Hereditary deficiency of lactate dehydrogenase H-subunit

We report herein the fifth family of hereditary deficiency of lactate dehydrogenase (LDH) H-subunit with an autosomal recessive inheritance including two cases of complete deficiency. Their LDH activities were low both in the serum and in the red blood cells (RBC). Electrophoretic analysis revealed that the patients with the complete deficiency had only the LDH5 isozyme. The complete deficiency was associated with marked elevation of fructose-1, 6-diphosphate (FDP) and dihydroxyacetonephosphate (DHAP) and a less marked rise in glyceraldehyde-3-phosphate (GA3P) among glycolytic intermediates in the RBC. Furthermore, hemolysis was observed in the present cases, but this finding was not included in the other reports.

Interspecies relationships among ADP-ribosylation factors (ARFs): evidence of evolutionary pressure to maintain individual identities

ADP-ribosylation factors (ARFs) are approximately 20-kDa guanine nucleotide-binding proteins that are allosteric activators of the NAD:arginine ADP-ribosyltransferase activity of cholera toxin and appear to play a role in intracellular vesicular trafficking. Although the physiological roles of these proteins have not been defined, it has been presumed that each has a specific intracellular function. To obtain genetic evidence that each ARF is under evolutionary pressure to maintain its structure, and presumably function, rat ARF cDNA clones were isolated and their nucleotide and deduced amino acid sequences were compared to those of other mammalian ARFs. Deduced amino acid sequences for rat ARFs 1, 2, 3, 5 and 6 were identical to those of the known cognate human and bovine ARFs; rat ARF4 was 96% identical to human ARF4. Nucleotide sequences of both the untranslated as well as the coding regions were highly conserved. These results indicate that the ARF proteins are, as a family, extraordinarily well conserved across mammalian species. The unusually high degree of conservation of the untranslated regions is consistent with these regions having important regulatory roles and that individual ARFs contain structurally unique elements required for specific functions.

Characterization of CP-122,721; a nonpeptide antagonist of the neurokinin NK1 receptor

CP-122,721 [(+)-(2S,3S)-3-(2-methoxy-5-trifluoromethoxybenzyl)amino-2 -phenylpiperidine] interacts with high affinity (pIC50 = 9.8) at the human NK1 receptor expressed in IM-9 cells. In the presence of CP-122,721, there was a reduction in Bmax of [125I]BH-SP binding with no change in affinity suggesting that CP-122,721 does not interact with the NK1 receptor in competitive manner. In an in vitro functional assay. CP-122,721 blocked SP-induced excitation of locus ceruleus cells in guinea pig brain slices with a IC50 value of 7 nM. In vivo, CP-122,721 potently blocked plasma extravasation in guinea pig lung elicited by aerosolized capsaicin (1 mM) with an ID50 = 0.01 mg/kg, p.o. Orally administered CP-122,721 antagonized Sar9, Met (O2)11-SP-induced locomotor activity in guinea pigs with an ID50 = 0.2 mg/kg suggesting good entry into the central nervous system. In addition, consistent with insurmountable blockade observed in vitro, CP-122,721 (0.01, 0.03 0.3 mg/kg, p.o.) produced a rightward shift in the dose response curve for SP-induced hypotension in the awake dog that was accompanied by a decrease in the maximal response. Thus, in vitro and in vivo CP-122,721 appears to behave functionally as a non-competitive antagonist producing an insurmountable blockade of the actions of SP.

Differences in hemostasis among sclerosing agents in endoscopic injection sclerotherapy

Endoscopic injection sclerotherapy is useful in stopping bleeding from esophageal varices. We compared the in vivo effects of sclerosants on thrombogenesis, hemostasis, and endothelial injury. We injected aethoxysclerol (AS) of ethanolamine oleate (EO) into the small veins of the rat intestine. The maximum thrombogenic index with AS was 30.7 and with EO was 9.2. The venous flow stopped sooner with EO than with AS. The thrombi caused by EO were mixed with red blood cells. Heparin pretreatment decreased the thrombogenic index with AS by 96.7%, but not that with EO. The area of the fluorescein-albumin conjugate that permeated from veins with AS was larger than that with EO. The fluorescent intensity with AS was lower than that with EO. We thus conclude that: (1) the size of thrombi is not necessarily proportional to the hemostatic efficacy; (2) change in a patient's coagulation may affect the potential of sclerosants; (3) the excellent hemostatic efficacy of EO is based on localized injury to the endothelium and the involvement of red blood cells aggregation; and (4) in vivo microscopy is useful in determining the rational selection of sclerosants.

Enhancing effect of the liver extract and flavin adenin dinucleotide mixture on anti-viral efficacy of interferon in patients with chronic hepatitis C

A combined preparation of liver extract and flavin adenin dinucleotide (FAD) (Adelavin) has been widely used in patients with chronic liver diseases in Japan. One milliliter of this agent contains 15 microliters of phenol-soluble phase of liver nucleic acid fraction and 10 mg of FAD. To examine the advantages of using this preparation in the elimination of hepatitis C virus (HCV) from patients with chronic hepatitis (CH)-C receiving interferon (IFN), 2 ml of this preparation was intravenously (n = 9) or intramuscularly (n = 8) administered daily for 5 days before 6 million units of IFN-alpha was intramuscularly injected once. Before and 48 hours after the injection of IFN, serum ALT, 2'5'-oligoadenylate synthetase (2'5-AS) activity, and HCV RNA levels were measured. The daily administration of this preparation alone for 5 days did not significantly change serum ALT, 2'5-AS activities, and HCV RNA levels. The 2'5-AS activities were significantly increased by IFN after the intravenous injection of this preparation (p < 0.01), while an injection of IFN alone of this dose did not change its activities (n = 10). HCV RNA levels were significantly decreased by IFN only after the administration of the preparation (intramuscular, p < 0.01; intravenous, p < 0.01). The effect of intravenous injection of this preparation was also elicited in patients with HCV genotype II and with HCV more than 10(5) copies/ml. These results suggest that this preparation may enhance the 2'5-AS production by IFN as a result of the increase in mitochondrial adenosin triphosphate production and may be a potent agent to enhance the anti-viral efficacy of IFN in patients with CH-C.

