Chondroitin Sulfate Iron Colloid as MR Contrast Agent in Differentiation between Hepatocellular Carcinoma and Adenomatous Hyperplasia

Using a 1.5 T MR imaging unit, T1- and T2-weighted images were obtained before and after i.v. administration of chondroitin sulfate iron colloid (CSIC) in order to differentiate hepatocellular carcinoma (n = 20) from adenomatous hyperplasia without atypia (n = 16). Differentiation was made from the tumor-liver contrast to noise ratio (CNR) and visual evaluation of the nodule, with reference to signal intensity relative to that of the surrounding liver. The CNR of adenomatous hyperplasia was on T1-weighted images significantly decreased after CSIC administration (p < 0.01). On T2-weighted images, there was no significant difference in CNR after CSIC administration. On the other hand, the CNR of hepatocellular carcinoma was significantly increased after CSIC administration on both T1- and T2-weighted images (p < 0.01). CSIC reflects intratumor reticuloendothelial cellular functions, and is therefore useful in differentiating hepatocellular carcinoma from adenomatous hyperplasia without atypia.

Double Contrast MR Imaging with Iron Colloid and Gd-DTPA in Cholangiocellular Carcinoma

Double contrast MR imaging with combined use of chondroitin sulfate iron colloid (CSIC) and Gd-DTPA was attempted in 3 cases of cholangiocellular carcinoma (CCC). In all cases, nonenhanced spin echo T1- and T2-weighted images, and T1-weighted images after i.v. injection of Gd-DTPA were obtained. Within one week, the MR sequences were repeated one hour after i.v. injection of CSIC. Double contrast (CSIC/Gd-DTPA) T1-weighted imaging was evaluated and compared with the other sequences in terms of tumor detectability, tumor spreading and tumor characterization. Double contrast MR imaging was comparable in tumor detectability and superior as to the evaluation of spreading and characterization to the other MR imaging modalities.

Successful closure of intractable tracheoesophageal fistula using a combination of a modified silicon stent and metallic stents

Although surgery is the usual management strategy for acquired benign tracheoesophageal fistula, sometimes this approach is contraindicated or the patient declines surgical management. In this report, we describe a case of a patient with tracheoesophageal fistula at the level of the carina due to bronchial arterial infusion chemotherapy. Closure could not be achieved in response to multiple treatment strategies, including airway stenting, esophageal stenting, occlusion with microcoils, or cyanoacrylate glue. We subsequently achieved closure of this fistula through the combination of a modified silicon stent and metallic stents.

Selective Area Growth of GaN by MOVPE and HVPE

Recent successful results on the selective area growth (SAG) of GaN that has been done by MOVPE and HVPE are shown. The SAG were carried out on MOVPE-grown GaN (0001) / sapphire substrates with lined or dotted SiO2 masks. Sub-micron GaN dot and line structures are fabricated by the SAG in MOVPE, so that smoothly overgrown GaN layers are successfully realized using the epitaxially lateral overgrowth (ELO) technique. The ELO structures are confirmed to be good quality GaN single crystal with a smooth surface, no grain boundaries, and low-dislocation densities. In addition, thick GaN bulk single crystals without any cracks are grown by the SAG in HVPE. Crystalline and optical properties of the GaN bulk are much improved. The reduction in the thermal strain due to the growth on the limited area as well as the ELO are found to be effective to reduce crystalline defects of the GaN bulk single crystals.

Percutaneous radiofrequency lung ablation combined with transbronchial saline injection: an experimental study in swine

To evaluate the efficacy of radiofrequency lung ablation with transbronchial saline injection. The bilateral lungs of eight living swine were used. A 13-gauge bone biopsy needle was inserted percutaneously into the lung, and 1 ml of muscle paste was injected to create a tumor mimic. In total, 21 nodules were ablated. In the saline injection group (group A), radiofrequency ablation (RFA) was performed for 11 nodules after transbronchial saline injection under balloon occlusion with a 2-cm active single internally cooled electrode. In the control group (group B), conventional RFA was performed for 10 nodules as a control. The infused saline liquid showed a wedge-shaped and homogeneous distribution surrounding a tumor mimic. All 21 RFAs were successfully completed. The total ablation time was significantly longer (13.4 +/- 2.8 min vs. 8.9 +/- 3.5 min; P = 0.0061) and the tissue impedance was significantly lower in group A compared with group B (73.1 +/- 8.8 Omega vs. 100.6 +/- 16.6 Omega; P = 0.0002). The temperature of the ablated area was not significantly different (69.4 +/- 9.1 degrees C vs. 66.0 +/- 7.9 degrees C; P = 0.4038). There was no significant difference of tumor mimic volume (769 +/- 343 mm(3) vs. 625 +/- 191 mm(3); P = 0.2783). The volume of the coagulated area was significantly larger in group A than in group B (3886 +/- 1247 mm(3) vs. 2375 +/- 1395 mm(3); P = 0.0221). Percutaneous radiofrequency lung ablation combined with transbronchial saline injection can create an extended area of ablation.

