The measurement of gastric emptying in conscious rats by monitoring serial changes in serum acetaminophen level

A method for evaluation of gastric emptying via monitoring serial serum levels of acetaminophen (APAP) as an indicator, without involving animal sacrifice, has been developed in conscious rats. We administered orally suspended test meals of 0.5, 1, 2, or 4 mL/rat each, containing 20 mg APAP. The animals were repeatedly bleed at 15, 30, 45, 60, or 90 min after APAP treatment. Serum APAP level was determined by a high-performance liquid chromatography. As a result, a 2-mL meal was found optimal to attain continuous levels of APAP in serum. The APAP method showed a close correlation (r = 0.77) with the phenol red method, a standard procedure for quantitative detection of gastric emptying entailing rat sacrifice. The blood loss (approximately 2 mL) resulting from the APAP method did not significantly modify the rate of gastric emptying. In addition, data was presented to substantiate the validity of the APAP method in demonstrating enhancement and inhibition of gastric emptying using cisapride and cholecystokinin-octapeptide (CCK), respectively. These results suggest that the APAP method is easy, versatile, and reliable, and requires only a minimal number of animals for the evaluation of sequential changes in gastric emptying.

Protective effect of DM-9384, a novel pyrrolidone derivative, against experimental cerebral anoxia

The protective effects of DM-9384 [N-(2,6-dimethylphenyl)-2-(2-oxo- 1-pyrrolidinyl) acetamide] against cerebral anoxia were investigated using various animal models. Oral administration of DM-9384 resulted in a significant prolongation of survival time in mice and rats subjected to the normobaric hypoxia; its minimal effective doses were 30 and 10 mg/kg, respectively. A significant protection by this drug against hypobaric hypoxia, histotoxic anoxia and cerebral ischemia also occurred in mice at a dose of 100 mg/kg, p.o. Bifemelane (100-300 mg/kg, p.o.) was protective against these models except for hypobaric hypoxia, and the effects of piracetam, aniracetam and pramiracetam (1000 mg/kg, p.o.) were variable depending on the type of anoxia model used. DM-9384 (100 mg/kg and lower) attenuated the hypolocomotion and the disturbance of cerebral energy metabolism such as a decrease in ATP, an increase in lactate and lactate/pyruvate ratio induced by hypoxia in rats. The spontaneous motor activity, uptake and utilization of brain glucose in normal animals, however, were not influenced by this drug. Based on these results, DM-9384 is characterized as a broad spectrum anti-anoxic drug with negligible CNS depression, and the cerebral protective effect of this drug may be, at least in part, attributable to its ability to improve the cerebral energy metabolic disturbance.

Isolation of cis-3-Amino-l-Proline from Cultured Mycelia of Morchella esculenta Fr

cis-3-Amino-l-proline, identified once as a nonprotein amino acid from the fruiting bodies of Morchella esculenta Fr., was isolated also from the growth medium and cultured mycelia of the same fungus.

Enhancing effect of DQ-2511 on gastric emptying of spontaneously hypertensive rats

The present study was designed to clarify the potential of DQ-2511 (3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl]carbamoyl]methyl] amino-N-methylbenzamide: ecabapide) as a gastroprokinetic agent in spontaneously hypertensive rats (SHR). The gastric emptying of SHR was clearly retarded relative to that of weight-matched normotensive Wistar-Kyoto (WKY) rats when evaluated by the acetaminophen (APAP) method with the semi-solid test meal. There was, however, no significant difference between both strains in gastric mucosal blood flow (GMBF) determined by means of a laser doppler flowmetry. A 2-week treatment of SHR with DQ-2511 (1 mg/kg, oral) stimulated gastric emptying without affecting body weight gain or indirect systolic blood pressure (SBP), whereas cisapride (3 and 10 mg/kg, oral) had no effect under the same conditions. The pharmacological characteristics of DQ-2511 as a gastroprokinetic agent are discussed on the basis of these results.

von Recklinghausen's disease associated with somatostatin-rich duodenal carcinoid (somatostatinoma), medullary thyroid carcinoma and diffuse adrenal medullary hyperplasia

