Prevention of Helicobacter pylori infection by lactobacilli in a gnotobiotic murine model

BACKGROUND

Helicobacter pylori is a bacterium which causes gastric inflammatory diseases. Oral inoculation of H pylori usually results in only a temporary colonisation without a successful infection in the stomach of conventional mice in which lactobacilli are the predominant indigenous bacteria.

AIM

To determine whether lactobacilli exert an inhibitory effect on colonisation by H pylori in the stomach.

METHODS

The effects of H pylori on attachment to murine and human gastric epithelial cells and the H pylori mediated release of interleukin-8 (IL-8) by these cells were examined in vitro. Lactobacillus salivarius infected gnotobiotic BALB/c mice and control germ free mice were inoculated orally with H pylori to examine whether L salivarius can inhibit colonisation by H pylori.

RESULTS

L salivarius inhibited both the attachment and IL-8 release in vitro. H pylori could not colonise the stomach of L salivarius infected gnotobiotic BALB/c mice, but colonised in large numbers and subsequently caused active gastritis in germ free mice. In addition, L salivarius given after H pylori implantation could eliminate colonisation by H pylori.

CONCLUSION

These findings suggest the possibility of lactobacilli being used as probiotic agents against H pylori.

Activity of H(+)-ATPase in ruminal bacteria with special reference to acid tolerance

Batch culture experiments showed that permeabilized cells and membranes of Ruminococcus albus and Fibrobacter succinogenes, acid-intolerant celluloytic bacteria, have only one-fourth to one-fifth as much H(+)-ATPase as Megasphaera elsdenii and Streptococcus bovis, which are relatively acid tolerant. Even in the cells grown in continuous culture at pH 7.0, the acid-intolerant bacteria contained less than half as much H(+)-ATPase as the acid-tolerant bacteria. The amounts of H(+)-ATPase in the acid-tolerant bacteria were increased by more than twofold when the cells were grown at the lowest pH permitting growth, whereas little increase was observed in the case of the acid-intolerant bacteria. These results indicate that the acid-intolerant bacteria not only contain smaller amounts of H(+)-ATPase at neutral pH but also have a lower capacity to enhance the level of H(+)-ATPase in response to low pH than the acid-tolerant bacteria. In addition, the H(+)-ATPases of the acid-intolerant bacteria were more sensitive to low pH than those of the acid-tolerant bacteria, although the optimal pHs were similar.

Analysis of interleukin-8 secretion induced by Helicobacter pylori from the gastric epithelial cell line MKN45: a mechanism independent of the intensity of cytotoxicity

Interleukin (IL)-8, a potent chemoattractant and activator of neutrophils, has been implicated to have a major role in the pathogenesis of gastric mucosal injury by Helicobacter pylori infection. We examined the relationship between cytotoxicity and IL-8 secretion induced by H. pylori. Furthermore, whether the vacuolating cytotoxin of H. pylori mediates IL-8 secretion from gastric epithelial cell lines was examined. Among the inflammatory cytokines, messages for IL-6, IL-8 and transforming growth factor-beta 1 were produced by gastric cancer (MKN45) cells in response to exposure to the cytotoxic strain of H. pylori. MKN45 incubated with the viable cytotoxic strain of H. pylori secreted IL-8. In contrast, the supernatant of neither the cytotoxic nor the non-cytotoxic strain induced IL-8 secretion. There was no correlation between IL-8 secretion and the intensity of cytotoxicity. In conclusion, these findings suggest that IL-8 secretion from MKN45 induced by H. pylori is mediated by factors other than cytotoxicity.

The role of histamine in ethanol-induced gastric mucosal injury in the rat

It has been suggested that changes in the micro circulatory system are related to the early production of acute gastric mucosal injury and inflammatory factors such as prostaglandins, histamine, etc., have been considered as contributing to the development of the injury. We assessed the permeability of the gastric mucosa in rats with ethanol-induced acute mucosal injury by measuring the leakage rate of 51chronium-ethylene-diamine-tetraacetic acid (51Cr-EDTA) into the gastric juice. Histamine concentrations in the gastric mucosa was measured by high performance liquid chromatography. The enterochromaffin-like (ECL) cell counts in the gastric mucosa was performed following histamine staining with an enzyme-labeled antibody, and the histamine released due to degranulation was observed. We also investigated the kinetics of endogenous histamine in the gastric mucosa. Five minutes after the administration of ethanol, an increase in permeability, an increase in histamine concentration, and a decrease in ECL cell count were found in the gastric mucosa. These results suggest that endogenous histamine in the gastric mucosa is closely related to the early development of acute gastric mucosal injury.

Characterization of 30-kDa fragments derived from beta-conglycinin degradation process during germination and seedling growth of soybean

The degradation process of beta-conglycinin, a vicilin-type glycosylated storage protein of soybean seeds, during germination and seedling growth was examined by concanavalin A blotting combined with polyacrylamide gel electrophoresis. We detected and analyzed the structures of key intermediary fragments of 30 kDa derived from beta-conglycinin degradation, they were proved to be single-domain type subunits of beta-conglycinin. We show here a degradation process of beta-conglycinin: beta-conglycinin is subjected to limited proteolysis at exposed regions on the molecular surface, like domain junctions, generating 30-kDa single-domain fragments before non-specific proteolysis.

Flagellin gene diversity among Helicobacter pylori strains and IL-8 secretion from gastric epithelial cells

BACKGROUND

To clarify the pathological functions of the virulence factors of Helicobacter pylori, a comparative analysis was carried out on the relationship between motility, flagellar gene polymorphism, vacuolating cytotoxin (VT) production and interleukin-8 (IL-8) induction.