A randomized phase II trial comparing carboplatin pleurodesis with cisplatin pleurodesis in patients with stage IIIB/IV non-small cell lung cancer (NSCLC) with malignant pleural effusions (MPE)

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Background: We previously reported that carboplatin pleurodesis in patients with advanced lung adenocarcinoma with MPE, renal insufficiency, and poor performance status (PS) was an effective palliative therapy. However, the efficacy and toxicity profile of carboplatin pleurodesis in patients with NSCLC with MPE in comparison with those of cisplatin pleurodesis have not been reported. Methods: Thirty patients with stage IIIB/IV NSCLC accompanied with MPE who did not have an indication for systemic chemotherapy because of poor PS more than 2 were randomized to carboplatin pleurodesis (target area under the curve as 5 μg-min/ml using Calvert’s formula) and cisplatin pleurodesis (80 mg/m2) in a single-blind and controlled trial. Enrollment took place between Oct 2004 and Dec 2005. Primary efficacy endpoints were the best confirmed response rate, time to progression (TTP) in controlling MPE and adverse effects. Results: Fifteen of 30 patients were treated by carboplatin pleurodesis, and resting 15 of 30 patients were treated by cisplatin pleurodesis to control MPE. The response rate in carboplatin pleurodesis was not statistically different from that for patients in cisplatin pleurodesis (P = .226). The use of anticancer drugs for pleurodesis was not significantly associated with response rate in logistic regression analysis (relative risk = 14.2, 95% CI: 0.6–320.5, P = .095). Median TTP in carboplatin pleurodesis was not different from that in cisplatin pleurodesis (96 days vs 83 days). The use of carboplatin for pleurodesis (P = .016) and gender (P = .005) were associated with prolongation of TTP in the Cox regression method. Kaplan-Meier analysis showed that the progression free probability curve in carboplatin pleurodesis was not different from that in cisplatin pleurodesis (P = .275). The rate of Grade 3 thrombocytopenia in carboplatin pleurodesis (25%) was higher than that in cisplatin pleurodesis (0%), but there was no statistical significance (P = .096). Conclusions: Carboplatin pleurodesis and cisplatin pleurodesis may be feasible and acceptable toxicity profiles.

No significant financial relationships to disclose.

Activation of mu-opioid pathway is associated with the canceling effect of footshock stimulus on the restraint stress-induced inhibition of small intestinal motility in rats

We previously reported that small intestinal motility was significantly inhibited by restraint stress, but not by footshock stress. In the present study, we found that plasma beta-endorphin levels were more significantly elevated by footshock stress than restraint stress, and that preloading of footshock stimulus canceled the inhibition of small intestinal motility by restraint stress. Pretreatment with the mu-opioid receptor antagonist naltrexone significantly attenuated this canceling effect of footshock stimulus. These results suggest that footshock stimulus may cancel the inhibition of small intestinal motility by restraint stress via activation of mu-opioid receptors.

Beta3-adrenoceptor is involved in the inhibition of small intestinal motility due to restraint stress in rats

We have reported that acute restraint stress inhibits small intestinal motility in rats. In order to clarify this inhibitory mechanism, we examined the effects of alpha- and beta-adrenergic antagonists on the inhibition of small intestinal motility induced by restraint stress. This inhibition underwent recovery by propranolol (beta1/beta2-antagonist) or SR59230A (beta3-antagonist), but not by atenolol (beta1-antagonist), ICI-118,551 (beta2-antagonist), prazosin (alpha1-antagonist) or yohimbine (alpha2-antagonist). These results suggest that beta3-adrenoceptors play an important role in the inhibition of small intestinal motility caused by restraint stress.

Synthesis and evaluation of novel 2-oxo-1,2-dihydro-3-quinolinecarboxamide derivatives as potent and selective serotonin 5-HT4 receptor agonists

A series of 8'-substituted N-(endo-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamides were synthesized. The 5-HT4 receptor agonistic activity was evaluated using the isolated guinea pig ileum preparation. Of the compounds synthesized, N-(endo-8-(3-hydroxypropyl)-8-azabicyclo[3.2.1]oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (15a, TS-951) exhibited the most potent serotonin 5-HT4 receptor agonistic activity. This compound had a high affinity for the serotonin 5-HT4 receptor although it had no affinities for other broad spectrum receptors. Furthermore, it remarkably enhanced gastrointestinal motility in conscious fed dogs without unfavorable effects that non-selective serotonin 5-HT4 receptor agonist has. TS-951 may be useful in improving gastrointestinal dysfunction.

Discordant uptake of Tc-99m PMT and Tc-99m GSA by two hepatocellular carcinoma lesions

Tc-99m PMT and Tc-99m GSA can be taken up by hepatocellular carcinoma (HCC), but there has been no report concerning HCC showing accumulation of both of Tc-99m PMT and Tc-99m GSA. In this paper we describe a case of two simultaneously developed HCCs, one of which took up both tracers but the other took up neither of them.

Synthesis and evaluation of novel 2-oxo-1,2-dihydro-3-quinolinecarboxamide derivatives as serotonin 5-HT4 receptor agonists

A series of N-azabicycloalkyl-1-alkyl-2-oxo-1,2-dihydro-3-quinolinecarboxamides were synthesized and tested for serotonin 5-HT4 receptor-stimulating effects in the regulation of electrically-evoked contraction in guinea pig muscle. Among them, N-azabicycloalkyl-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (8c, 9c, 10c, 11c, 12c) exhibited potent serotonin 5-HT4 receptor-stimulating activity. The most potent compound, N-(endo-8-methyl-8-azabicyclo[3.2.1 oct-3-yl)-1-isopropyl-2-oxo-1,2-dihydro-3-quinolinecarboxamide (8c, ED50 = 36.3 nMi), was seven times as active as cisapride, while 8c had no affinity for 5-HT1A, 5-HT1D, D2, muscarinic M2 or muscarinic M3 receptors even at 10 microM. Compound 8c stimulated digestive tract motility in conscious fed dogs (1.0 mg/kg p.o.).