Role of endothelin-1 in repeated electrical stimulation-induced microcirculatory disturbance and mucosal damage in rat stomach

The aim of the present study was to clarify the involvement of endogenous endothelin in the pathogenesis of gastric mucosal damage. The rat stomach was exposed and repeated electrical stimulation (RES) was applied to the small arterial wall close to the lesser curvature. Significant mucosal haemorrhagic lesions (ulcer and erosion) were noted within 30 min after RES. Intravital microscopic observations revealed that an arteriolar constriction occurred in the submucosal layer of the rat stomach approximately 5 min after the completion of RES. Following the arteriolar constriction, the mucosal blood flow of the rat stomach, which was monitored by using a laser Doppler velocimeter, decreased to approximately 30% of the control value. The plasma immunoreactive endothelin-1 level in the regional blood of the stomach was significantly increased immediately after RES preceding the decrease in mucosal blood flow. Immunohistochemical studies revealed that endothelin-1 and big-endothelin-1 were detectable in the arteriolar endothelium around the muscularis mucosa, supporting the involvement of endothelin-1 in RES-induced mucosal ischaemia. In addition, BQ-123, a specific antagonist of the endothelin A (ETA) receptor, attenuated the reduction of blood flow and the development of haemorrhagic lesions observed in gastric mucosa subjected to RES. The results of the present study suggest that an excessive production of endothelin-1 in the arteriolar endothelium leads to microvascular derangements accompanied by haemorrhagic alterations of the gastric mucosa.

Assessment of histological features and outcome of interferon therapy in chronic hepatitis C

The correlation between the histological features of liver biopsy specimens before interferon (IFN) treatment and the clinical effect of IFN administration on chronic hepatitis C was investigated. A study of the relation between several histological features that were graded in 60 liver biopsy specimens from chronic hepatitis C patients before IFN treatment disclosed that the grade of portal fibrosis was positively correlated with the grade of other inflammatory features, including piecemeal necrosis and portal and lobular inflammation. The degree of portal fibrosis adversely affected the rate of normalization of ALT levels in chronic hepatitis C during and after IFN treatment. We reexamined 36 liver biopsy specimens that showed a moderate degree of portal fibrosis, and found that the degree of piecemeal necrosis was inversely correlated with the extent of lymphoid follicle formation in the portal tracts. During IFN therapy, the group of chronic hepatitis C patients who showed marked piecemeal necrosis and less lymphoid follicle formation in the liver specimens had a poor response to IFN treatment, whereas another group that showed marked lymphoid follicle formation and little piecemeal necrosis in the liver specimens had a good response to IFN. These relationships gradually disappeared after the completion of IFN treatment.

Enhanced levels of chemiluminescence and platelet activating factor in urease-positive gastric ulcers

Helicobacter pylori are believed to play an important role in the formation of gastric ulcer in a syndrome characterized by a high urease activity. On the other hand, the production of oxygen radicals and platelet activating factor (PAF) is enhanced in gastric ulcers. The present study is designed to investigate the relationship between the different aspects of gastric mucosal injury, urease activity, oxygen radical production, and PAF content in gastric specimens. Biopsy specimens taken from 35 gastric ulcer patients were studied. Urease activity was detected by a rapid urease test (CLO). Oxygen radical production was measured as a value of luminol-dependent chemiluminescence (ChL) and PAF content was determined by radioimmunoassay in the biopsy samples. The CLO-positive rate was significantly higher in the gastric ulcer group in comparison with that in controls. ChL values and PAF content were significantly increased in gastric ulcers, especially in CLO-positive specimens. The CLO-positive rate, ChL values, and PAF content were also found to be increased at a distant site beyond the ulcer lesions. During the course of macroscopic ulcer healing of CLO-positive cases, the CLO positive level and the ChL values were not significantly decreased, although PAF content was significantly lower. Enhanced oxygen radical and PAF production were observed not only in the ulcer region but also at a distant site from the ulcer in the urease-positive gastric mucosa. The persistent enhancement of ChL values during the healing stage of urease-positive gastric ulcers suggests its involvement in the recurrence of gastric ulcers.

Humanization of an anti-human IL-6 mouse monoclonal antibody glycosylated in its heavy chain variable region

Interleukin-6 (IL-6) inhibitors are good potential therapeutic agents in human patients, and anti-IL-6 antibodies are among the best candidates. Here, we have successfully humanized mouse monoclonal antibody SK2, which specifically binds to IL-6 and strongly inhibits IL-6 functions. Since this antibody possesses N-linked carbohydrates on Asn-30 of VH region, which seems to be very close to an antigen-binding site, influence of these carbohydrates on antigen-binding was investigated. A biosensor study showed that the mouse SK2 Fab and its deglycosylated fragments had almost equal Kd (Kon/Koff), 26.8 nM (1.05 x 10(6)/2.81 x 10(-2)) and 24.7 nM (1.28 x 10(6)/3.15 x 10(-2)), respectively. Furthermore, a mutant chimeric SK2 antibody, in which the N-glycosylation site was removed from the VH region, showed a Kd of 11 nM, almost similar to that of the original chimeric SK2 antibody, determined by Scatchard analysis with 125I-IL-6. These data indicate the carbohydrates of mouse SK2 VH region do not significantly influence antigen-binding activity. In the next step, two versions of each humanized SK2 VL and VH regions were carefully designed based on the amino acid sequences of human REI and DAW, respectively. Only one alteration, Tyr to Phe, was made at position 71 in the two light chains, according to the canonical residue for LI. A N-glycosylation site was introduced on the two heavy chains, by changing Ser to Asn at position 30. All four combinations of humanized light and heavy chains could bind to IL-6 as well as the chimeric SK2 antibody. The light chain first version, however, could not efficiently inhibit IL-6 binding to its receptor, indicating the importance of the LI loop conformation for the inhibitory activity of SK2 antibody. In contrast, both versions of the heavy chains were comparable, in yielding good humanized SK2 antibodies, suggesting that the glycosylation of the SK2 VH region has no influence in recreating a functional antigen-binding site in this humanization.