METHODS

Twenty-five strains were examined for restriction fragment length polymorphism (RFLP) of the flagellin gene. Motility was measured using semisolid agar plates. Cytotoxicity was assayed using RK-13 cells. IL-8 secretion was assessed by the enzyme-linked immunosorbent assay (ELISA) methods.

RESULTS

H. pylori was classified into four groups according to their flagellar RFLP. No differences were noted in motility or VT production among the four groups, but a significant difference was noted in IL-8 induction. In addition, highly motile strains produced more IL-8.

CONCLUSION

This flagellar genetic polymorphism may be associated with IL-8 induction.

Prostaglandin E1 potentiation of the spontaneous phasic contraction of rat isolated portal vein by a cyclopiazonic acid-sensitive mechanism

1. The effect of prostaglandin E1 (PGE1) on the spontaneous phasic contraction of the rat isolated portal vein was studied. 2. The isolated portal vein exhibited spontaneous phasic contractions. Removal of Ca2+ from Krebs-Ringer solution or application of nifedipine abolished the spontaneous contraction, indicating that the contraction depends exclusively on Ca2+ influx through L-type Ca2+ channels. On the other hand, cyclopiazonic acid (CPA), a specific inhibitor of Ca(2+)-ATPase of sarcoplasmic reticulum (SR) increased the amplitude of the contractions, suggesting that the SR regulates the spontaneous contractions negatively by sequestration of Ca2+ entering through L-type Ca2+ channels and buffering the rise in cytosolic Ca2+. 3. PGE1 increased the amplitude of the spontaneous contraction in a concentration-dependent manner without affecting the resting tension. The effect was completely abolished by nifedipine. Bay K 8644 and phenylephrine (PE) also increased the amplitude of the contraction in a concentration-dependent manner. PGE1 at a concentration of 1 microM. Bay K 8644 at 100 nM and PE at 30 nM doubled the amplitude, respectively. 4. Pretreatment with 1 microM CPA abolished the effect of PGE1, but the effects of Bay K 8644 and PE were not inhibited by pretreatment with CPA. In contrast, 10 microM ryanodine attenuated the effect of PE without affecting the contractile effect of PGE1. 5. When the SR was depleted of Ca2+ by repeated applications of caffeine in a nominally Ca(2+)-free Krebs-Ringer solution, it took about 120 s to restore the spontaneous contraction after addition of Ca2+ into the solution. In CPA-treated veins, the time taken to restore the contraction was shortened significantly. Pretreatment with 1 microM PGE1 shortened the time to the same extent as pretreatment with CPA did. 6. These results suggest that PGE1 increases the amplitude of the spontaneous phasic contraction by a different mechanism from those by which PE and Bay K 8644 increase it. Inhibition of Ca(2+)-ATPase of the SR might be involved in the vasoactive effect of PGE1.

Olfactory evoked potential produced by electrical stimulation of the human olfactory mucosa

Most physiological studies of the human olfactory system have concentrated on the cortical level; the olfactory bulbar level has been studied rarely. We attempted to stimulate the human olfactory mucosa by electrical pulse to detect the bulbar potentials. Electrical stimulation (2 mA, 0.5 ms) of the human olfactory mucosa evoked a change in potential recorded from the frontal sector of the head. A negative peak of the evoked potential that occurred at 19.4 ms (grand means, n = 5) after stimulation was the clearest. The highest amplitude of the potential was recorded from the frontal sector of the head on the stimulated side. Our findings were similar to the experimental results obtained from the olfactory bulbs of animals. This evoked potential was considered to be the human olfactory bulbar potential. When the subjects were stimulated by applying electricity to the olfactory mucosa, no sensation of smell occurred even though evoked potentials were recorded. Evoked potentials were recorded only when the stimulating electrode was located in the olfactory cleft. When the stimulating electrode was outside the olfactory cleft, the stimulation caused pain. The trigeminal nerve seemed to be stimulated by electricity. Olfactory evoked potentials produced by the electrical stimulation of the human olfactory mucosa should aid the research on human olfactory physiology, and may be applicable to clinical tests of olfactory dysfunction.

cDNA cloning and characterization of rat C5a anaphylatoxin receptor

Activation of the complement cascade plays an essential role in the early stages of inflammation. C5a and its receptor are particularly active in anaphylaxis. To determine the pathological roles played by C5a and C5a receptor (C5aR) in rats, we cloned C5aR cDNA and analyzed distribution of its mRNA in various organs including lung from an LPS-stimulated rat. Furthermore, we generated a polyclonal antiserum which specifically recognizes rat C5aR, as confirmed by its specific interaction with cells transfected with rat C5aR cDNA.

Indirect photometric detection of inorganic anions in microcolumn ion chromatography using octadecylsilica immobilized with bovine serum albumin as stationary phase

Octadecylsilica immobilized with bovine serum albumin was capable of separating inorganic anions. The stationary phase retained anions under acidic conditions, and the use of aqueous solution containing sodium iodide and tartaric acid as the eluent allowed the indirect photometric determination of chloride and nitrate in water and serum samples. The mobile phase conditions were optimized.