A fluorescent-labeled oligopeptide for monitoring PKA-mediated phosphorylation

A fluorescent-labeled oligopeptide (DACM-CLRRASLK-fluorescein), containing a consensus amino acid sequence (RRXSL) of cyclic AMP (cAMP) dependent protein kinase A (PKA) substrate-proteins, was designed. The fluorescent peptide was a good substrate of PKA, and the phosphorylation of its serin residue caused an intensive change in fluorescent intensity. We expect that the peptide will be useful as a fluorescent indicator for monitoring PKA activity in living cells.

The design of cyclic AMP--recognizing oligopeptides and evaluation of its capability for cyclic AMP recognition using an electrochemical system

A novel 17-mer peptide ligand for cyclic AMP was designed using the amino acid sequences of essential subsites in various cyclic AMP-dependent protein kinase (protein kinase A) families. The Au disk electrode, which was modified with the designed 17-mer oligopeptide, responded to cyclic AMP but virtually did not respond to any other cyclic nucleotides using the ion channel sensor mechanism. On the other hand, a scrambled peptide, which had the same amino acid composition as and had an amino acid sequence different from the 17-mer oligopeptide, did not respond to any nucleotides. This indicates that the designed 17-mer peptide actually acted as a selective ligand for cyclic AMP. This ligand-designing strategy using peptide sequences in target-binding proteins may possibly be extended to the design of peptide ligands for other second messengers.

Intraosseous pneumatocyst of the scapula

Intraosseous pneumatocyst is a gas-containing cyst-like lesion that occurs most frequently in the ilium, sacrum or vertebrae. We present a case involving the left scapula that was found incidentally on CT. To our knowledge, intraosseous pneumatocyst of the scapula has not been previously reported.

Clinical significance of anticentromere antibodies in patients with systemic lupus erythematosus

OBJECTIVE

To clarify the clinical significance of anticentromere antibodies (ACA) in patients with systemic lupus erythematosus (SLE).

METHODS

Two hundred sixteen patients with SLE who were treated in our department were surveyed cross sectionally for the presence of ACA using indirect immunofluorescence on HEp-2 cell lines. ACA were identified by their discrete speckled pattern. Antibodies to the major centromere protein, CENP-B, were also studied with ELISA. Serial determinations of anti-CENP-B were carried out using stored serum samples, if available.

RESULTS

ACA were recognized in 12 (5.6%) patients with SLE. All patients were receiving steroid therapy, with a mean dose of prednisolone of 14.4 mg/day. These patients also tested positive for anti-CENP-B with high titers despite the low serological disease activity in most. Three or more CREST features were observed in 2 patients and 2 others had no such features. Both patients without CREST features had a relatively short disease duration. The age at onset of SLE was significantly higher and Raynaud's phenomenon was more frequent in patients with ACA than in patients without ACA. In 8 of 10 patients tested, retrospective analysis using stored sera revealed no consistent change in anti-CENP-B titers over time.

CONCLUSION

The presence of ACA in patients with SLE is apparently more frequent than previously believed. Patients with SLE with ACA may be a distinct subgroup. A longterm followup is warranted to fully determine the clinical significance of ACA in patients with SLE.

Prevalence of hypoxemia in 102 Japanese patients with alcoholic and nonalcoholic cirrhosis

OBJECTIVE

Liver cirrhosis is often accompanied by arterial hypoxemia in the absence of cardiopulmonary disease. The aim of this study was to investigate the relationship between various clinicopathological conditions and the hypoxemia seen in Japanese patients with liver cirrhosis.

METHODS

In 102 consecutive patients with alcoholic (N = 45) and nonalcoholic (N = 57) cirrhosis not associated with cardiopulmonary disease, we performed lung perfusion scintigraphy, contrast echocardiography, and arterial blood gas analysis and measured oxygen consumption.

RESULTS

No abnormality was seen in pulmonary blood flow in cirrhotic patients, but 38 (38%) of them had a decreased partial pressure of oxygen (PaO2). The hypoxemic patients did not show any pulmonary signs or symptoms. The hypoxemia was not associated with the Child-Pugh grade, and was observed in 32 (71%) of the 45 alcoholic patients but in only six (11%) of the 57 nonalcoholic patients (p < 0.001). Oxygen consumption was significantly higher in the alcoholic group than in the nonalcoholic group (p < 0.0001), and a high incidence of oxygen consumption was seen in all 45 (100%) of the alcoholic patients and in 34 (60%) of the nonalcoholic subjects, the difference being significant (p < 0.01). The relationship between oxygen consumption and PaO2 in the 102 cirrhotic patients showed an inverse correlation (r = -0.85, p < 0.0001). Among the alcoholic patients, the incidence of hypoxemia did not differ between the 33 smokers and the 12 nonsmokers. After 1 wk of abstinence from alcohol a significant increase (p < 0.0001) in the PaO2 was seen in 14 of 19 patients with alcoholic cirrhosis.

CONCLUSIONS

We conclude that the hypoxemia in Japanese patients with liver cirrhosis occurs mainly in drinking alcoholic patients, presumably due to an increased oxygen consumption by alcohol.