Activation of Clostridium botulinum C3 exoenzyme-catalyzed ADP-ribosylation of RhoA by K+ in a Mg2+ -dependent manner

The effect of KCl on ADP-ribosylation of the recombinant RhoA protein catalyzed by the Clostridium botulinum C3 enzyme was studied. When the recombinant glutathione S-transferase-RhoA fusion protein (GST-RhoA) was incubated with C3 and [adenylate-32P]NAD, incorporation of radioactivity into the recombinant RhoA increased in the presence of KCl. The increase in ADP-ribose incorporation into RhoA due to KCl appeared in the presence of MgCl2 and was abolished by EDTA. C3 was stabilized by KCl, but the stabilization was also seen with BSA. The KCl-induced increase in the ADP-ribosylation was observed even in the presence of BSA during the modification reaction, thus the effect of KCl was not due to the stabilization of C3. While the initial rate of the reaction was increased by KCl, maximum incorporation of ADP-ribose per GST-RhoA molecule did not increase in the presence of KCl. Kinetic analysis revealed that KCl increased Vmax but did not alter Km for either NAD or RhoA. The NAD glycohydrolase activity of C3 was also increased by KCl. These results indicate that KCl directly activates the C3 enzyme.

[Cephalad movement of the carina due to CD (Cotrel-Dubousset) instrumentation for idiopathic scoliosis]

Recently we experienced a case of tracheal tube obstruction due to the upward displacement of carina during CD (Cotrel-Dubousset) instrumentation for idiopathic scoliosis. Therefore, we hypothesized that CD instrumentation may affect the position of the carina as a result of correction of chest deformity, and studied the displacement of carina before and after CD instrumentation on chest X-ray in 12 patients with scoliosis. The length between the bottom of the 6th cervical vertebral body and the carina was measured by using chest X-ray before and after the correction. In all patients studied, cephalad movement of the carina was observed, and it was more than 1.00 cm in 5 patients. The maximal movement of the carina was 1.59 cm. The tracheal length after the correction was significantly shorter than before (P < 0.01). These results suggest that the carina may be displaced upwards due to the correction by the CD instrumentation, and that such induced displacement may affect the tracheal tube position and obstruct the tube during the operation.

Plasticity of myofibroblasts appearing in granulation tissues after acetic acid treatment. Effect of bFGF

To clarify the origin of the myofibroblasts appearing in the healing process of the acetic acid-induced ulcer and effect of basic fibroblast growth factor (bFGF) on these myofibroblasts, we conducted an immunohistochemical study using antibody to intermediate filaments, desmin and vimentin. The binding sites of bFGF on the regenerative tissues were also studied by the radioautographic study of soluble compounds. As a result, the binding sites of bFGF were accumulated on the fibroblasts and myofibroblasts as well as on endothelial cells. The effect of CS23, acid-stable human recombinant bFGF was shown on distribution of myofibroblasts and regeneration of the microvascular system in the mucosal and submucosal layers.

Bile acid-induced depolarization of mitochondrial membrane potential preceding cell injury in cultured gastric mucosal cells

Changes in energy metabolism elicited by sodium taurocholate and their relation to cell viability were determined in gastric mucosal cells. Cultured mucosal cells were labelled with rhodamine-123, a mitochondrial energization-sensitive fluorescence probe, or by propidium iodide, a fluorochrome which labels the nuclei of non-viable cells. The cells were observed under a fluorescence microscope with a laser scanning confocal imaging system. After the addition of sodium taurocholate at concentrations > 5 mol/L, mucosal cells showed a rapid and significant decrease in rhodamine-123 fluorescence. A decrease to 40% of the pretreated values at 30 min was seen with a concentration of sodium taurocholate of 7.5mmol/L. A marked increase in the percentage of propidium iodide-positive cells was noted when the concentration of sodium taurocholate exceeded 5mmol/L. However, the extent of the decrease in rhodamine-123 fluorescence was always greater than the increase in the percentage of propidium iodide-positive cells, suggesting that most of these gastric mucosal cells remained viable. It is therefore suggested that the decrease in rhodamine-123 fluorescence is largely due to the disturbed oxidative phosphorylation of mitochondria. Pretreatment of gastric mucosal cells with low concentrations of ethanol resulted in a significant cytoprotective effect against sodium taurocholate injury with significant prevention of a decrease in rhodamine-123 fluorescence. It is concluded that sodium taurocholate induces a depolarization of the mitochondrial membrane potential preceding cell injury and that the cytoprotective effect of ethanol relates to its attenuation of the uncoupling effect.

Detection of arginine-ADP-ribosylated protein using recombinant ADP-ribosylarginine hydrolase

We made use of ADP-ribosylarginine hydrolase to detect arginine-ADP- ribosylated proteins. The hydrolase was expressed in Escherichia coli as a protein fused with glutathione S-transferase (GST). The fusion protein GST-ADP-ribosylarginine hydrolase catalyzed the hydrolysis of alpha-ADP-ribosylarginine to produce ADP-ribose and arginine. Casein ADP-ribosylated with [32P]NAD and chicken heterophil arginine-specific ADP-ribosyltransferase served as a substrate for the recombinant ADP-ribosylarginine hydrolase and the released ADP-ribose was determined. Protein ADP-ribosylated by cholera toxin could serve as substrate of the hydrolase but protein ADP-ribosylated by pertussis toxin, diphtheria toxin, or C(3) enzyme of Clostridium botulinum could not. The hydrolase did not release the radioactivity incorporated into isolated rat liver nuclei incubated with [(32)P]NAD or in bovine brain cytosol incubated with [(32)P]ADP-ribose. In homogenate of mouse heart which contained arginine-specific ADP-ribosyltransferase, labeling of a 55-kDa protein by incubation with [(32)P]NAD was removed by ADP-ribosylarginine hydrolase treatment; hence, the specific hydrolysis of ADP-ribose-arginine bond by GST-ADP-ribosylarginine hydrolase can be used to detect the arginine-ADP-ribosylated proteins in crude preparations. Arginine--ADP-ribosylated proteins in crude preparations. Arginine-ADP-ribosylated proteins in mouse spleen lymphocytes were identified using this method.

Intravital demonstration of sequential migration process of lymphocyte subpopulations in rat Peyer's patches

BACKGROUND & AIMS

Although recirculation of lymphocytes through Peyer's patches is important for specific immune defense, the intraorgan migration of lymphocyte subpopulations has not been clearly understood. The aim of this study was to compare the spatial distributions of labeled lymphocytes among various subpopulations in rat Peyer's patches.

METHODS

Lymphocytes collected from intestinal lymph were separated into CD4+, CD8+, and T and B cells, labeled with a fluorochrome carboxyfluorescein diacetate succinimidyl ester, and injected into the jugular vein. Peyer's patches of recipient rats were observed by intravital fluorescence microscopy.

