions increased with increasing alkyl chain length. The interaction of hydrophobic groups on the silica surface is mainly attributed to the rheological behavior of fumed silica suspensions in the epoxy resin. Copyright 2001 Academic Press.

A putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 from cotton (Gossypium hirsutum L.) fibers

A novel plant gene CFL1 was cloned from cotton (Gossypium hirsutum L.) fibers by expressed sequence tag (EST) database searching and 5'-RACE (rapid amplification of cDNA ends). This gene shows sequence homology with FKS1 which has been identified as the putative catalytic subunit of the yeast beta-1,3-glucan synthase. It encodes a protein (CFL1p) of 219 kDa with 13 deduced transmembrane helices and 2 large hydrophilic domains, one of which is at the N-terminus and the other in the internal region of the polypeptide. CFL1 displays 21% identity and 41% similarity to FKS1 at the amino acid level over its entire length, with 31% identity and 52% similarity for the hydrophilic central domain. Using RNA and protein blot analysis, CFL1 was found to be expressed at higher levels in cotton fibers during primary wall development. CFL1 also had a strong expression in young roots. Using a calmodulin (CaM)-gel overlay assay, the hydrophilic N-terminal domain of CFL1p was shown to bind to CaM, while the hydrophilic central domain did not. A putative CaM-binding domain, 16 amino acids long, was predicted in the hydrophilic N-terminal domain. Moreover, a product-entrapment assay demonstrated that a protein associated with an in vitro-synthesized callose pellet could be labeled by anti-CFL1 antibodies. Our finding suggests that CFL1 is a putative plant homolog of the yeast beta-1,3-glucan synthase subunit FKS1 and could be involved in callose synthesis.

[Usefulness of multiphase helical CT in the diagnosis of pituitary microadenoma]

The purpose of this study was to determine the value of multiphase helical CT (MHCT) in the diagnosis of pituitary microadenoma. Twenty-two patients with clinically suspected microadenoma were examined. Coronal pre-contrast CT was initially carried out. Three series of helical scanning using 1-mm collimation, 1-mm/s table speed, and 1-mm interval reconstruction covering the entire pituitary gland were performed with an intravenous injection of contrast medium. Immediately after MHCT, delayed CECT was performed. Twenty microadenomas (3-10 mm, mean: 5.5 mm) were surgically confirmed. MHCT could depict all 20 tumors, while pre-contrast CT and delayed CECT showed 4 and 12 of 20 tumors, respectively. MHCT was useful in the diagnosis of pituitary microadenoma owing to its high spatial resolution and extensive coverage.

Nonenhanced magnetic resonance imaging of mild acute pancreatitis

BACKGROUND

Computed tomography (CT) is not always effective for demonstrating mild acute pancreatitis, and the intravenous administration of iodine contrast medium is harmful to the inflamed pancreas. The goal of this study was to evaluate the usefulness of nonenhanced magnetic resonance (MR) imaging for the depiction of mild acute pancreatitis.

METHODS

We performed T1-weighted imaging with a short echo time, T2-weighted imaging, and MR cholangiopancreatography (MRCP) in 12 patients with mild acute pancreatitis. Nonenhanced CT and contrast-enhanced CT were always performed before the MR studies.

RESULTS

T1- and T2-weighted MR images using a breath-hold or respiratory-triggered technique produced clearer images of the inflamed pancreas than did CT. Peripancreatic fat necrosis was shown by both methods. Although MRCP demonstrated no abnormalities of the pancreatic duct, it demonstrated stones in the gallbladder and common bile duct.

CONCLUSIONS

Nonenhanced MR imaging was superior to CT for depiction and confirmation of mild acute pancreatitis.

Purification and properties of thiosulfate dehydrogenase from Acidithiobacillus thiooxidans JCM7814

A key enzyme of the thiosulfate oxidation pathway in Acidithiobacillus thiooxidans JCM7814 was investigated. As a result of assaying the enzymatic activities of thiosulfate dehydrogenase, rhodanese, and thiosulfate reductase at 5.5 of intracellular pH, the activity of thiosulfate dehydrogenase was measured as the key enzyme. The thiosulfate dehydrogenase of A. thiooxidans JCM7814 was purified using three chromatographies. The purified sample was electrophoretically homogeneous. The molecular mass of the enzyme was 27.9 kDa and it was a monomer. This enzyme had cytochrome c. The optimum pH and temperature of this enzyme were 3.5 and 35 degrees C. The enzyme was stable in the pH range from 5 to 7, and it was stable up to 45 degrees C. The isoelectric point of the enzyme was 8.9. This enzyme reacted with thiosulfate as a substrate. The Km was 0.81 mM.