Role of peroxynitrite in airway microvascular hyperpermeability during late allergic phase in guinea pigs

We investigated the role of peroxynitrite, which is formed by a rapid reaction between nitric oxide (NO) and superoxide anion (O(2)(-)), in the airway microvascular hyperpermeability during the late allergic response (LAR) in sensitized guinea pigs in vivo. The occurrence of LAR was assessed as a 100% increase in the transpulmonary pressure, which was monitored by the esophageal catheter technique. Airway microvascular permeability was assessed by Monastral blue dye trapping between the endothelium using an image analyzer. In the LAR phase (4 to 6 h after antigen inhalation), microvascular hyperpermeability and eosinophil infiltration within the airway wall were observed. NO production and xanthine oxidase (XO)/xanthine dehydrogenase activity, which are responsible for O(2)(-) production, were enhanced during the LAR. Peroxynitrite formation assessed by nitrotyrosine immunostaining was also exaggerated at that time. The microvascular hyperpermeability during the LAR was largely reduced by NO synthase inhibitor (L-NAME, 72.7% inhibition; p < 0.05), XO inhibitor (AHPP, 60.8% inhibition; p < 0. 05) and peroxynitrite scavenger (ebselen, 81.0% inhibition; p < 0. 05). L-NAME had a small but significant inhibitory effect on airway eosinophil accumulation, but AHPP and ebselen had no effect. These results suggest that excessive production of O(2)(-) and NO occurs in the LAR. These two molecules appear to cause airway microvascular hyperpermeability via peroxynitrite formation.

Possible neural mechanisms involved in footshock stress-induced enhancement of exploratory behavior in mice

The effect of inescapable footshock stress on open-field activity, as measured by the number of ambulations, was studied in male mice. Ambulations significantly increased after footshock stress, the most significant effect appeared after 20 min-stimulation and the effect decreased as footshock time lengthened. The footshock stress-induced enhancement of ambulation was inhibited by haloperidol (0.2, 0.5 and 1 mg/kg), phentolamine (5 and 10 mg/kg), mianserin (20 mg/kg), atropine (0.5, 1 and 2 mg/kg), naltrexone (10 mg/kg) and MK-801 (0.05, 0.1 and 0.2 mg/kg), but was not influenced by propranolol (5, 10 and 20 mg/kg) or diazepam (1, 2 and 5 mg/kg). Haloperidol (0.5 and 1 mg/kg) and mianserin (5, 10 and 20 mg/kg) also exerted an inhibitory effect on non-stressed normal mice. These results suggest that dopaminergic, alpha-adrenergic, cholinergic, opioidergic and N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission systems are involved in the footshock stress-induced ambulatory activation.

Induction of nitric oxide synthase by lipopolysaccharide inhalation enhances substance P-induced microvascular leakage in guinea-pigs

Inducible nitric oxide (NO) synthase (iNOS)-mediated hyperproduction of NO in airways has been reported in asthmatic patients. However, the role of NO in the pathogenesis of asthma has not yet been fully elucidated. The aim of this study was to examine whether the iNOS-derived NO affects airway microvascular leakage, one of the characteristic features of asthmatic airway inflammation. Guinea-pigs were exposed to lipopolysaccharide (LPS) (1 mg x mL(-1)) by inhalation in order to induce iNOS in the airways, and the histochemical staining of reduced nicotinamide-adenine dinucleotide phosphate (NADPH)-diaphorase activity was determined 5 h after the inhalation to confirm the iNOS induction. Airway microvascular leakage to subthreshold doses of substance P (0.3 microg x kg(-1), i.v.) was also examined in the absence and presence of an iNOS inhibitor (aminoguanidine) in LPS- or saline-exposed (control) animals using Evans blue dye and Monastral blue dye. In the LPS-exposed animals, increased NADPH-diaphorase activity was observed in the airway microvasculature compared with the control animals. Substance P caused significant airway microvascular leakage assessed by Evans blue dye in all airway levels in the LPS-exposed animals but not in the control group. This was also confirmed by Monastral blue dye extravasation. Aminoguanidine abolished this LPS-induced enhancement of plasma leakage to substance P without changing the systemic blood pressure. These results may suggest that inducible nitric oxide synthase-derived nitric oxide is capable of potentiating neurogenic plasma leakage in airways.

Protective effects of interleukin-10 on diaphragm muscle in a septic animal model

The effects of Interleukin (IL)-10 intravenous injection after endotoxin administration on diaphragm muscle were studied using Wistar rats. The animals were divided into two treatment groups: A saline + endotoxin group as control and an IL-10 + endotoxin group. E. coli endotoxin (10 mg/kg) was injected intraperitoneally 5 minutes after saline or IL-10 (1250 U, 0.25 mg) injection. The force-frequency curves, twitch kinetics and fatigability were measured at 0 and 4 hours after endotoxin injection. In the saline + endotoxin group, the force-frequency curves and half relaxation time were significantly decreased at 4 hours (p < 0.001 and p < 0.05, respectively) compared to those at 0 hour. In the IL-10 + endotoxin group, the decrement in the force-frequency curves by endotoxin was prevented at 4 hours compared to that at 0 hour. Nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry showed positive staining in the saline + endotoxin at 4 hours, but there was no significant staining at 0 or 4 hours in the IL-10 + endotoxin group. These data suggest that IL-10 prevents the deterioration of contraction induced by endotoxin by inhibiting nitric oxide production in the diaphragm muscle.