Binding specificity of Lactobacillus to glycolipids

Lactobacillus, a representative useful bacterium, in the intestinal tract was found to bind to some specific glycosphingolipids, like the pathogenic intestinal bacteria. Thin layer chromatography overlay assays using rabbit antiserum against Lactobacillus casei revealed that the bacteria bound to GA1 and trihexosylceramide strongly, but not to any gangliosides. The bacteria generally bound to glycosphingolipids having short sugar chains and galactosyl moiety in the non-reducing terminal. L.casei did not bind to GM1, but bound to the product after sialidase treatment, GA1. This indicated that sialic acid inhibited the adhesion of L.casei to tissues. L.casei actually bound nonacid glycosphingolipids but not acid glycosphingolipids extracted from the small intestinal mucosa of rats.

[Involvement of endogenous nitric oxide in the regulation of distal colonic motility in anaesthetized rat]

The contribution of the endogenous nitric oxide (NO) to the distal colonic motility was investigated by inhibiting NO production using NO synthase inhibitor, NG-monomethyl-L-arginine (L-NMMA). The experiment was carried out in the anaesthetized rat, which was vagotomized and pretreated with guanethidine, phentolamine and propranolol. The colonic motility was evaluated by changes in the increase in intraluminal pressure of the distal colon. L-NMMA infusion (100mg/kg iv) in the presence of atropine (1 mg/kg iv) resulted in a significant increase in arterial blood pressure and intraluminal pressure. The following L-arginine infusion (100mg/kg iv) restored blood pressure and intraluminal pressure to the control level. In contrast, L-NMMA infusion in the absence of atropine resulted in no change in intraluminal pressure with a significant increase in arterial blood pressure. These results indicate that there are NO-dependent and nondependent mechanisms to regulate the distal colonic motility.

Clinicopathologic evaluation of immunohistochemical E-cadherin expression in human gastric carcinomas

BACKGROUND

E-cadherin plays a crucial role in cell-cell adhesion in epithelial tissues. Recent studies have shown a correlation between decreased E-cadherin expression and cancer cell detachment.

METHODS

The expression of E-cadherin was immunohistochemically analyzed using antihuman E-cadherin antibody in 121 cases of human gastric carcinoma.

RESULTS

In noncancerous areas, the epithelial cells, including those with intestinal metaplasia, were stained positively in the plasma membrane. In contrast, E-cadherin expression of the cancer cells varied from case to case in primary and secondary sites. Tumors with a decrease in E-cadherin occurred significantly more frequently in undifferentiated adenocarcinoma (P < 0.05) and scirrhous type (P < 0.01). The rate of E-cadherin-negative tumors was higher in patients with peritoneal metastasis (P < 0.01) or in those with distant lymph node metastasis (P < 0.01), though the tumors with liver metastasis had relatively positive E-cadherin expression. Patterns of initial recurrence had similar results. Reduction or loss of E-cadherin expression correlated with shorter survival in patients after curative operation regardless of stage of disease.

CONCLUSIONS

The decreased E-cadherin expression correlates with dedifferentiation, infiltrative tumor growth, distant metastasis, and poor survival for patients with gastric carcinoma. Thus, immunohistochemical study of E-cadherin may have clinicopathologic value for patients with gastric carcinoma.

Prognostic value of EGFR and TGF-alpha in early laryngeal cancer treated with radiotherapy

The purpose of this study was to determine the overexpression of both epidermal growth factor receptor (EGFR) and transforming growth factor-alpha (TGF-alpha) (a ligand of EGFR) in early laryngeal squamous cell carcinoma. In addition, we attempted to evaluate the prognostic values of our findings. Expression of EGFR and TGF-alpha in tumor tissue was examined immunohistochemically in 68 patients who had been treated with radiotherapy for early laryngeal cancer. Overexpression of the two factors was noted in 42.6% and 55.9%, respectively. No significant differences due to age, tumor size, and location or grade of cancer tissues were seen. Higher survival rates, found in patients with EGFR (-) and TGF-alpha (-) tumors as compared with those with EGFR (+) and TGF-alpha (+) (97.4%, 100% and 86.2%, 86.8%, respectively), were not statistically significant. The recurrence rates were similar between EGFR (+) and EGFR (-) (37.9% and 35.9%, respectively). However, the recurrence rate in patients with TGF-alpha (+) was significantly higher (57.9%) than in those with TGF-alpha (-) (10%; P<.01). Therefore overexpression of TGF-alpha may be an important indicator for recurrence in patients with early laryngeal squamous cell carcinoma treated by irradiation.

Progression in gastric carcinoma relative to the ratio of CD44 epithelial variant transcript to CD44 hematopoietic variant transcript

BACKGROUND

It has been suggested that CD44 splice variants play a role in the progression of certain epithelial cancers and non-Hodgkin's lymphoma. In this study, we investigated the epithelial variant/hematopoietic variant (E/H) ratio (the amount of the CD44 epithelial variant transcript relative to the CD44 hematopoietic variant transcript) in human gastric carcinoma compared with normal gastric mucosa.

METHODS

The ratio was determined for tumors and adjacent noncancerous mucosa from 30 gastric carcinoma patients using reverse transcription-polymerase chain reaction and Southern blotting. We also determined the tumor (T)E/H--noncancerous mucosa (N)E/H (the difference between E/H ratios of tumor tissue and adjacent noncancerous mucosa) and examined these measurements for correlations with the pathologic features of gastric carcinoma, as well as for their usefulness as an indicator of tumor progression.

RESULTS

The E/H ratio in tumor tissue was significantly higher than in adjacent noncancerous mucosa (P < 0.01). The TE/H--NE/H in patients with lymph node metastases was 0.16 +/- 0.11, compared with 0.07 +/- 0.08 in cases without lymph node metastases (P < 0.05). Significant correlations also were observed between the TE/H--NE/H and the depth of invasion, blood vessel invasion, and lymphatic vessel invasion (P < 0.03, P < 0.03, and P < 0.01, respectively).