Peak blood flow measurement of coronary sinus by cine phase contrast MR imagings: comparison between breath-hold and respiratory compensation techniques

The aim of this study was to assess the feasibility of cine phase contrast (PC) magnetic resonance (MR) imaging for the peak blood flow measurement of the coronary sinus. Conventional PC imaging demonstrated the coronary sinus clearly and the significantly higher peak flow compared with the corresponding values measured with breath-hold fast cine PC imaging techniques at end-inspiration and end-expiration. This study showed the feasibility of conventional cine PC imaging with respiratory compensation in measurement of coronary sinus blood flow.

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging of the brain. Technique for suppression of enhancing venous signal

PURPOSE

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging (BB-FSE) was performed to suppress enhancing venous signal and flow artifacts in the brain without sacrificing the T1-weighted imaging contrast.

MATERIAL AND METHODS

Twenty-five MR imaging sections (17 transverse and 8 coronal images) in 15 patients with various brain diseases were obtained by contrast-enhanced T1-weighted SE and BB-FSE images.

RESULTS

In contrast-enhanced T1-weighted BB-FSE images, venous signal was significantly less and T1-weighted contrast of the brain was more evident. No differences in flow artifacts were found between the two imaging techniques. The interobserver agreements were good for the venous signal and flow artifacts using both techniques.

CONCLUSION

Contrast-enhanced T1-weighted BB-FSE imaging reduced the venous signal in the brain with maintaining T1-weighted contrast. This novel MR technique can be used when the suppression of enhancing venous signal is expected to improve the depiction of enhancing lesions in the brain.

Epidemiological Survey for Hemolytic Streptococci Isolated from Children in Tokyo

During the 20-year period between 1979-1998, a total of 4,176 strains of hemolytic streptococci have been isolated from 20,118 healthy primary school children and little children in Tokyo Metropolitan (Tokubetsuku, Tama and Tosho). Culture of throat swabs every November and the following February during the 20-year period were made and serological grouping and typing for isolates were done by T agglutination method. The results were as follows. 1) Serological group of hemolytic streptococci isolated from children were 3,188 strains (76.3%) for isolates of group A out of total strains of 4,176, 569 strains (13.6%) for isolates group B, 63 strains (1.5%) for isolates of group C and 356 strains (8.5%) for isolates of group G. 2) The most dominant was T12 during 1979-1998, and other relatively frequent serotypes were T28, T1, T4, T6 in that order. These ranks of and the main epidemic serotypes showed a similar trend in the 3 areas. 3) The isolation rates of group A streptococci were 15.9% in Tokubetsuku, 17.1% in Tama and 14.9% in Tosho. The average of 3 areas were 15.8%. 4) The epidemic cases seemed to be caused by group A streptococci were 20 cases, their isolated serotype were 7 cases by T28, 5 cases by T12, 4 cases by T6, 2 cases by T4, each 1 case by T1 and T25. 5) A total of 2,927 strains of group A streptococci were examined for drug sensitivity. All strains were sensitive to beta-lactam group of antibiotics (benzylpenicillin and cephaloridine). Resistant (MIC > or = 25 micrograms/ml) to TC, CP and EM etc. were 740 strains (25.3%) in this study. The incidence of resistant strains were to TC 493 strains (66.6%) out of 740 strains, 81 strains (10.9%) for TC.CP, 72 strains (9.7%) for EM and 66 strains (8.9%) for TC.CP.EM.OL.LCM. TC resistant strains have not varied much through the whole period, but CP and EM resistant strains were very variable by year. Many resistant strains to TC were T4, to EM and multiple drug resistant were T12. 6) The rates of isolates of the same type of group A streptococci in school child individual during for the tests taken twice a year were 12.3%, indicating group A streptococci, according to the duration of the carrier state, seems to be a short period.