Histamine-induced calcium mobilization in single cultured cells expressing histamine H1 receptors: a relationship between its sensitivity and the density of H1 receptors

Stimulation of histamine H1 receptors initiates the hydrolysis of phosphatidylinositides and results in the production of inositol (1, 4,5)-triphosphate and intracellular Ca2+ mobilization. Although the mechanism for signal transduction via the H1 recptor has been extensively investigated, little is known about the correlation between the sensitivity of histamine-induced Ca2+ mobilization and the density of H1 receptors in cultured cells. Cytosolic free Ca2+ concentration ([Ca2+]i) after stimulation by histamine was monitored in single CHO and rat C6-glioma cells stably expressed with H1 receptors and astrocytoma 1321N1 cells using the Ca2+-sensitive dye Indo-1 and dynamic single cell imaging techniques (ACAS 570 laser cytometer). Both of the H1 receptor-expressed CHO cells and C6-glioma cells were over 10 times more sensitive to histamine than astrocytoma 1321N1 cells in which H1 receptors were naturally present. The density of H1 receptors in the transfected cells was also more than 10-fold that of 1321N1 cells. In addition, inhibition of intracellular Ca2+-ATPase by thapsigargin elicited an increase in [Ca2+]i in H1 receptor-overexpessed cells and astrocytoma 1321N1 cells with similar sensitivity. These data suggest that the sensitivity of Ca2+ mobilization by histamine in these cells was correlatively augmented with the increase in the density of H1 receptors.

Effects of L-NAME and L-arginine on diaphragm contraction in a septic animal model

The effects of nitric oxide on diaphragm contraction after endotoxin administration were studied in Wistar rats. The animals were divided into seven treatments: a saline-injected group as control, three groups injected with L-NAME (0.01, 0.1, 1 mg/kg) and three groups injected with L-arginine (1, 10, 100 mg/kg). Escherichia coli endotoxin was injected into the peritoneal cavity 15 min later. Twitch kinetics and force-frequency curves were measured 0, 2, and 4 hr after endotoxin injection. In the control group, the force-frequency curves significantly decreased from 0 hr to 4 hr. In the L-NAME group, the force-frequency curves at 4 hr showed significant increases in a dose-dependent manner. In the L-arginine group, the force-frequency curve with 100 mg/kg at 4 hr showed a significant increase. There was no consistent change in the contraction time, half relaxation time, or fatiguability. NADPH diaphorase histochemistry performed on diaphragm muscle samples 4 hr after endotoxin injection showed positive in the control and L-arginine group, but was only weakly observed in L-NAME group. These data suggest that nitric oxide contributes to the endotoxin induced diaphragm contractile deterioration.

Impairment of neural nitric oxide-mediated relaxation after antigen exposure in guinea pig airways in vitro

Nitric oxide (NO), a neurotransmitter of inhibitory nonadrenergic noncholinergic (iNANC) nerves in airways, is a radical with a short half-life, and its function may be modified by airway inflammation. To test this hypothesis, we examined whether airway allergic inflammation affects iNANC responses mediated by NO in guinea pigs in vitro. Animals sensitized with ovalbumin (OA) were challenged with 0.03% OA (OA group) or saline (saline group) by inhalation on 3 consecutive days. On the day after the final challenge, iNANC responses elicited by electrical field stimulation (2 to 16 Hz) or relaxation responses to 3-morpholinosydnonimine (SIN-1), 10(-8) to 10(-4) M, were obtained in the tracheal strips precontracted by histamine (3 x 10(-6) M) in the presence of atropine and propranolol (both 10(-6) M). The INANC responses of the OA group were significantly attenuated compared with those of the saline group (p < 0.05), and the inhibitory effect of a NO synthase (NOS) inhibitor, Nm-nitro-L-arginine methyl ester, on the INANC responses was abolished in the OA group. SIN-1-induced tracheal smooth muscle relaxation was also significantly affected by antigen exposure (p < 0.05), the effect of which disappeared in the presence of a NO scavenger, carboxy PTIO (3 x 10(-6) M). The impairment of the INANC responses after antigen exposure was significantly restored by superoxide dismutase (1,000 U/ml), especially at lower frequencies. Histochemical demonstration of NADPH-diaphorase-positive nerves representing neural NOS density was not different between the two groups. These results suggest that allergic airway inflammation impairs neural NO-induced relaxation, presumably by inhibiting the access of neural NO to the airway smooth muscle.

Role of endogenous nitric oxide in airway microvascular leakage induced by inflammatory mediators

This study examines the role of endogenous nitric oxide (NO) in airway microvascular leakage induced inflammatory mediators, which play an important role in asthmatic airways. Guinea-pigs were anesthetized and mechanically-ventilated with monitoring of arterial blood pressure, and airway microvascular leakage induced by intravenous injection of substance P (SP), leukotriene D4 (LTD4) and histamine was evaluated using Evans blue dye and Monastral blue dye in the presence and absence of the NO synthase inhibitors, L-NG-nitroarginine methyl ester (L-NAME) and L-NG-monomethyl arginine (L-NMMA). The effect of a soluble guanylate cyclase inhibitor, LY83583, on SP-induced dye leakage was also examined. Intravenous injection of SP (1 microgram.kg-1), LTD4 (1 microgram.kg-1) and histamine (100 micrograms.kg-1) significantly increased dye extravasation at all airway levels. Pretreatment with L-NAME (10 mg.kg-1 i.v.) and L-NMMA (100 mg.kg-1 i.v.) significantly inhibited SP-induced extravasation, and L-arginine (100 mg.kg-1 i.v.) reversed L-NAME-induced inhibition. L-NAME (10 mg.kg-1 i.v.) also significantly inhibited LTD4-induced dye extravasation only in central airways, and this inhibitory effect was abolished by a neurokinin-1 (NK1) antagonist, FK888 (10 mg.kg-1 i.v.) pretreatment. Histamine-induced dye extravasation was not affected by L-NAME. LY83583 (2.5 and 7.5 mg.kg-1 i.v.) partially but significantly reduced SP-induced dye leakage. These results suggest that endogenous nitric oxide plays a role in neurokinin-1 receptor-mediated airway microvascular leakage, and presumably involves the guanylate cyclase pathway.