RESULTS

No significant difference was found in the percentage of lymphocytes in transit or in the rolling velocity among different subpopulations. Lymphocytes sticking to the venules increased in number at 10-20 minutes, with preferential adherence of CD4+ cells to venules of 25-50 microns and preferential adherence of B cells to the venules of a wider size range. After 30 minutes, extravasated lymphocytes moved into the interstitium. B cells migrated from venules more quickly than CD4+ cells. CD8+ cells showed an intermediate pattern between CD4+ and B cells in sticking and migratory behaviors. Subsequently, CD4+ and CD8 cells preferentially appeared in parafollicular microlymphatics.

CONCLUSIONS

Significant differences were observed among lymphocyte subpopulations in terms of spatial distribution of lymphocytes sticking to venules, migration into the interstitium, and their lymphatic transport.

Effects of aluminum adjuvant on systemic reactions of lipopolysaccharides in swine

In vivo effects of aluminum adjuvant on systemic reaction of bacterial lipopolysaccharide (LPS) in piglets were investigated. Intramuscular injection of 0.1 mg kg-1 of LPS added to aluminum hydroxide gel (LPS(+)AL) mitigated the leukopenia, trembling and serum levels of TNF-alpha and cortisol compared with the injection of LPS suspended in LPS-free saline (LPS(+)SALINE). The serum endotoxin levels were reduced remarkably but relatively long-lasting in the LPS(+)AL. The lethality in mice injected with LPS added to aluminum hydroxide gel was significantly reduced. Likewise, the Limulus activity of a test LPS was reduced by the addition of aluminum hydroxide gel or aluminum chloride.

Effects of ventilation and pleural effusion on measurements of airway thermal volume and blood flow in dog lungs

We studied the effects of ventilation and pleural effusion on measurements of airway thermal volume (ATV) and pulmonary blood flow (PBF) by using the airway gas thermometry method of V. B. Serikov, M. S. Rumm, K. Kambara, M. I. Bootomo, A. R. Osmack, and N. C. Staub (J. Appl. Physiol. 72: 944-953, 1992) in 39 anesthetized dogs with or without lung edema or pleural effusion. To examine the differential effects of increased-pressure and increased-permeability lung edema on accuracy and sensitivity of ATV and PBF, two models of lung edema were induced by intravenous infusion of a Dextran 70 solution and alloxan monohydrate, respectively. Dogs were hyperventilated for 3 min by using a wide range of minute ventilation (VE) to produce two steady-state conditions of airway temperature. Higher levels of VE increased an estimated amount of ATV. The ATV produced by hyperventilation at VE values of 559, 158, and 72 ml.min-1.kg-1 was consistent with the gravimetric total lung mass, the blood-free wet lung weight, and the extravascular lung water volume, respectively. The coefficient of lung thermal conductivity, a practical index of the rate of heat conduction through tissue from lung vessels, was related to the ratio of the decrease in expired air temperature to VE, and estimated PBF was consistent with the thermodilution cardiac output. Pleural effusion had little effect on measurements of ATV and PBF. However, ATV and PBF showed increased variation in dogs with dextran-induced lung edema.

Oxidative stress in gastric mucosal injury: role of platelet-activating factor-activated granulocytes

Temporal and spatial changes due to oxidative stress in the rat gastric mucosa were visualized and quantified during the process of mucosal hemorrhagic change. The fluorescence associated with dichlorofluorescein (DCF), a hydroperoxide-sensitive fluorochrome, increased 30 min after repeated electrical stimuli to the gastric artery. The increase in the fluorescence was enhanced in the area between two adjacent collecting venules. The content of platelet-activating factor (PAF), the activity of myeloperoxidase (MPO) in the gastric mucosa, the area of mucosal lesions, and the luminol-dependent chemiluminescence activity in zymosan-treated blood samples, obtained from the gastric vein, were measured and found to increase significantly 30 min after the stimuli. The intravenous injection of CV-6209, a PAF antagonist, 5 min prior to the stimuli significantly inhibited the DCF activation, the increases in PAF level and MPO activity, the mucosal hemorrhagic change, and the elevation in chemiluminescence activity. In addition, continuous infusion of superoxide dismutase also inhibited all these changes, except for chemiluminescence activity. These results suggest that oxygen radicals derived from PAF-activated granulocytes induce oxidative stress, and that oxidative changes are actually implicated in the pathogenesis of gastric mucosal injury.

A newly identified GPI-anchored arginine-specific ADP-ribosyltransferase activity in chicken spleen

Arginine-specific ADP-ribosyltransferase activity was detected in chicken spleen membrane fraction and the activity was extracted by phosphatidylinositol-specific phospholipase C but not by 1 M NaCl or 1% Triton X-100. The transferase activity extracted from the spleen membrane was thiol-independent and was not inhibited by 200 mM NaCl. Zymographic analysis of the transferase, under non-reducing conditions, showed two forms of active bands corresponding to a molecular mass of 46 and 42 kDa. Thus, the presence of this novel arginine-specific ADP-ribosyltransferase, anchored to the membrane through glycosylphosphatidylinositol and different from previously cloned chicken transferases, AT1 and AT2, is being given further attention.

Helicobacter pylori urease inhibition by rabeprazole, a proton pump inhibitor

We investigated the inhibitory effects of four gastric proton pump inhibitors (PPIs): rabeprazole, a novel benzimidazole PPI, omeprazole, lansoprazole and AG-2000, on the urease activity of Helicobacter pylori (H. pylori). Their 50% inhibitory concentrations (I50s) were found to be 0.29, 5.4, 9.3 and 0.3 microM respectively. Rabeprazole and omeprazole were also potent inhibitors of Jack bean and Proteus mirabilis cellular ureases. The thioether derivative of rabeprazole, one of its metabolites, had no inhibitory effect on H. pylori urease, despite being reported as a more potent inhibitor of H. pylori growth than rabeprazole. The inhibitory effect of rabeprazole was prevented completely and reversed considerably by the addition of sulfhydryl compounds, such as beta-mercaptoethanol, glutathione and dithiothreitol. Moreover, the addition of beta-mercaptoethanol recovered the urease activity inhibited by rabeprazole. From these results, we expected that rabeprazole inhibited H. pylori urease activity by forming disulfide bonds between it and the active site of the enzyme.