Polyurethane membrane as an efficient immobilization carrier for high-density culture of rat hepatocytes in the fixed-bed reactor

A fixed-bed bioreactor with a polyurethane membrane (PUM) as a cell-supporting material was developed for high-density culture of rat hepatocytes. The PUM has a heterogeneous porous structure of micropores (pore size <100 microm) and macropores (pore size >100 microm) with a porosity of 90%. One important feature of a PUM is that the macropores have finger-like structures and their diameters gradually decrease from the upper to the lower layer of the PUM. Most rat hepatocytes were readily immobilized in the micropores of PUM. Immobilized cell densities of 1-3 x 10(7) cells/cm(3) PUM were achieved within 5 min by natural downflow of cell suspension and their immobilization efficiencies were more than 99%. Using a syringe pump, a cell density of 5 x 10(7) cells/cm(3) PUM was achieved with more than 96% immobilization efficiency. Perfusion cultures using this reactor were performed for 7 days without cell leakage. The optimal cell density for albumin secretion was between 2 x 10(7) and 3 x 10(7) cells/cm(3) PUM. Albumin secretion in the perfusion culture was maintained for a relatively long period of time when compared to that in the monolayer culture. The rate of albumin secretion in the perfusion culture was about 50% of that in monolayer culture. Hepatocytes immobilized in PUM were slightly aggregated, but they maintained spherical form individually even after 7 days of cultivation. The above results show that PUM is a promising cell-supporting material for efficient immobilization of high cell density of hepatocytes.

Evidence that endo-1,4-beta-glucanases act on cellulose in suspension-cultured poplar cells

Suspension-cultured poplar (Populus alba) cells produce two distinct endo-1,4-beta-glucanases, one of which is released in the extracellular culture medium and the other localized in their walls. Two cDNA clones, PopCel1 and PopCel2, isolated from a poplar cDNA library, encode the extracellular and the wall-bound endo-1, 4-beta-glucanases, respectively, based upon deduced amino acid sequences. The products of these two genes contained domains conserved in endo-1,4-beta-glucanase (family 9) and showed 91.5% amino acid identity. The levels of both PopCel1 and PopCel2 mRNAs increased during the lag phase of growth and decreased rapidly during the linear phase. After the levels had decreased, they were again increased by addition of sucrose to the culture medium and further enhanced by the addition of 2,4-dichlorophenoxyacetic acid (2,4-D) in the presence of sucrose. The accumulation of the mRNAs was correlated with the solubilization of cello-oligosaccharides. Cello-oligosaccharides and xyloglucan were also solubilized from the wall preparations of poplar cells incubated with enzyme preparations from the extracellular culture medium and walls. An antibody against both PopCel proteins reduced the production of cello-oligosaccharides by the extracellular enzyme by 90% and that by the wall-bound enzyme by 55%, and also prevented xyloglucan solubilization. The results show that the accumulation of poplar endo-1,4-beta-glucanases is regulated indirectly by auxin in the presence of sucrose and can act on cellulose in suspension-cultured poplar cells.

Inhibitory effects of tranilast on the proliferation and functions of human pterygium-derived fibroblasts

PURPOSE

We studied the possibility that tranilast, an antiallergic and antiproliferative drug, may be beneficial for the treatment of pterygium.

METHODS

Pterygium-derived cells were identified by immunohistochemical methods. Growth rate of pterygium-derived cells was determined by using a hemocytometer. Chemotaxis was determined in a microchemotaxis chamber. Pterygium-derived cells were cultured on floating collagen gel, and the contracted diameter was measured. Collagen synthesis by pterygium-derived cells was determined by the collagenase digestive method. Tranilast was added to the culture medium at final concentrations of 0, 12.5, 25, 50, and 100 microg/ml.

RESULTS

Pterygium-derived cells were stained with anti-prolylhydroxylase and anti-alpha-smooth muscle actin, and identified as fibroblasts. Tranilast inhibited the proliferation and chemotaxis of pterygium-derived fibroblasts, and the collagen-gel contraction induced by these cells, but it exerted no inhibitory action on collagen synthesis by pterygium-derived fibroblasts.

CONCLUSION

Tranilast may be useful for suppressing the recurrence and, possibly, the development of pterygium.

[A case of reversed ophthalmic artery flow without occlusion of the internal carotid artery]

BACKGROUND

We report a case of reversed ophthalmic artery (OA) flow showing neither occlusion of the internal carotid artery (ICA) nor ophthalmic symptoms.

CASE

An 82-year-old man had transient blindness in both eyes. After left carotid endarterectomy, ophthalmic symptoms improved in the right and left eyes. Afterwards, he had a relapse in the left eye.

RESULTS

There was no unusual impression in the ophthalmic examinations, but color Doppler imaging showed reduced flow in the left OA, reversal of flow direction in the right OA. The central retinal artery (CRA) and short posterior ciliary arteries (SPCA) were not detected in the left eye but were detected in the right eye. Digital subtraction angiography demonstrated that the right OA was not contrasted with the right ICA, despite there being no stenosis or occlusion of the right ICA.