Histidine decarboxylase expression in mouse mast cell line P815 is induced by mouse peritoneal cavity incubation

Phenotype of P815 mouse mast cells changes markedly during culture in the peritoneal cavity of syngenic BDF1 mice. The cells, cultured for 1 week in the peritoneal cavity of syngenic BDF1 mice, proliferate and express high levels of L-histidine decarboxylase (HDC) and mouse mast cell protease (MMCP)-6 mRNAs, indicating the ability of P815 cells to differentiate toward mature connective tissue mast cells. Peritoneal fluid aspirated from P815-inoculated BDF1 mouse and added to cultured P815 cells in vitro was also found to induce HDC mRNA expression, suggesting that at least some of the humoral factors in the peritoneal fluid induce HDC mRNA transcription. Among the erythroid transcription factors, P815 cells expressed GATA-2 but not GATA-1 mRNA before and after the intraperitoneal incubation. In contrast, the expression of NF-E2 subunit p45 disappeared, while expression of subunit mafK was markedly reduced after incubation. Cotransfection assays using HDC-luciferase reporter and p45 and/or mafK expression constructs showed that NF-E2 affects the transactivation of HDC gene. These results suggest that NF-E2 is also an important transcription factor in mast cell differentiation.

Helicobacter pylori infection in patients with gastric carcinoma in biopsy and surgical resection specimens

BACKGROUND

The discrepancy between the high seropositivity for Helicobacter pylori (H. pylori) and the low diagnostic yield of H. pylori organism in gastric biopsies of patients with gastric carcinoma has yet to be clarified. The present study attempted to clarify this controversial point by performing a comparative evaluation between the detection rate of H. pylori in biopsy and in surgical specimens.

METHODS

The presence of H. pylori in biopsy samples from 50 patients with gastric carcinoma and 50 age-matched controls was evaluated histologically. Six histologic sections were obtained from gastric noncancerous areas and the presence of H. pylori was evaluated in those H. pylori negative patients who underwent gastrectomy.

RESULTS

H. pylori was positive in 35 of 50 controls (70%). In biopsy samples, H. pylori was detected in 29 of 37 patients (78.4%) with early gastric carcinoma, 7 of 13 (53.8%) with advanced carcinoma, 16 of 23 (69.6%) with intestinal type of gastric carcinoma, and 20 of 27 (74.1%) with diffuse type of carcinoma. Studies carried out in gastrectomy specimens increased the diagnostic yield of H. pylori to 33 (89.2%), 12 (92.3%), 19 (82.6%), and 26 (96.3%) in patients with early, advanced intestinal, and diffuse types of gastric carcinoma, respectively. Overall, H. pylori was positive in 36 biopsy specimens (72%) and 45 gastrectomy specimens (90%). Namely, the detection of H. pylori infection was significantly higher in patients with gastric carcinoma using gastrectomy specimens than in patients with gastric carcinoma using biopsy specimens only (P < 0.05).

CONCLUSIONS

These results indicate that the actual prevalence of H. pylori in patients with gastric carcinoma is considerably higher than that previously reported.

Endogenous nitric oxide modifies antigen-induced microvascular leakage in sensitized guinea pig airways

To examine the role of endogenous nitric oxide in allergic airway inflammation, we investigated the effect of a nitric oxide synthase inhibitor, N omega-nitro-L-arginine methyl ester (l-NAME), on antigen-induced airway microvascular leakage in actively sensitized guinea pigs by using Evans blue dye. Three weeks after sensitization with ovalbumin (10 micrograms), the tracheas were cannulated, and lungs were artificially ventilated. Animals were pretreated with atropine and propranolol (both 1 mg/kg, intravenously) to avoid neural modification. Ovalbumin inhalation (3 mg/ml, 1 minute) challenge caused significant microvascular leakage in all airways portions, which was significantly suppressed in a dose-dependent manner by pretreatment with intravenous injection of L-NAME (1 and 10 mg/kg) but not with the inactive enantiomer D-NAME (10 mg/kg). This inhibition by L-NAME was significantly reversed by co-administration of L-arginine (100 mg/kg, intravenously). Pretreatment with a vasoconstrictor, phenylephrine (20 micrograms/kg, intravenously), had no inhibitory effects on antigen-induced airway microvascular leakage despite increasing systemic blood pressure. Inhalation of representative mast cell-derived mediators, histamine (2 mg/ml, 1 minute) or leukotriene D4 (5 micrograms/ml, 1 minute), produced significant microvascular leakage in all airways. L-NAME (10 mg/kg, intravenously) partially but significantly inhibited leukotriene D4-induced leakage, whereas histamine-induced leakage was not affected. These results suggest that endogenous nitric oxide acts to increase airway microvascular leakage after airway allergic reaction.