CONCLUSIONS

Our results suggest that increases in the E/H ratio may be a useful indicator of progression in gastric carcinoma.

Overloading a muscle does not alter the rate of motoneuronal loss in aged rats

Effects of increased activity on neuronal cell death was investigated in the motor nuclei innervating normal and overloaded medial gastrocnemius (MG) muscles of Fischer 344 rats. The MG muscle was overloaded by the unilateral surgical ablation of synergists at the age of 17 months (group A) or 24 months (group B). When the rats reached the age of 24 and 28 months (group A) or 30 months (group B), motoneurons innervating the MG muscle were labeled bilaterally with horseradish peroxidase injected into the MG nerve. The wet weight of the muscle on the operated side was consistently heavier than that of the contralateral, intact side. The number of labeled neurons decreased with advancing age, and there was no difference in the magnitude of decline found between motor nuclei innervating intact and hypertrophied muscles. Thus, overloading the MG muscle did not retard or accelerate the age-related loss of motoneurons innervating this muscle. These findings indicate that the causal relationship between motoneuronal activity and death with advancing age needs to be studied further.

Progression in gastric carcinoma relative to the ratio of CD44 epithelial variant transcript to CD44 hematopoietic variant transcript

BACKGROUND

It has been suggested that CD44 splice variants play a role in the progression of certain epithelial cancers and non-Hodgkin's lymphoma. In this study, we investigated the epithelial variant/hematopoietic variant (E/H) ratio (the amount of the CD44 epithelial variant transcript relative to the CD44 hematopoietic variant transcript) in human gastric carcinoma compared with normal gastric mucosa.

METHODS

The ratio was determined for tumors and adjacent noncancerous mucosa from 30 gastric carcinoma patients using reverse transcription-polymerase chain reaction and Southern blotting. We also determined the tumor (T)E/H--noncancerous mucosa (N)E/H (the difference between E/H ratios of tumor tissue and adjacent noncancerous mucosa) and examined these measurements for correlations with the pathologic features of gastric carcinoma, as well as for their usefulness as an indicator of tumor progression.

RESULTS

The E/H ratio in tumor tissue was significantly higher than in adjacent noncancerous mucosa (P < 0.01). The TE/H--NE/H in patients with lymph node metastases was 0.16 +/- 0.11, compared with 0.07 +/- 0.08 in cases without lymph node metastases (P < 0.05). Significant correlations also were observed between the TE/H--NE/H and the depth of invasion, blood vessel invasion, and lymphatic vessel invasion (P < 0.03, P < 0.03, and P < 0.01, respectively).

CONCLUSIONS

Our results suggest that increases in the E/H ratio may be a useful indicator of progression in gastric carcinoma.

The 5'-flanking region of the human smooth muscle cell calponin gene contains a cis-acting domain for interaction with a methylated DNA-binding transcription repressor

The human smooth muscle cell (SMC) calponin gene, which is composed of seven exons and six introns, spanning an approximately 11.2 kilobase (kb) genomic DNA, has been isolated and characterized by sequence analysis. As determined by primer extension mapping and rapid amplification of mRNA transcripts, a major transcription start site of the calponin gene is located at 101 base-pairs (bp) upstream of the ATG start codon. A striking feature of the 5'-flanking, 5'-untranslated, and amino-terminal protein coding regions is the presence of an Alu repetitive sequence and a stretch of DNA sequence identified using a methyl CpG-binding protein affinity column [Cross, S.H., Charlton, J.A., Nan, X., and Bird, A.P. (1994) Nature Genet, 6,236-244]. The results of this study provide a new insight into the molecular mechanism underlying regulation of SMC-lineage specific gene expression.

[Diagnosis of pulmonary aspergillosis in cases with cavity as sequela of tuberculosis]

Non-invasive pulmonary aspergillosis is frequently seen in cases with cavity as sequela of tuberculosis. Diagnosis of non-invasive pulmonary aspergillosis is not easy except for cases whose chest X-ray findings show a typical fungus ball. How to diagnose pulmonary aspergillosis was studied in 21 patients who showed changes in the radiological findings of cavity as sequela of tuberculosis. We made sputum culture of Aspergillus, measurement of precipitin antibody titer to Aspergillus fumigatus and measurement of PASTOREX ASPERGILLUS in serum and sputum on the 21 patients (group A). PASTOREX ASPERGILLUS in sputum was evaluated in three grades: 1+ approximately 3+. We diagnosed 14 patients as pulmonary aspergillosis (PA group) among the 21 patients taking into account the chest X-ray findings and the results of the above-stated investigations. The types of chest X-ray findings of these 14 patients were fungus ball type (FB) in 2 patients, productive aspergilloma on the inner wall of a cavity (PAIC) in 8, mixed type with FB and PAIC in 2 and non-specific change in 2. However, there were 3 patients with the chest X-ray findings suggestive of PAIC in 7 patients (non-PA group) who were not diagnosed as pulmonary aspergillosis. Sputum culture were positive in 11 patients of PA group (79%) and negative in all patients of non-PA group. Precipitin antibody were positive in 8 patients of PA group (67%) and negative in all patients of non-PA group. PASTOREX ASPERGILLUS in serum were negative in all 21 patients. PASTOREX ASPERGILLUS in sputum were 3+ (+3) in all 14 patients of PA group and in 2 patients of non-PA group and 2+ (+2) in 2 patients of non-PA group. 12 patients of PA group were treated by antifungal agents and 11 patients responded well to the treatment. We also made sputum culture of Aspergillus and measurement of PASTOREX ASPERGILLUS in sputum on 14 patients (group B) who had respiratory diseases with stable cavities and 17 patients (group C) who had respiratory diseases without a cavity. In group B, sputum culture were positive in 1 patient and PASTOREX ASPERGILLUS in sputum were 3+ (+3) in 2 patients, 2+ (+2) in 1 and 1+ (+) in 2. In group C, sputum culture were negative in all patients and PASTOREX ASPERGILLUS in sputum were 3+ (+3) in 1 patient, 2+ (+2) in 3 and 1+ (+) in 2. Measurement of PASTOREX in sputum was a useful tool to diagnose non-invasive aspergillosis in addition to sputum culture and measurement of precipitin antibody titer. The sensitivity of PASTOREX in sputum was high but its specificity was low, however, its specificity could be raised by applying semi-quantitative analysis of PASTOREX in sputum.