CONCLUSIONS

We suggest that carotid surgery may affect the ocular circulation of the opposite side, and reversed OA flow as a collateral pathway from the external carotid artery may occur in the absence of carotid artery stenosis. Good circulation of the CRA and SPCA may preclude manifestation of ophthalmic symptoms even if the OA flow is reversed.

[Diagnostic imaging of malignant lymphoma: current usefulness and limitation]

The recent developments of imaging modalities allow us to make a diagnosis of malignant lymphoma, to determine its staging, and to evaluate its response to treatments noninvasively. Especially, CT and MR imagings can visualize almost all organs involved by lymphoma with high spatial and contrast resolutions. However, it is difficult to detect the small diseased lymph nodes and splenic lesions. The tumor viability after treatments can not be accurately evaluated with imaging studies. The coverage of the whole lymph nodes during one examination is not easily achieved, either. The multidetector CT system, fast MR imaging techniques, new MR contrast media, and PET are expected to overcome these difficulties.

Three-dimensional cardiac cine magnetic resonance imaging with an ultrasmall superparamagnetic iron oxide blood pool agent (NC100150)

The purpose of this study was to assess image quality of three-dimensional (3D) cardiac cine magnetic resonance (MR) imaging before and after administration of a T1-shortening ultrasmall superparamagnetic iron oxide blood pool agent (NC100150). 3D cardiac cine MR imaging was performed in 13 volunteers using a radiofrequency-spoiled cardiac-gated 3D cine gradient-echo sequence with short repetition and echo times. Compared with precontrast images, postcontrast images showed no enhancement in fat and skeletal muscle, moderate enhancement in myocardium, and significant enhancement in ventricular cavity. After contrast injection, the signal ratio of the ventricular chamber to the myocardium significantly increased, and dramatic improvements were seen in the quality of the cineangiographic images and the depiction of cardiac valves. This quantitative study has shown that 3D cardiac cine MR imaging using a blood pool agent provided MR ventriculography and cineangiography with excellent image quality.

Cultivation of rat hepatocytes in a medium based on commercially available infusate solutions

The possibility of using commercially available infusate solutions as a culture medium for hepatocytes was investigated in primary monolayer cultures of rat hepatocytes. The addition of Ca2+ to the infusate medium was necessary for hepatocytes to express their albumin secreting ability. The infusate medium supplemented with hormones (10(-7) M insulin and 10(-7) M dexamethasone) and Ca2+ (72.5 mg/l) allowed hepatocytes to produce albumin of an amount comparable to that produced in Williams' E medium. The activity of released lactate dehydrogenase (LDH) was kept at a low level throughout the cultivation in the infusate medium.

Treatment of intracranial nongerminomatous germ-cell tumor by high-dose chemotherapy and autologous stem-cell rescue

Nongerminomatous germ-cell tumor (NGGCT) in the central nervous system (CNS) is still highly lethal. The present study evaluated the outcome of high-dose chemotherapy followed by autologous stem-cell rescue (ASCR). The patients included three cases of choriocarcinoma, two cases of embryonal carcinoma and one case of yolk sac carcinoma. High-dose cisplatin (200 mg/m2), etoposide (1250 mg/m2) and ACNU (150 mg/m2) were administrated in combination with ASCR to patients at complete remission as a result of surgical removal, irradiation, and from four to seven courses of induction chemotherapy. All the patients treated with this therapy were alive from one to seven years after the diagnosis, living with good performance status. The patients have not required any additional treatments after ASCR. The myelosuppression period, characterized by fewer than 500/microl peripheral neutrophils, ranged from 8 to 15 days (median, 11.5 days). Within seven days of ASCR, high fever was found in four patients. Although mild liver dysfunction was found in all patients, renal dysfunction was not observed. Hearing disturbance was found in 50% of the patients. This treatment regime will improve long-term survival for patients with NGGCT.

Fast 3D cardiac cine MR imaging

We describe a technique for three-dimensional cine MR imaging. By using short repetition times (TR) and interleaved slice encoding, volumetric cine data can be acquired throughout the cardiac cycle with a temporal resolution of approximately 80 msec. A T1-shortening agent is used to produce contrast between blood and myocardium. A comparison between the acquisition times of this and several other two-dimensional techniques is presented.