A neurokinin 1-receptor antagonist improves exercise-induced airway narrowing in asthmatic patients

Recent reports suggest the involvement of vascular phenomena in exercise-induced asthma. Sensory neuropeptides, such as substance P (SP), which causes airway vascular dilatation and plasma leakage, have been demonstrated to play a role in hyperpnea-induced airway narrowing in animal studies. The purpose of this study was to investigate the importance of tachykinins in exercise-induced airway narrowing in patients with asthma using a selective neurokinin 1-receptor (NK1-receptor) antagonist, FK-888. In a double-blind, placebo-controlled, crossover trial, nine subjects with stable asthma were given FK-888 (2.5 mg) or placebo by inhalation 20 min before each exercise at a level previously demonstrated to cause a fall of at least 40% in specific airway conduction (SGaw). Inhalation of FK-888 had no significant effect on baseline SGaw. While the recovery from exercise-induced airway narrowing was significantly faster after treatment with FK-888 the area under the curve for SGaw during the 50 min after exercise was significantly reduced (p<0.05) and the time taken for the SGaw to recover to within 65% of baseline after exercise was also significantly shorter with FK-888 than the placebo (p<0.05). However, treatment with FK-888 did not significantly attenuate the maximal fall in SGaw. These results suggest that NK1-receptor-mediated mechanisms are involved in the recovery phase of exercise-induced airway narrowing. The possible mechanisms of these phenomena are discussed.

Double contrast MR imaging with iron colloid and Gd-DTPA in cholangiocellular carcinoma

Double contrast MR imaging with combined use of chondroitin sulfate iron colloid (CSIC) and Gd-DTPA was attempted in 3 cases of cholangiocellular carcinoma (CCC). In all cases, nonenhanced spin echo T1- and T2-weighted images, and T1-weighted images after i.v. injection of Gd-DTPA were obtained. Within one week, the MR sequences were repeated one hour after i.v. injection of CSIC. Double contrast (CSIC/Gd-DTPA) T1-weighted imaging was evaluated and compared with the other sequences in terms of tumor detectability, tumor spreading and tumor characterization. Double contrast MR imaging was comparable in tumor detectability and superior as to the evaluation of spreading and characterization to the other MR imaging modalities.

Single breath-holding three-dimensional magnetic resonance portography with bolus injection of Gd-DTPA in subjects with normal liver: a comparison with two-dimensional time-of-flight technique

Two-dimensional time-of-flight (2D-TOF) magnetic resonance (MR) portography tends to produce general image degradation owing to the phase discrepancy caused by multiple breath-holding. To solve this problem, three-dimensional (3D)-MR portographies were reconstructed from image data acquired with a bolus injection of Gd-DTPA with single breath-holding in 20 subjects with normal liver function. 2D-TOF MR portographies were obtained beforehand for the comparison. All the images were displayed in a cine mode for the two MR angiographic techniques. Visualization was assessed as positive when the vessel was visualized without disruption. 3D-MR portography produced a positive rate of over 80% for all but the left first-order branch. With the 2D-TOF techniques, however, only the portal trunk and left second-order branches were visualized at this rate. The positive rate for most portal branches was significantly higher with 3D-MR portography than with the 2D-TOF technique. In conclusion, 3D-MR portography makes it possible to depict the portal venous system without disruption using a short measurement time with single breath-holding and has the potential to become a powerful method for abdominal MR angiography.

Preparation and applicability of Sarcocystis cruzi antigens and their anti-S. cruzi rabbit sera for serodiagnosis of bovine sarcocystosis

Sarcocystis cruzi antigens and their antisera were prepared for the seroimmunological diagnosis of bovine sarcocystosis. Fresh S. cruzi cysts directly removed from cardial muscle of slaughtered cattle were digested with trypsin to release bradyzoites. By twelve cycles of freezing at-22 degrees C and thawing at 37 degrees C, bradyzoites were let to leach out soluble material. The soluble antigens were inoculated four times to rabbits at a dose of 343 micrograms protein and anti-S. cruzi sera were prepared with blood of the rabbits. Gel immunodiffusion test showed no cross-reaction between the present antigens and any of anti-Toxoplasma gondii, -Hammondia hammondi and -Besnoitia wallacei rabbit sera. Avidin-biotin complex immunoperoxidase (ABC) technique with the present anti-S. curzi rabbit sera showed clear positive reaction against S. cruzi cysts in the muscular sections of infected cattle.

Three-dimensional black blood MR angiography of the liver during breath holding. A comparison with two-dimensional time-of-flight MR angiography

In 2-D time-of-flight MR angiography (2-D TOF MRA) of the liver, artifacts caused by respiratory motion are unavoidable. Therefore, a 3-D black blood MRA of the liver was attempted in 7 healthy volunteers, using a 3-D gradient echo sequence which allows imaging during breath holding. 2-D TOF MRA was performed as well. In all subjects, 3-D MRA allowed visualization of the trunk, 1st-, and 2nd-order branches of the portal vein without interruption. Right 3rd-order branches were visualized without interruption in 6 of 7 subjects (85%). However, with 2-D MRA, the transverse portion of the left main portal vein could not be visualized in any subject, and the periphery of the portal vein was less clear than with 3-D MRA.