The effect of Helicobacter pylori on gastric acid secretion by isolated parietal cells from a guinea pig. Association with production of vacuolating toxin by H. pylori

BACKGROUND

One of the features of Helicobacter pylori infection in the human stomach seems to be disordered gastric acid secretion. The effect of vacuolating toxin (VT) produced by H. pylori on gastric acid secretion was examined.

METHODS

VT(+)(toxigenic) and VT(-)(nontoxigenic) strains of H. pylori were cultured in brucella broth. The culture supernatant was added to isolated parietal cells, and acid secretion and intracellular adenosine 3'5'-cyclic phosphate (cAMP) and Ca2+ levels were measured with the 14C-aminopyrine (14C-AP) method, with 125I radioimmunoassay (RIA), and with the fura-2 fluorescence method, respectively.

RESULTS

In the VT(+) strain a considerable inhibitory effect on 14C-AP accumulation was observed. However, the VT(-) strain had no significant effect on intracellular c-AMP and Ca2+.

CONCLUSIONS

The VT(+) strain of H. pylori has an inhibitory effect on gastric acid secretion, whereas the VT(-) strain does not. This inhibitory effect was not associated with the response of second messengers. It is speculated that VT produced by H. pylori has a direct action on H(+)-K+ adenosine triphosphatase in parietal cells.

FISH localization of human cytoplasmic actin genes ACTB to 7p22 and ACTG1 to 17q25 and characterization of related pseudogenes

Human beta- and gamma-cytoplasmic actin genes (ACTB and ACTG1) were mapped to chromosomes 7p22 and 17q25, respectively, by fluorescence in situ hybridization (FISH). Four processed pseudogenes, beta-actin-related ACTBP9 and gamma-actin-related ACTGP1, ACTGP3, and ACTGP9, were isolated from human libraries. By PCR of somatic cell hybrid DNAs, ACTBP9 and two beta-actin-related pseudogenes (ACTBP7 and ACTBP8) were mapped to human chromosomes 18, 15, and 6, respectively. The gamma-actin-related pseudogenes were mapped by FISH to chromosomes 3q23 (ACTGP1), 20p13 (ACTGP3), and 6p21.1 (ACTGP9).

Progression in gastric carcinoma relative to the ratio of CD44 epithelial variant transcript to CD44 hematopoietic variant transcript

BACKGROUND

It has been suggested that CD44 splice variants play a role in the progression of certain epithelial cancers and non-Hodgkin's lymphoma. In this study, we investigated the epithelial variant/hematopoietic variant (E/H) ratio (the amount of the CD44 epithelial variant transcript relative to the CD44 hematopoietic variant transcript) in human gastric carcinoma compared with normal gastric mucosa.

METHODS

The ratio was determined for tumors and adjacent noncancerous mucosa from 30 gastric carcinoma patients using reverse transcription-polymerase chain reaction and Southern blotting. We also determined the tumor (T)E/H--noncancerous mucosa (N)E/H (the difference between E/H ratios of tumor tissue and adjacent noncancerous mucosa) and examined these measurements for correlations with the pathologic features of gastric carcinoma, as well as for their usefulness as an indicator of tumor progression.

RESULTS

The E/H ratio in tumor tissue was significantly higher than in adjacent noncancerous mucosa (P < 0.01). The TE/H--NE/H in patients with lymph node metastases was 0.16 +/- 0.11, compared with 0.07 +/- 0.08 in cases without lymph node metastases (P < 0.05). Significant correlations also were observed between the TE/H--NE/H and the depth of invasion, blood vessel invasion, and lymphatic vessel invasion (P < 0.03, P < 0.03, and P < 0.01, respectively).

CONCLUSIONS

Our results suggest that increases in the E/H ratio may be a useful indicator of progression in gastric carcinoma.

Dynamic and static sensitivities of muscle spindle primary endings in aged rats to ramp stretch

Responses of the presumed primary sensory endings of de-efferented muscle spindles to a ramp stretch were investigated in the medial gastrocnemius muscle of male Fischer 344 rats of two age groups (i.e. 10-14 and 28-30 months) anesthetized with urethane and chloralose. The static sensitivity was similar for both middle-aged and aged rats, although the discharge frequency was lower for aged rats when compared at the same muscle length. The value of the dynamic index was significantly lower in aged rats than in middle-aged rats, suggesting a decrease in the dynamic sensitivity of muscle spindle primary endings in aged rats.