Effect of basic fibroblast growth factor on reinnervation of gastric microvessels. Possible relevance to ulcer recurrence

Basic fibroblast growth factor (bFGF) has well-established angiogenic and ulcer healing actions. bFGF has also been found to induce neural regeneration in the central nervous system. Thus, the present study was undertaken to clarify the effect of basic fibroblast growth factor on the regeneration of autonomic nerves in the granulation tissues following the induction of experimental gastric ulcer induced by acetic acid in rats. Rats were divided into control, acetic acid alone, and acetic acid plus acid-stable human recombinant basic fibroblast growth factor (CS23, 1 microgram/100 g body wt., every 12 hr for three days, or one or two weeks, through oral gastric intubation) groups. As a result, few autonomic nerves were recognized surrounding the newly formed arterioles and venules in the acetic acid alone group. In the CS23-treated group, the cholinergic, calcitonin gene-related peptide and vasoactive intestinal peptide-immunoreactive nerves were clearly recognized near the microvessels, but few adrenergic nerves were seen even after CS23 treatment. From these observations, basic fibroblast growth factor was suggested to promote the reinnervation of the newly formed microvessels.

Conjugated bile salts regulate turnover of rat intestinal brush border membrane hydrolases

The mechanisms whereby the conjugated bile salts regulate the activities of the brush border membrane hydrolases and its physiological significance were investigated in rat small intestine, and comparisons were made with the action of pancreatic protease. Rat brush border membrane proteins were metabolically labeled with [35S]methionine, and isolated brush border membrane was incubated with taurocholate or pancreatic elastase. The activity of solubilized hydrolases was assayed and the molecular forms of the hydrolases were examined by SDS-PAGE. The activity and protein bands of alkaline phosphatase and sucrase-isomaltase were solubilized by taurocholate, while alkaline phosphatase was not solubilized by elastase. Solubilized sucrase-isomaltase molecules were proteolytically degraded by elastase, whereas the intact molecule of sucrase-isomaltase was solubilized by taurocholate. Next the physiological role of bile salts in brush border membrane hydrolase turnover were investigated using metabolic labeling of brush border membrane hydrolase and immunoprecipitation in biliary diversion rats. After three days of biliary diversion, a significant increase in alkaline phosphatase activity was observed. Although synthesis of alkaline phosphatase in biliary diversion rats was similar to that observed in control rats, biliary diversion rats showed 1.5-fold slower turnover of alkaline phosphatase when compared with control rats. These results suggest that conjugated bile salts in the intestinal lumen may cause a rapid turnover of brush border membrane hydrolases, which may be increased by the enhanced enzyme degradation. The mechanisms for the enhanced degradation appeared to be solubilization of hydrolases caused by the detergent activity of bile salts. Therefore, conjugated bile salts may play an important physiological role in the regulation of expression of the protease-resistant enzymes such as alkaline phosphatase.

Wound healing of acetic acid-induced gastric ulcer in rats and the effects of cimetidine and calcitonin, with special reference to prolylhydroxylase and collagenase enzyme activity

The healing of acetic acid-induced gastric ulcer in rats and the effects of cimetidine and calcitonin were investigated with reference to the enzyme activity of both prolylhydroxylase and collagenase as related to histological findings. The rats were observed by endoscopy on the 3rd day after the subserosal injection of acetic acid; rats with ulcers were divided into three groups: non-treated, and cimetidine- and calcitonin-treated. The latter two groups were treated for 7 days. Prolylhydroxylase activity in active ulcers in the non-treated group was slightly higher on the 3rd day and significantly higher on the 10th day than the activity in control rats that had received subserosal injections of physiological saline solution on the respective days. In non-treated rats, the healed ulcer on the 10th day showed lower prolylhydroxylase activity than that in the active ulcer on the same day. Cimetidine did not affect prolylhydroxylase activity, but, with calcitonin, there was higher prolylhydroxylase activity in the healed than in the active ulcer, although the difference was not significant. Interstitial collagenase showed the highest activity on the 3rd day and decreased on the 10th day in non-treated rats. Collagenase activity was higher in the cimetidine-treated group, than that in the non-treated group, and numerous peroxidase-positive granulocytes were seen in the mucosa and submucosa. Calcitonin did not affect collagenase activity. The participation of both enzymes is indispensable in the healing process and the effects of anti-ulcer agents on these enzymes must be considered.

Spatial heterogeneity of mucosal blood flow during ischemia-reperfusion injury of rat stomach investigated by laser Doppler perfusion imaging

Spatial alterations in blood flow during the development of mucosal injury induced by ischemia-reperfusion in rats were determined with a two-dimensional laser Doppler tissue perfusion imager. The rats were anesthetized with pentobarbital, and the stomach was exteriorized on a stage; the mucosa was then sequentially scanned. The mucosa was constantly superfused with 0.1 N HCl in physiological saline. Systemic arterial pressure was continuously monitored and blood was stepwisely withdrawn from the femoral artery by 20-mmHg stage and then maintained at 20 mmHg for 20 min. The shed blood was reinfused and the stomach was removed 30 min later. Under control conditions, the average perfusion of the forestomach was usually greater than that in the glandular stomach. When systemic blood pressure was stepwisely decreased, the extent of decrease in the mucosal blood perfusion unit was always greater than that in systemic blood pressure, but mucosal perfusion appeared to be uniformly decreased throughout the stomach. Ten min after reperfusion, a hypoperfused area began to appear in the corpus near the greater curvature, and this area subsequently increased. The area of ulcer formation corresponded with the hypoperfused area in the gastric mucosa 30 min after reperfusion. Pretreatment with CV-6209, a platelet-activating factor antagonist, significantly attenuated the hypoperfusion induced by reperfusion and also prevented gastric mucosal damage. Our results suggest that hypoperfusion in the mucosal microcirculation is indeed an important factor contributing to the localized occurrence of gastric mucosal lesions and that the laser Doppler perfusion imager is useful for the detection of local hypoperfused areas in the gastric mucosa.