Cloning and characterization of a new exo-cellulase gene, cel3, in Irpex lacteus

A new cellulose-inducible gene (named cel3) was isolated from a strain of the white rot basidiomycete, Irpex lacteus MC-2. The cel3 open reading frame, containing two introns, encodes a polypeptide of 526 amino acids residues with a molecular mass of 55794 Da. Expression of the cel3 gene was induced by various insoluble celluloses and CM-cellulose. Transcription of cel3 was abolished when cells were cultivated in media containing the above cellulosic substrates, but added with glucose, fructose or lactose, while addition of glycerol or mannitol did not affect the cel3 mRNA level. The amino acid sequence of the catalytic domain of the Cel3 protein was homologous to that of fungal exo-type cellulases belonging to family 7 of the glycosyl hydrolases. A phylogenetic study showed that these exo-type cellulases can be clearly separated from family 7 endo-type cellulases.

Metallic artifacts of coronary and iliac arteries stents in MR angiography and contrast-enhanced CT

Metallic artifacts of intravascular stents were assessed with MR angiography and contrast-enhanced spiral CT. Stainless steel showed less metal artifact than tantalum stent in CT. Metallic artifact in coronary and iliac arteries treated with tantalum stent was not remarkable in MR angiography. Contrast-enhanced CT might be preferable to assess patency of arteries treated with stainless steel stent. while MR angiography was useful in depicting intraluminal signal in tantalum stent.

Measuring respiration of cultured cell with oxygen electrode as a metabolic indicator for drug screening

New trend in methods for assessing pharmacological action to bacteria and cell is to measure their metabolic activities induced, while the conventional methods used population growth. We focused on respiration volume as an indicator of cell metabolism, and developed inexpensive disposable oxygen electrode sensor and multi-channel dissolved oxygen meters (DOX-10 and DOX-96KB). Using these instruments, cytotoxicity was measured for 48 hrs and the method showed superior features to conventional methods in its handiness of one step assay, and excellent adaptability to automated systems. Total usability of this oxygen electrode method is being evaluated in bacterial drug susceptibility test, anticancer drug susceptibility test, and alternatives to animal experiment.

Oral administration of leflunomide (HWA486) results in prominent suppression of immunoglobulin E formation in a rat type 1 allergy model

Leflunomide, a drug being developed for use in the treatment of rheumatoid arthritis, was evaluated in an ovalbumin (OVA)-induced rat type 1 allergy model. In a dose of 1 mg/kg/day, it strongly suppressed the formation of OVA-specific IgE, thus preventing the elevation of the plasma histamine level and induction of anaphylactic shock observed after i.v. challenge with OVA. Studies on leflunomide's effects on the secondary antibody response showed that administration during the primary immune response remarkably diminished the secondary antibody responses, except IgM, even without further drug administration. Furthermore, when administered during the secondary response after rechallenge, both the total IgE and OVA-specific IgE serum levels declined rapidly to nearly baseline levels. Although OVA-specific IgG1, IgG2a, and IgM did not decrease from their primary response levels, these classes' secondary responses were strongly suppressed. In an in vitro study, the proliferation and antibody production of OVA-stimulated spleen cells, derived from Brown Norway rats, were strongly inhibited by A77 1726, leflunomide's active metabolite. When uridine was added to the cell culture, this molecule's effect on cell proliferation was completely restored, whereas the antibody production was partially restored. These findings are consistent with data indicating that leflunomide is a dihydroorotate dehydrogenase inhibitor. Taken together, the above findings suggest the therapeutic potential of leflunomide against type 1 allergic diseases.

Purification, characterization and gene analysis of exo-cellulase II (Ex-2) from the white rot basidiomycete Irpex lacteus

A new exo-type cellulase, named exo-cellulase II (Ex-2), was purified from the crude enzyme preparation of Irpex lacteus. Ex-2 was very similar to the previously characterized exo-cellulase I (Ex-1) with respect to enzymatic features such as optimal pH, temperature, heat stability, and catalytic activity. However, Ex-2 exhibited greater pH stability than Ex-1. The molecular mass and carbohydrate content of Ex-2 (56,000, 4.0%) were different from those of Ex-1 (53,000, 2.0%). A cellulase gene (named cel2) encoding both Ex-2 and Ex-1 was isolated from an I. lacteus genomic library. The cel2 gene was found to consist of 1569 bp with an open reading frame encoding 523 amino acids, interrupted by two introns. The deduced amino acid sequences revealed that cel2 ORF has a modular structure consisting of a catalytic domain and a fungal-type cellulose-binding domain (CBD) separated by a serine-rich linker region. The catalytic domain was homologous to those of fungal cellobiohydrolases belonging to family 7 of the glycosyl hydrolases. Northern blot analysis showed that expression of the cel2 gene was induced by various cellulosic substrates and repressed by glucose, fructose, and lactose.