Clinicopathologic evaluation of immunohistochemical E-cadherin expression in human gastric carcinomas

BACKGROUND

E-cadherin plays a crucial role in cell-cell adhesion in epithelial tissues. Recent studies have shown a correlation between decreased E-cadherin expression and cancer cell detachment.

METHODS

The expression of E-cadherin was immunohistochemically analyzed using antihuman E-cadherin antibody in 121 cases of human gastric carcinoma.

RESULTS

In noncancerous areas, the epithelial cells, including those with intestinal metaplasia, were stained positively in the plasma membrane. In contrast, E-cadherin expression of the cancer cells varied from case to case in primary and secondary sites. Tumors with a decrease in E-cadherin occurred significantly more frequently in undifferentiated adenocarcinoma (P < 0.05) and scirrhous type (P < 0.01). The rate of E-cadherin-negative tumors was higher in patients with peritoneal metastasis (P < 0.01) or in those with distant lymph node metastasis (P < 0.01), though the tumors with liver metastasis had relatively positive E-cadherin expression. Patterns of initial recurrence had similar results. Reduction or loss of E-cadherin expression correlated with shorter survival in patients after curative operation regardless of stage of disease.

CONCLUSIONS

The decreased E-cadherin expression correlates with dedifferentiation, infiltrative tumor growth, distant metastasis, and poor survival for patients with gastric carcinoma. Thus, immunohistochemical study of E-cadherin may have clinicopathologic value for patients with gastric carcinoma.

[Histogenesis of central neurocytoma: an immunohistochemical and electronmicroscopic study of four cases]

Four intraventricular central neurocytomas were studied histopathologically and intriguing findings were obtained with regard to the histogenesis of this tumor. The cases included 3 males and 1 female aged 17-25. The tumors had developed in the regions from the lateral to the third ventricles and were surgically removed in all the cases. A honeycomb appearance was recognized on H&E staining, and the calcification and latticed vascular findings closely mimicked the appearance of oligodendroglioma. A characteristic wide eosinophilic fibrous stroma was observed frequently. Immunohistochemically, all four cases were NSE-positive and strongly synaptophysin-positive, and by electronmicroscopy, neurosecretory granules and microtubules were observed in all cases and typical synapse structures in 2 cases. GFAP immunoreactivity and glial differentiation, including ependymal cells were exhibited electronmicroscopically, such as glial fibrils, basal bodies, centrioles and 9 + 1 patterned cilia-like structures in 2 cases. These findings suggest that central neurocytoma is an embryonal tumor in the wide sense, originating from the germinal matrix cell of the lateral ventricles and possessing multipotency, with potent differentiation from mature neurons.

Roles of sigma receptors in isolated guinea pig parietal cells

Sigma receptor involvement in the oxyntic mechanism of gastric parietal cells was investigated using isolated guinea pig parietal cells. Using the 14C-aminopyrine accumulation method, di(orthotolyl)guanidine (DTG), a sigma receptor agonist, demonstrated peak stimulation of acid production at a concentration of 5 x 10(-5) M. The DTG-induced stimulatory effect on 14C-aminopyrine accumulation in preparations enriched in parietal cells was inhibited by haloperidol, a DTG inhibitor, and omeprazole, a proton pump inhibitor, in a concentration-dependent manner. Assessment of the interaction between DTG and agonists for histamine, gastrin, and muscarine receptors demonstrated a potentiating interaction effect on acid production only when parietal cells were exposed to both DTG and histamine. A receptor-binding assay using 3H-DTG revealed two sigma receptor subtypes, sigma 1 and sigma 2, on the crude membranes of parietal cells. There was a direct relationship between DTG dose and intracellular Ca2+ concentration, but there was no change in intracellular cyclic adenosine 5'-monophosphate (cAMP) concentration when parietal cells were exposed to DTG. These results demonstrate that sigma receptors exist on guinea pig gastric parietal cells and suggest that they play a role in acid production via an increase in intracellular Ca2+ concentration.

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

BACKGROUND

Several studies have revealed a correlation between sialosyl Tn antigen (STN) and certain clinicopathologic features of various cancers, and that STN is an independent prognostic factor. However, the clinical significance of the expression of STN in gastric cancer has not been reported. Thus, the purpose of this study was to evaluate immunohistochemically the clinical significance of expression of STN in gastric cancer.

METHODS

The expression of STN in surgically resected specimens of human gastric cancer was evaluated immunohistochemically using a monoclonal antibody (TKH-2), in 60 patients whose serum STN levels were measured and in 54 patients with advanced cancer who had been followed for more than 5 years after gastrectomy. The correlations between the level of STN expression and clinicopathologic factors were analyzed. The staining intensity was graded as follows: (-), less than 5% of the cancer cells expressed STN; (+), 5-50%; (++), more than 50%.

RESULTS

Sialosyl TN antigen staining was detected mainly on the cell membrane, in the cytoplasm, and in the luminal contents, and 57.2% of the 60 specimens expressed STN, whereas the corresponding value for positive serum levels was 15%. A higher percentage of advanced tumors expressed STN than did the early cases, but the difference was not statistically significant. All cases with strong staining, the (++) cases, were advanced cases either with lymph node metastases or with cancer invading in or beyond the muscle layer proper. The expression of STN appeared to be related to the clinical stage, the extent of cancer invasion, and the presence of lymph node metastases. Sialosyl TN antigen was detected in the serum in less than 6% of the patients whose tumors were (-) or (+) for STN expression, and in 86.7% of the patients whose tumors expressed high levels of STN (++). The estimated 5-year survival in advanced cases (Stage III) was significantly better in those with negative STN expression than in those with positive STN expression (P < 0.01).