Interleukin 7 is produced by human intestinal epithelial cells and regulates the proliferation of intestinal mucosal lymphocytes

The interaction of mucosal lymphocytes and intestinal epithelial cells is thought to be important in regulating immune response in the intestinal mucosa, but conclusive evidence is limited. Here we demonstrate the expression of IL-7 mRNA in human intestinal mucosa by combined reverse transcription PCR and Southern blot hybridization. Immunohistochemistry and in situ hybridization confirm the presence of IL-7 in intestinal epithelial cells, especially in epithelial goblet cells. Moreover, IL-7 receptor expression in mucosal lymphocytes is demonstrated by immunohistochemistry and in situ hybridization, as well as by Southern blot and flow cytometric analysis of freshly isolated lamina propria lymphocytes. In contrast, IL-7 receptor could not be detected in the cell surface of freshly isolated PBLs. The functional activity of IL-7 receptor is demonstrated by the utility of recombinant IL-7 to stimulate the growth of lamina propria lymphocytes, and conversely inhibit CD3-dependent proliferation of these cells. In contrast, IL-7 caused no significant increase in DNA synthesis and cell numbers when added to PBLs. These findings suggest that human intestinal epithelial cells and epithelial goblet cells produce IL-7, and locally produced IL-7 may serve as a potent regulatory factor for intestinal mucosal lymphocytes.

Humanization of mouse ONS-M21 antibody with the aid of hybrid variable regions

Mouse monoclonal antibody, ONS-M21, directed against human medulloblastoma cells, has been humanized by complementarity determining region (CDR) grafting. A humanized ONS-M21 VH region, comparable to the original mouse ONS-M21 VH region, was easily constructed based on framework regions (FRs) 1, 2 and 3 from human EU antibody and on FR4 from human ND antibody. Five alterations in the FRs were made at amino acids 27, 28, 29, 30 and 94 which are all part of the canonical structure for CDR1 (H1). The humanized ONS-M21 VL regions were constructed based on the FRs from human REI antibody. We first identified five amino acid residues in the FRs at positions 20, 21, 71, 73 and 87 as having a possible adverse influences on antigen binding. None of the versions with a variety of combinations at these five positions showed any bindings to antigen. In order to identify the mouse residues that must be retained in the human FRs, hybrid VL regions were constructed by joining the mouse ONS-M21 VL region and the first humanized version within CDR2. The hybrid VL regions revealed that residues in FR1 and/or FR2 were critical in creating a functional antigen binding site. Redesigning several versions with alterations in FR1 and FR2 revealed that the Pro-46 residue was the only critical residue for creating an antigen binding site. This approach should be helpful in identifying key residues in difficult cases of antibody humanization.

Sialidase of swine influenza A viruses: variation of the recognition specificities for sialyl linkages and for the molecular species of sialic acid with the year of isolation

The sialidase of swine influenza A viruses of N1 and N2 subtypes, isolated from 1930 to 1992, was studied for substrate specificity with ganglio-series, lacto-series type II and GM3 gangliosides containing Neu5Ac alpha 2-3Gal, Neu5Gc alpha 2-3Gal and Neu5Ac alpha 2-6Gal linkages. All viral sialidases tested showed that the activity for hydrolysing substrates with Neu5Ac alpha 2-3Gal was higher than the activities with Neu5Gc alpha 2-3Gal and Neu5Ac alpha 2-6Gal linkages. When GM1b, GM3 and sialylparagloboside were used as substrates, the earliest strain (A/Wisconsin/15/30 H1N1, isolated in 1930) showed the activity ratio of Neu5Ac alpha 2-6Gal to Neu5Ac alpha 2-3Gal to be 0.13:0.2, and the ratio Neu5Gc alpha 2-3Gal/Neu5Ac alpha 2-3Gal to be 0.19:0.37, while those strains isolated from 1978 to 1992 exhibited ratios of 0.29:0.58 for Neu5Ac alpha 2-6Gal/Neu5Ac alpha 2-3Gal and 0.51:0.76 for Neu5Gc alpha 2-3Gal/Neu5Ac alpha 2-3Gal. The above results indicate that the substrate specificities of sialidases from swine influenza A viruses towards sialyl linkages and the molecular species of sialic acid are related to the year of isolation, i.e. strains isolated after 1978 exhibited higher activity towards Neu5Ac alpha 2-6Gal and Neu5Gc alpha 2-3Gal linkages when compared with strains isolated in an earlier year, 1930.

Antibody-dependent cell-mediated cytotoxicity against cell lines generated by liver-specific idiotype-bearing antibody

We produced a murine monoclonal antibody (mAb), designated H2-mAb, against a fractionated soluble phase of human liver homogenate which antibody reacted with human liver cells. A human antibody possessing the same idiotype as the H2-mAb, designated LSIA (liver-specific idiotype-bearing antibody), can be measured by a sandwich enzyme-linked immunosorbent assay, using the anti-H2 idiotype antibody. The serum level of LSIA in patients with histologically proven chronic hepatitis (CH) was significantly higher than that in healthy subjects and it was also higher than that in subjects with other diseases, including systemic lupus erythematosus. In a comparison between patients with CH type B and those with CH type C, there was no significant difference in serum levels of LSIA. It was possible to purify LSIA from the sera of patients with CH. The purified LSIA bound to the human cell lines Chang and HCC-M, derived from liver cells and a hepatoma respectively, but not to HeLa cells, a uterine carcinoma derivative. The reactivity of this mAb to HCC-M was weaker than that to Change. Moreover, the presence of LSIA caused an antibody-dependent cell-mediated cytotoxic challenge against Change cells in vitro.

Establishment of a novel myeloma cell line KPMM2 carrying t(3;14)(q21;q32), which proliferates specifically in response to interleukin-6 through an autocrine mechanism

We established a new human myeloma cell line, KPMM2, which proliferates specifically in response to IL-6 via an autocrine mechanism. The proliferative response of KPMM2 cells to exogenous IL-6 was significantly stimulated in a dose-dependent manner. The growth was markedly inhibited by an anti-IL-6 mAb and an anti-IL-6 receptor (IL-6R) mAb in a dose-dependent manner. KPMM2 cells expressed IL-6 and IL-6R mRNA by RT-PCR. Flow cytometric analysis showed cell surface expression of IL-6R. IL-6 protein was detected in the culture supernatant by ELISA. IL-11, oncostatin M and leukemia inhibitory factor had no effect on the proliferation of KPMM2 cells although interferon-alpha and interferon-gamma inhibited the growth. Furthermore, KPMM2 cells bore a t(3;14)(q21;q32) translocation and this finding is of potential interest for future studies in the light of the nuclear protein BM28 (CDCL1, for cdc-like 1) mapped on 3q21, which plays an important role in the cell cycle. In this report, we demonstrated completely an IL-6-dependent autocrine growth mechanism in KPMM2 cell line. This cell line may be useful to investigate the pathogenesis of multiple myeloma and to evaluate the therapeutic potential of IL-6 blocking agents in vitro and in vivo.