This report describes the concomitant occurrence of a somatostatin-rich duodenal carcinoid, a medullary thyroid carcinoma and a diffuse adrenal medullary hyperplasia in a patient with von Recklinghausen's disease. A 50-year-old Japanese man died from lung metastasis of a malignant schwannoma. In addition to extensive viscero-cutaneous neurofibromatosis, two different types of neuroendocrine tumors were found in the duodenum and thyroid gland at autopsy. The duodenal tumor, which was located in the second portion, showed the histologic appearance of a carcinoid tumor with glandular differentiation and psammoma-bodies. Immunohistochemically the tumor cells were intensely positive for somatostatin. The thyroid tumor was composed of nests of tumor cells arranged in an endocrine pattern, and showed immunoreactivity for calcitonin. A review of the literature revealed no previously reported case of concomitant occurrence of duodenal somatostatinoma and medullary thyroid carcinoma in a single patient with von Recklinghausen's disease. Morphometric analysis of adrenal glands disclosed the presence of diffuse medullary hyperplasia. Thus, the present case exhibited a similarity in some respects with multiple endocrine neoplasia (MEN) syndrome, Type IIa or IIb.

Partial purification and properties of gamma-glutamyltranspeptidase from mycelia of Morchella esculenta

Three gamma-glutamyltranspeptidase (enzymes I, II and III) were partially purified from the cell free extracts of the cultured mycelia of Morchella esculenta Fr. The molecular masses of enzymes were 155,000 (I), 219,000 (II) and 102,000 (III). All of them catalyzed both hydrolysis and transpeptidation of various gamma-glutamyl compounds. gamma-L-Glutamyl-cis-3-amino-L-proline occurring in the cultured mycelia of this fungus was a good substrate for both reactions. Km values for hydrolysis were in the order of 10(-4) to 10(-5) M, and those for transpeptidation were in the order of 10(-2) to 10(-4) M. The enzymes were inhibited by a gamma-glutamyltranspeptidase inhibitor, L-serine plus borate.

Growth, pigmentation, and expression of the puf and puc operons in a light-responding-repressor (SPB)-disrupted Rhodobacter sphaeroides

We previously cloned a trans-repressor, SPB, for the puf operon of Rhodobacter sphaeroides (Shimada et al. 1996) and revealed that SPB was a putative genetic counterpart to HvrA in Rhodobacter capsulatus, a trans-activator for the puf and puh operons (Mizoguchi et al. 1997). In this study we constructed a spb-disrupted R. sphaeroides, strain L-7, to elucidate the function of SPB. This disruption of the spb gene increased the photosynthetic growth rate and the cellular levels of photopigments under low-intensity light conditions. The disruption also derepressed the expression of the puf and puc operons under high-intensity light conditions. In strain L-7, however, strong illumination still reduced the cellular levels of photopigments as it did in the wild strain, suggesting that SPB did not directly affect the formation of photopigments. These results support our previous suggestion that SPB functions as a high-light repressor for puf operon in R. sphaeroides in striking contrast to HvrA, which is a low-light activator for puf and puh operons in R. capsulatus, even though SPB and HvrA are highly homologous. Disruption of spb gene had no effect on the oxygen-mediated regulation of the pigmentation or the expression of puf and puc operons.

Effects of DQ-2511 on neutral activity in afferent and efferent loops of gastric vago-vagal reflex pathways in the rat

1. DQ-2511 is a new substituted benzamide compound that has gastric prokinetic properties. Actions of the drug on neural discharge in the innervation of the stomach of anaesthetized rats were studied. Standard extracellular methods of multi-unit recording were used to study rates of firing in afferent and efferent filaments teased from gastric branches of the vague nerve. 2. Decreased firing in gastric vagal efferents was associated with increased rates of discharge in the gastric afferents. 3. Intravenous application of DQ-2511 resulted in increased frequency of firing in the efferents in association with decreased rate of discharge in afferent fibres. 4. Application of cholecystokinin octapeptide (CCK8) suppressed activity in the gastric efferents which occurred coincident with the elevated discharge in the afferents. Pretreatment with DQ-2511 blocked the actions of CCK8. 5. The results suggest that the gastric prokinetic action of DQ-2511 may involve suppression of activation of afferents in the sensory component of gastric inhibitory vago-vagal reflex pathways.