CONCLUSIONS

These results suggest that STN may be a useful marker associated with the prognosis of patients with advanced gastric cancer.

Multiple isoforms of guinea pig decay-accelerating factor (DAF) generated by alternative splicing

Human decay-accelerating factor (DAF, CD55), which is one of the regulators of complement activation (RCA), prevents complement activation on homologous cell membranes, resulting in a functional discrimination between self cells and invading microorganisms. DAF is a glycosylphosphatidylinositol (GPI)-anchored glycoprotein and has been identified at the molecular level only in primates. We have isolated guinea pig DAF cDNA clones from a spleen library and identified six different classes. All encode the same four short consensus repeat domains with 58% amino acid sequence identity to human DAF, but show variability in the C-terminal region. Alternative splicing of two optional exons generates transmembrane, GPI-anchored, and secreted forms of guinea pig DAF, and differential usage of splice sites in the single exon composed of internally quintuplicated sequences generates variable Ser/Thr-rich regions. Multiple isoforms were expressed ubiquitously in all tissues and cells tested. Similar variability in the Ser/Thr-rich region has been reported in human membrane cofactor protein (MCP), another membrane inhibitor of the RCA family. There seems to be a common ancestral sequence in DAF and MCP consisting of a Ser/Thr-rich region, but obviously multiplication occurred independently, indicating the importance of variability of the Ser/Thr-rich region for the effective regulation of complement activation.

Multiple isoforms of guinea pig decay-accelerating factor (DAF) generated by alternative splicing

Human decay-accelerating factor (DAF, CD55), which is one of the regulators of complement activation (RCA), prevents complement activation on homologous cell membranes, resulting in a functional discrimination between self cells and invading microorganisms. DAF is a glycosylphosphatidylinositol (GPI)-anchored glycoprotein and has been identified at the molecular level only in primates. We have isolated guinea pig DAF cDNA clones from a spleen library and identified six different classes. All encode the same four short consensus repeat domains with 58% amino acid sequence identity to human DAF, but show variability in the C-terminal region. Alternative splicing of two optional exons generates transmembrane, GPI-anchored, and secreted forms of guinea pig DAF, and differential usage of splice sites in the single exon composed of internally quintuplicated sequences generates variable Ser/Thr-rich regions. Multiple isoforms were expressed ubiquitously in all tissues and cells tested. Similar variability in the Ser/Thr-rich region has been reported in human membrane cofactor protein (MCP), another membrane inhibitor of the RCA family. There seems to be a common ancestral sequence in DAF and MCP consisting of a Ser/Thr-rich region, but obviously multiplication occurred independently, indicating the importance of variability of the Ser/Thr-rich region for the effective regulation of complement activation.

Construction and characterization of adenoviral vector expressing biologically active brain-derived neurotrophic factor

To deliver brain-derived neurotrophic factor (BDNF) to the central nervous system, we sought to attain adenovirus-mediated transfer and expression of the gene in both in vitro and in vivo experiments. For this purpose, we constructed AxCA-BDNF, a recombinant adenoviral vector containing the BDNF cDNA expression cassette. Reverse transcription polymerase chain reaction analyses of the infected HeLa cells and the transduced mouse brain revealed successful expression of the BDNF gene both in vitro and in vivo. The results of a survival assay of chick dorsal root ganglion cells showed that the produced BDNF was biologically active. We consider, therefore, this newly constructed recombinant adenovirus to be a useful tool to deliver BDNF to degenerating neurons and to be applicable to gene therapy of neurodegenerative diseases and nerve trauma.

Changes in gastric acid secretion and fasting gastrin levels during healing of duodenal ulcers

Changes in gastric acid secretion and fasting gastrin levels (FGL) during the healing of duodenal ulcers were investigated. Duodenal ulcers were classified into three stages, with regard to healing, active, healing, and healed (scar). As controls, 49 individuals without gastro-duodenal lesions were used. We found that gastric acid secretion was highest during the active stage, thereafter decreasing during the healing and healed stages. Gastric acid secretion was lowest in the normal subjects, and significant differences were found between the 3 stages of the duodenal ulcers. FGL was also highest in the active stage, thereafter decreasing during the healing and healed stages. In the follow-up of 10 doudenal ulcer patients, gastric acid secretion and FGL were higher in the active than in the healed stage. It was concluded that gastric acid secretion and FGL change during the healing of duodenal ulcers. The increase of gastric acid secretion and FGL seen in the active stage appears to be implicated in the pathogenesis of the duodenal ulcer.

Transcriptional repression of smooth-muscle alpha-actin gene associated with human papillomavirus type 16 E7 expression

To explore the role of the E7 viral oncogene from human papillomavirus type 16 (HPV 16) in the regulation of cytoskeletal organization, we investigated alterations in particular cytoskeletal components in rat embryonal fibroblasts and three transformants of rat embryonal fibroblast cells produced by transfections with HPV16 E7 alone (TF1), HPV16 E7 plus adenovirus type 5 E1B (TF3), and HPV16 E7 plus activated Ha-ras (TF4). Marked reductions in smooth-muscle (SM) alpha-actin content and disrupted organization of stress fibers detected by anti-SM alpha-actin antibody were evident in all the transformants. These cytoskeletal manifestations were associated with a significant reduction in the mRNAs in these cells. Transcriptional repression by the E7 gene was observed after transient transfection of a chloramphenicol acetyltransferase reporter gene with SM alpha-actin gene promoter. Nucleotides -123 to -39 of the SM alpha-actin gene promoter were required for the HPV16 E7 transcriptional repression as shown by the chloramphenicol acetyltransferase assay. The downregulation of this actin isoform mediated by the E7 oncoprotein may play an important role in cell transformation by HPV16.