Formation of bioorganic compounds in planetary atmospheres by cosmic radiation

Simulated planetary atmospheres (mixtures of simple gases) were irradiated with high energy particles to simulate an action of cosmic rays. When a mixture of carbon monoxide, nitrogen and water was irradiated with 2.8-40 MeV protons, a wide variety of bioorganic compounds including amino acids, imidazole, and uracil were identified in the products. The amount of amino acids was proportional to the energy deposit to the system. Various kinds of simulated planetary atmospheres, such as "Titan type" and "Jovian type", were also irradiated with high energy protons, and gave amino acids in the hydrolyzed products. Since cosmic rays are a universal energy source in space, it was suggested that formation of bioorganic compounds in planetary atmospheres is inevitable in the course of cosmic evolution.

Uptake site of lansoprazole, a proton pump inhibitor, in human fundic mucosa: possible relevance with fibroblast and Helicobacter pylori

To clarify the mechanism of the effect of lansoprazole in the healing of human gastric ulcer, the uptake sites of lansoprazole were studied using endoscopically biopsied specimens from the margin of the gastric ulcer. The specimens were incubated in a medium containing 3H-lansoprazole for 5 or 15 min., postfixed with 1% osmic acid and embedded in Epon. The semithin or ultrathin sections were made and radioautographic emulsion films were applied by the wire-loop method. 30 days after the incubation, the sections were developed, fixed and observed by light and electron microscopy. As a result, the uptake sites of lansoprazole were accumulated on the fibroblasts located near the tip portion of the gastric mucosa and on the unmyelinated nerve fibers as well as on the parietal cells. Some of the uptake sites were also observed near the plasma membrane of the bacteria in the gastric lumen. From these observations, lansoprazole uptake sites were not only on the parietal cells but on the fibroblasts and the bacteria, suggesting that the effect of lansoprazole was exerted partly through the influence on the mesenchymal cells and Helicobacter pylori-related organisms.

Relationship between hepatitis C virus subtypes and clinical features of liver disease seen in alcoholics

The influence of hepatitis C virus and its subtypes on the clinical course of liver disease in alcoholics was assessed. Hepatitis C virus infection was confirmed by a reverse transcription and polymerase chain reaction method for the hepatitis C virus NS-5 region in the sera of alcoholics with various stages of histologically proven liver disease. The frequency of hepatitis C virus was significantly higher in alcoholics with chronic hepatitis (73%) than in those with liver fibrosis (18%), alcoholic hepatitis (17%), and fatty liver (0%). Hepatitis C virus subtypes, namely K1 and K2, were determined by dot-blot hybridization analysis of the polymerase chain reaction products with specific probes, and their frequencies were 68% and 32%, respectively. The proportion of patients whose serum transaminase levels returned to normal following 4 weeks of abstinence in hospital was significantly lower in alcoholics with hepatitis C virus viremia (glutamic oxaloacetic transaminase: 53.8%; glutamic pyruvic transaminase: 42.3%) than in those without viremia (glutamic oxaloacetic transaminase: 86.2%, p < 0.01; glutamic pyruvic transaminase: 89.7%, p < 0.01). When alcoholics with the K1 and K2 subtypes of hepatitis C virus were compared, normalization of transaminase levels was less frequent in alcoholics with K1 (glutamic oxaloacetic transaminase: 42.8%; glutamic pyruvic transaminase: 28.6%) than in those with K2 (glutamic oxaloacetic transaminase: 88.9%, p < 0.05; glutamic pyruvic transaminase: 77.8%, P < 0.05). These data indicate that hepatitis C virus infection is associated with a reduced rate of recovery of serum transminase levels following abstinence in subjects with alcoholic liver disease, more so in the K1 subtype than in the K2 subtype.

Assay of arginine-specific adenosine-5'-diphosphate-ribosyltransferase by capillary electrophoresis

Using high-voltage capillary electrophoresis we detected ADP-ribosylarginine, a product of ADP-ribosylation reaction catalyzed by arginine-specific ADP-ribosyltransferase in the presence of NAD and L-arginine. The authentic ADP-ribosylarginine, detected by its ultraviolet absorbance at 254 nm, had a different retention time from NAD or nicotinamide. When the ADP-ribosylation reaction products were analyzed, the peak corresponding to ADP-ribosylarginine increased with incubation time and in an enzyme-dose-dependent manner. The lower limit of detection was 0.3 pmol, a value 100 times lower than that obtained with the reversed-phase high-performance liquid chromatography assay described previously. Using the capillary electrophoresis system, a thiol-independent ADP-ribosyltransferase activity was detected in chicken spleen cell membrane. Since the capillary electrophoresis assay for ADP-ribosylarginine is simpler, faster, and less expensive than the high-performance liquid chromatography assay, determination of arginine-specific ADP-ribosyltransferase activity in animal tissues will be facilitated.

Autoradiographic demonstration of lansoprazole uptake sites in rat antrum and colon

To investigate possible effects of lansoprazole other than its acid suppression through the parietal cell, uptake sites for lansoprazole were studied by autoradiography in rat antral and colon mucosa. Autoradiography was performed using two different methods, i.e., routine fixation and in vitro autoradiography on cryostat sections. Our results showed that the uptake sites for lansoprazole in the gastric antrum were located in the interstitial cells, including unmyelinated nerve fibers, whereas those in the colon mucosa corresponded to epithelial cells and some of the interstitial cells. With electron microscopy, the uptake sites for lansoprazole in the colon epithelial cells were seen exclusively near the apical plasma membrane. On the basis of these findings, lansoprazole may have effects on autonomic nerve and colon epithelial function as well as on acid secretion.