Possible mechanisms underlying the suppression of gastric vagal afferents due to ecabapide (DQ-2511), a gastroprokinetic agent, in rats

We examined the implication of a nitric oxide (NO)-guanosine 3',5'-cyclic monophosphate (cGMP) cascade in the suppression of gastric vagal afferents due to ecabapide in anesthetized rats using a standard extracellular method of multi-unit recording. Sodium nitroprusside (SNP, 0.5 mg/kg), an NO donor, depressed the afferent discharge rate of the vagus nerve, like ecabapide (60 micrograms/kg). On the other hand, NG-nitro-L-arginine (L-NNA, 5 mg/kg), an NO biosynthesis inhibitor, significantly elevated its discharge rate. Pretreatment with L-NNA completely blocked the action of ecabapide. Atropine (0.05 mg/kg), a competitive antagonist of muscarinic cholinoceptors, showed no effect on the afferent firing. These results suggest that ecabapide may suppress the activation of vagal afferents in gastric inhibitory vago-vagal reflex pathways through the NO-cGMP cascade.

Effects of nefiracetam, DM-9384 on amnesia and decrease in choline acetyltransferase activity induced by cycloheximide

The effects of nefiracetam, [N-(2,6-dimethyl-phenyl)-2-(2-oxo-pyrrolidinyl)acetamide, DM-9384], a cyclic derivative of GABA, were investigated in the cycloheximide (CXM)-induced amnesia animal model using the passive avoidance task. Pre-training administration of DM-9384 attenuated the CXM-induced amnesia as indicated by prolongation of step-down latency. It protected against CXM-induced inhibition of choline acetyltransferase activity in the cerebral cortex. These results suggest that DM-9384 attenuates CXM-induced amnesia by interacting with AChergic neuronal system and enhancing protein synthesis in the brain.

Beef liver glutamate dehydrogenase: a study of the oxidation of various alternative amino acid substrates retaining the correct spacing of the two carboxylate groups

1. Several glutamate analogues substituted at the beta- or gamma-carbon atoms have been tested as substrates for glutamate dehydrogenase. 2. The two gamma-methyl derivatives and DL-beta-methylglutamate give the same pH optimum (8.7) as L-glutamate, but show inhibition by ADP and activation by GTP as pH 8, unlike glutamate and like the monocarboxylic substrate L-norvaline, which gives a pH optimum of 10. 3. L-gamma-methyleneglutamate, the poorest substrate tested (0.28% of rate with glutamate) gives a high pH optimum (10), like norvaline, but shows marked activation by both ADP (13-fold) and GTP (27-fold). 4. Despite the correct dicarboxylate spacing, all the analogues were much poorer substrates than L-norvaline.

Clinical bitterness masking test for phantogeusia

It is difficult to determine the reason why a patient complains of a bitter taste when their mouth is empty. We examined a new diagnostic test using a bitterness masking substance. The bitterness masking substance, 'Benecoat BMI-60' (hereafter BMI-60), is a masking substance specific to the taste cells' bitterness receptors. After patients gargled with BMI-60 solutions, the phantom sensation of bitterness was masked in some patients, but was not masked in others. Bitter substances in saliva seemed to be masked by BMI-60, but bitterness did not seem to be masked when the locus of the phantom sensation was within the peripheral nerve and/or the brain. The bitterness masking test is useful for diagnosis of the phantom sensation of bitter taste.