7-(4-[4-(2,3-Dichlorophenyl)-1-piperazinyl]butyloxy)-3,4-dihydro-2(1H)-quinolinone (OPC-14597), a new putative antipsychotic drug with both presynaptic dopamine autoreceptor agonistic activity and postsynaptic D2 receptor antagonistic activity

The effects of 7-(4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy)-3,4-dihydro-2 (1H)- quinolinone (OPC-14597), a derivative of the dopamine (DA) autoreceptor agonist 7-(3-[4-(2,3-dimethylphenyl)piperazinyl]propoxy)-2(1H)-quinolinone (OPC-4392), on DA receptors were biochemically and behaviorally studied and compared with those of OPC-4392. Both OPC-14597 and OPC-4392 inhibited reserpine- and gamma-butyrolactone (GBL)-induced increase in tyrosine hydroxylase activity in the mouse and rat brain. The effects of OPC-14597 were comparable to those of OPC-4392 and were completely antagonized by haloperidol. OPC-14597, unlike apomorphine, did not evoke postsynaptic DA receptor-stimulating behavioral signs such as hyperlocomotion in the reserpinized mice and contralateral rotation in rats with unilateral striatal 6-hydroxydopamine lesions. Both OPC-14597 and OPC-4392 inhibited such apomorphine-induced postsynaptic behavioral changes as stereotypy and hyperlocomotion in mice and rats and rotation in rats with unilateral striatal kainic acid lesions. The anti-apomorphine effects of OPC-14597 were about 30 to 140 times greater than those of OPC-4392 and were observed at doses that inhibit the increases in tyrosine hydroxylase activity. The affinities of OPC-14597 for 3H-spiperone-labeled D2 receptors in the rat frontal cortex, limbic forebrain and striatum were higher than those of OPC-4392. These results suggest that OPC-14597 is a unique antipsychotic drug candidate, being a DA autoreceptor agonist that has a stronger postsynaptic D2 receptor antagonistic activity than that of OPC-4392.

Expression of EGF, EGFR and PCNA in laryngeal lesions

The expression of EGF/EGFR in 47 laryngeal surgical specimens from 44 patients was examined. PCNA analysis as an index of proliferating cells was also performed in 32 cases of laryngeal cancer, six cases of pre-cancerous lesions and nine cases of normal laryngeal mucosa. EGFR failed to show a significant correlation with tumour behaviour, but EGF expression was statistically significantly higher in malignant (SCC) than in non-malignant tissues (pre-cancerous and normal tissues) (p < 0.006), and PCNA also showed a statistically significant difference (p < 0.016) between the two. In malignant tissues when EGF/EGFR in 'double-positive' and 'double-negative' cases was compared, a statistically significant difference in PCNA was found (p < 0.029); but this was not seen in non-malignant tissues. Our results support the hypothesis that an autocrime mechanism exists in laryngeal cancer and in this mechanism EGF may play an important role in tumour progression, especially when EGFR is overexpressed.

[A clinical experience of DNA probe method for identifying Mycobacterium avium and Mycobacterium intracellulare]

In Japan the number of patient infected with M. avium complex (MAC) has been increasing in contrast to a decrease of pulmonary tuberculosis. DNA probe method enabled us be able to differentiate an isolated MAC into M. avium and M. intracellulare. From 1991 to 1992, we performed an investigation to apply this new technique of the DNA probe method on 52 patients of atypical mycobacteriosis diagnosed as infected with MAC by the ordinary method at the Higashi Nagoya National Hospital. The group consisted of 27 males and 25 females. M. avium infection was found in 39 patients (M. avium group) and M. intracellulare in 16 patients (M. intracellulare group). No significant gender difference was found between two groups. The M. avium group showed more complications in contrast to the M. intracellulare group. As complications in the M. avium group, pulmonary aspergillus infection, bacterial pneumonia and bronchiectasis were found in 4, 3 and 2 cases, respectively. The rate of drug resistance to antituberculosis drugs was high in the both groups. Chemotherapy with isoniazid (INH) rifampin (RFP) and streptomycin (SM) in five patients, that with INH, RFP and ethambutol (EB) in three were found to be effective after 4 months treatment. Three patients in M. avium group died of respiratory failure, aspergillus infection and renal failure. In contrast the prognosis of patients in the M. intracellulare group seemed to be better as there was no fatal case. We conclude that DNA probe method is useful to differentiate between M. avium and M. intracellulare, and enable us to select more appropriate selection of the chemotherapy and to assess of the prognosis.

A recurrent case of spontaneous mediastinal emphysema

The first case of spontaneous mediastinal emphysema was reported by Hamman et al. in 1939. It is a rare condition that primarily occurs in young adults. In many instances, spontaneous mediastinal emphysema is caused by yelling, shouting or active exercise, but the cause is often unknown. It is rare for cases of spontaneous mediastinal emphysema to recur. Recently, we experienced a recurrent case of spontaneous mediastinal emphysema in a patient with a duodenal ulcer. Vomiting appeared to be the cause of the recurrence in our patient. Of the 58 patients with spontaneous mediastinal emphysema who have been reported in Japan so far, recurrences were documented only in our patient and two others.