Substance P induces degranulation of mast cells and leukocyte adhesion to venular endothelium

Substance P (SP), one of the established neurotransmitters, evokes an immunoinflammatory response involving leukocyte adhesion to venular endothelium and the degranulation of mast cells. The pathogenetic relationship between these responses, however, remains unresolved. In this study, we propose to examine the changes associated with the activation of mast cells, as well as leukocyte adhesion to venular endothelium by in vivo observation of the rat mesentery. The use of an in vitro assay for intracellular Ca2+ mobilization and the degranulation of mast cells demonstrated the significant upper shift of concentration response to SP (10(-4)-10(-5) M). In vivo experiments on the mesenteric microcirculation also showed that SP induced a significant increase in the number of degranulated mast cells as well as in the number of leukocytes adherent to the venular wall. Tranilast, a mast cell stabilizer, as well as SP antagonist (CP-96,345) significantly attenuated the extent of mast cell degranulation and leukocyte adhesion elicited by SP. Although an immunoneutralization against CD18 by WT-3 significantly attenuated the leukocyte adhesion, it had no influence on the mast cell degranulation after SP superfusion. These separate in vivo observations show that SP induces leukocyte adhesion to the venular endothelium, possibly through the degranulation of mast cells.

Lansoprazole inhibits oxygen-derived free radical production from neutrophils activated by Helicobacter pylori

We studied the influence of lansoprazole on Helicobacter pylori-elicited neutrophil activation, including the oxidative burst and infiltration of gastric mucosa, and confirmed whether radiolabeled lansoprazole is actually detected in gastric neutrophils. The oxidative burst of purified human neutrophils was measured by luminol-dependent chemiluminescence (ChL). [3H]Lansoprazole uptake sites in human gastric mucosa were observed by autoradiography. The magnitude of neutrophil infiltration of gastric mucosa was assessed by tissue myeloperoxidase (MPO) content. ChL assay indicated that oxygen-derived free radical production was increased twofold by adding H. pylori water extract, which was significantly inhibited by lansoprazole (10(-4) M). Gastric biopsy samples were obtained endoscopically from patients with H. pylori-positive gastritis. Autoradiographic examination revealed that the [3H]lansoprazole binding site was present in the cytoplasmic granules of infiltrated neutrophils. Tissue MPO content was significantly decreased after treatment with lansoprazole. These data suggest that lansoprazole binds directly to neutrophils, subsequently inhibiting neutrophil accumulation and release of toxic metabolites.

Hepatic tumors induced by carbon tetrachloride in transgenic mice carrying a human c-H-ras proto-oncogene without mutations

Hepatic tumors were generated in mice by repeated administration of carbon tetrachloride (CCl4). Eight transgenic (Tg) mice carrying a human c-H-ras proto-oncogene (rasH2 line) and 9 non-Tg mice were killed at 20 weeks. Tg mice developed more tumors than did non-Tg littermates. Most tumors were neoplastic nodules, but 1 hepatocellular carcinoma (HCC) was found in a Tg mouse at 20 weeks. Three Tg and 2 non-Tg mice were kept without further administration of CCl4. Two Tg mice died at 30 weeks of HCC with intra-abdominal bleeding, and 1 Tg mouse developed HCC with a mesenteric metastasis at 32 weeks. No HCC was found in 2 non-Tg mice at 32 weeks. Although mutations at codon 12, 13, and 61 of the H-ras gene are often found in murine hepatocarcinogenesis, neither the tumors, including one HCC, nor the normal cells revealed any such mutations. These results showed that the unmutated human c-H-ras gene facilitates malignant transformation of hepatocytes when continuous liver-cell death and regeneration is caused by repeated administration of CCl4.

Cloning and expression of cDNA for arginine-specific ADP-ribosyltransferase from chicken bone marrow cells

Two arginine-specific ADP-ribosyltransferase cDNAs (designated AT1 and AT2) were cloned from chicken bone marrow cells. Each cDNA encodes a different peptide of 312 amino acid residues. Homology of deduced amino acid sequences between AT1 and AT2 was 78.3%. We found all six combined peptide sequences of 222 amino acid residues derived from purified chicken heterophil ADP-ribosyltransferase (Mishima, K., Terashima, M., Obara, S., Yamada, K., Imai, K., and Shimoyama, M. (1991) J. Biochem. (Tokyo) 110, 388-394) in the deduced amino acid sequence of AT1, with two amino acid mismatches. Arginine-specific ADP-ribosyltransferase activity was detected in culture medium of COS 7 cells transiently transfected with AT1 cDNA, while activity from the cells transfected with AT2 cDNA was found in both culture medium and cell lysate. AT1 transferase required 2-mercaptoethanol for the activity. The activity was inhibited in the presence of NaCl while AT2 enzyme was activated by either agent. On zymographic in situ gel analysis, estimated molecular masses of the AT1, AT2 and purified chicken heterophil transferases were 32, 34, and 27.5 kDa, respectively. Northern blot analysis with specific probes to AT1 or AT2 cDNAs revealed about a 1.5-kilobase message in chicken bone marrow cells but no signals were observed in heterophils, spleen, and liver of chicken or human HL-60 cells. Highly conserved regions were observed among the deduced amino acid sequences of AT1, AT2, rabbit skeletal muscle transferase, and rodent T-cell surface antigen RT6s.

Sulfhydryl blocker-induced colitis in the rat: immunological changes in thymus gland and colonic mucosa

The study was designed to examine the changes of thymus in sulfhydryl blocker-induced colitis. We used N-ethylmaleimide (NEM) as sulfhydryl blockers. Fasted male Sprague-Dawley rats were given 3% NEM in 1% methyl cellulose into the colon. N-ethylmaleimide treatment caused severe diarrhoea with bleeding for the first 7 days. At autopsy, adhesions, colon dilatation, and single or multiple erosions and ulcers were observed. Time-course studies revealed that the lesions were most extensive and severe 3 or 7 days after the administration of NEM. Histological examination of colon on the 3rd day after NEM treatment demonstrated mucosal erosion, oedema and extensive infiltration of neutrophils. The mucosal lesions extended into the submucosa and muscle on the 7th day after NEM treatment. Immunohistochemical studies showed that T cells and macrophages were markedly increased in the lamina propria of colonic mucosa. After 3 weeks, the infiltration of chronic inflammatory cells was observed and regeneration of the mucosa was noticed. The thymus gland was significantly decreased in weight and size on the 3rd day after NEM treatment, but the weight loss of thymus gland was regained in 3 weeks. Transient atrophy of thymus gland was noticed in this colitis model. The phenotypes of thymocytes were not influenced by NEM treatment. It is concluded that the thymus abnormalities in human ulcerative colitis are not induced in this animal model and that other chronic models are necessary for the elucidation of the immunological abnormalities, including thymus abnormalities.