Chondroitin sulfate iron colloid as MR contrast agent in differentiation between hepatocellular carcinoma and adenomatous hyperplasia

Using a 1.5 T MR imaging unit, T1- and T2-weighted images were obtained before and after i.v. administration of chondroitin sulfate iron colloid (CSIC) in order to differentiate hepatocellular carcinoma (n = 20) from adenomatous hyperplasia without atypia (n = 16). Differentiation was made from the tumor-liver contrast to noise ratio (CNR) and visual evaluation of the nodule, with reference to signal intensity relative to that of the surrounding liver. The CNR of adenomatous hyperplasia was on T1-weighted images significantly decreased after CSIC administration (p < 0.01). On T2-weighted images, there was no significant difference in CNR after CSIC administration. On the other hand, the CNR of hepatocellular carcinoma was significantly increased after CSIC administration on both T1- and T2-weighted images (p < 0.01). CSIC reflects intratumor reticuloendothelial cellular functions, and is therefore useful in differentiating hepatocellular carcinoma from adenomatous hyperplasia without atypia.

Haplotypes identified by DNA polymorphisms at the apolipoprotein A-1 and C-III loci and hypertriglyceridaemia. A study in a Japanese population

A Japanese group comprising 40 hypertriglyceridaemic and 35 normolipidaemic subjects were genotyped for two intragenic DNA restriction fragment length polymorphisms (RFLPs) at the A-1 and C-III gene loci. An Sst-1 polymorphism is located at the 3' end of the C-III gene and a Msp-1 polymorphism in the third intron of the A-1 gene. The polymorphic restriction sites are 3.8kb apart. The polymorphism with Sst-1 was present at allelic frequencies of 0.67 (S1 allele) and 0.33 (S2 allele), and the polymorphism with Msp-1 was present at allelic frequencies of 0.55 (M1 allele) and 0.45 (M2 allele). The alleles S1, S2, M1, and M2 are in linkage disequilibrium and three haplotypes were identified S1-M1, S1-M2, and S2-M2. Unlike the previously reported association of the S2 allele with hypertriglyceridaemia found in Caucasians there was no difference in the frequency of S2 allele between normolipidaemic and hyperlipidaemic Japanese. However one of the haplotypes S1-M2 was significantly increased in the hypertriglyceridaemic subjects (32% versus 11% P less than 0.025). Thus in Japanese there is an association with genotypes at this locus and hypertriglyceridaemia but with a different haplotype than in Caucasians.

Effects of steroid treatment on release of cardiac myosin light chain II in acute myocardial infarction in dogs

The effect of methylprednisolone sodium succinate (MP) on release of myosin light chain II (LCII) from the myocardium was studied in experimental myocardial infarction (MI). Acute MI was produced in conscious, closed-chest dogs by ligating the left anterior descending coronary artery beyond the first diagonal branch. MP, 30 mg/kg, was administered intravenously just before and 24 hours after MI. After MI, LCII levels in the serum were determined serially up to 240 hours. MI size was determined histologically 10 days after MI. In the MP group, LCII levels in the serum within 72 hours were lower than in the control, and cumulative LCII release for 3 days decreased from 530 +/- 159 to 310 +/- 101 ng/ml (mean +/- standard deviation) (p less than 0.001). However, the peak LCII level appeared later (control vs MP, 63 +/- 27 vs 122 +/- 25 hours, p less than 0.001), and the peak LCII level and cumulative LCII release for 10 days were not decreased by MP treatment. MI size also was not reduced by MP (11.0 +/- 4.4% vs 11.8% +/- 4.5% of the left ventricle, difference not significant). Since the rate of disappearance of LCII is rapid and was not affected by MP, these results suggest that MP treatment early after acute MI delays breakdown of myosin filaments, but cannot prevent it.

Vasopressin as a possible contributor to hypertension

The role of vasopressin as a pressor agent to the hypertensive process was examined. Vasopressin plays a major role in the pathogenesis of DOCA-salt hypertension, since the elevation of blood pressure was not substantial in the rats with lithium-treated diabetes insipidus after DOCA-salt treatment. Administration of DDAVP which has antidiuretic action but minimal vasopressor effect failed to increase blood pressure to the levels observed after administration of AVP. Furthermore, the pressor action of vasopressin appears to be important in the development of this model of hypertension, since the enhanced pressor responsiveness to the hormone was observed in the initial stage of hypertension. Increased secretion of vasopressin from neurohypophysis also promotes the function of the hormone as a pathogenetic factor in hypertension. An unproportional release of vasopressin compared to plasma osmolality may be induced by the absence of an adjusting control of angiotensin II forming and receptor binding capacity for sodium balance in the brain. However, the role of vasopressin remains to be determined in human essential hypertension.

Evaluation of methods for estimating infarct size by myosin LC2: comparison with cardiac enzymes

The relationship between histologically determined infarct size and release or peak levels of circulating cardiac enzymes and myosin light chain 2 (LC2) was studied. Myocardial infarction was produced by ligating the left anterior descending coronary artery in 18 conscious closed-chest dogs. Creatine phosphokinase (CPK), cytosolic and mitochondrial isozymes of aspartate transaminase (sAST and mAST) in the plasma, and LC2 in the serum were measured serially until 10 days after infarction, when infarct size was determined histologically [range 4.0-38.8% of the left ventricular weight (%LV)]. Infarct size correlated most closely with LC2 release (r = 0.82, P less than 0.001) and less closely with peak sAST (r = 0.59, P less than 0.01), peak mAST (r = 0.49, P less than 0.05), peak CPK (r = 0.22), and CPK release (r = 0.14). The correlation between infarct size and CPK release was improved by limiting the analysis to the dogs with infarct size of less than 20% LV (n = 11, r = 0.53, P less than 0.1). Because, among cardiac enzymes and LC2, CPK activity decayed most rapidly in the lymph fluid when incubated in vitro, degeneration of CPK in the lymph stream may contribute to the nonlinear relationship between infarct size and CPK release.