Comparative evaluation of DQ-2511, a novel gastroprokinetic agent, with cisapride in ameliorative action on experimentally induced delayed gastric emptying

We compared the main pharmacological effect of DQ-2511 (3-[[[2-(3,4-dimethoxyphenyl)- ethyl]carbamoyl]methyl]amino-N-methylbenzamide), a novel gastroprokinetic agent, with that of cisapride. Single oral administration of DQ-2511 (3-10 mg kg-1) caused similar significant improvements to delays in gastric emptying of semi-solid meals evoked by cholecystokinin-octapeptide (CCK8: 5 micrograms kg-1, i.v.) in monkeys, to that with cisapride (3 mg kg-1). A 2-week oral treatment of unilaterally vagotomized rats with DQ-2511 (1-10 mg kg-1) lessened delays in gastric emptying, whereas cisapride (0.3-10 mg kg-1) had no effect under the same experimental protocols. In anesthetized rats, bolus intravenous injection of either compound (60 micrograms kg-1) enhanced gastric motility determined by means of strain gauge force transducers. Electrophysiological investigations revealed that bolus injection of DQ-2511 (6-60 micrograms kg-1) depressed the afferent discharge rate of the ventral gastric branch of the vagus nerve, while cisapride showed no effect. These results suggest that the mechanism of ameliorative action of DQ-2511 on delayed gastric emptying may differ from that of cisapride.

Dependence of sonoluminescence intensity on the geometrical configuration of a reactor cell

Dependence of sonoluminescence (SL) intensity on the geometrical configuration of a reactor cell is studied theoretically and experimentally. The model is a rectangular glass cell set in a water-cooling bath. Ultrasound is irradiated from the bottom of bath into the cell. Theoretical analysis of transmitted acoustic energy assuming a plane acoustic wave clarified the influences of distance between the transducer and the cell bottom, thickness of the cell bottom, and water depth in the cell. The theory is examined through intensity measurement of SL emitted in the cell using a photomultiplier tube. Dependence of SL intensity on the above parameters agreed with the theory very well. Distributions of SL are also observed using a high sensitive CCD camera and are compared with optically visualized sound fields to show the relationship between the sound field and the SL.

DQ-2511, having an antiulcer action, elicits vasodilation through an increase in cyclic GMP contents in rat arteries

It has been reported that 3-(([2-(3,4-dimethoxyphenyl)ethyl]carbamoyl)methyl)amino-N-methylbenz amide (DQ-2511: ecabapide) effectively increases gastric mucosal blood flow in rats, suggesting that this property may contribute to the antiulcer activity. To clarify the mechanisms underlying the increase in gastric mucosal blood flow, we investigated the dilator response of rat isolated thoracic aorta, mesenteric artery and celiac artery smooth muscle preparations to DQ-2511. This compound prevented noradrenaline-induced contraction in both the presence and absence of endothelium in the arterial specimen, and it (0.01-1 mM) inhibited these contractions induced by noradrenaline in all tissues in a concentration-dependent manner. This inhibitory effect of DQ-2511 was most evident in the celiac artery. The dilator response to DQ-2511 (0.1 mM) was abolished after pretreatment with methylene blue (3 microM), a guanylate cyclase inhibitor. Under the same conditions, methylene blue inhibited the dilator response to acetylcholine (1 microM), but not that to papaverine (10 microM). Furthermore, when DQ-2511 (0.01-1 mM) was incubated with the arterial preparations, this compound increased cyclic GMP content in segments in a concentration-dependent manner. These findings demonstrate that the vasodilation induced by DQ-2511 is independent of the endothelium and is related to the augmentation of intracellular cyclic GMP content, which may consequently contribute to the increased gastric mucosal blood flow.

Apocrine adenocarcinoma of the bilateral axillae

A case of apocrine adenocarcinoma arising in the bilateral axillae is reported. The patient was an 88-year-old Japanese male who complained of a mass lesion and pus-like discharge in the right axilla. Another mass was also noticed in the left axilla. No other neoplastic lesion was found in other sites of the body. The histologic appearances of the bilateral axillary tumors were almost identical. Both were adenocarcinoma with varying degrees of differentiation, composed of glands and nests of atypical epithelial cells with abundant eosinophilic cytoplasm. Some neoplastic cells exhibited cytoplasmic projections on their apical surface. Foci of in situ carcinoma were observed within the neoplastic tissue in the bilateral axillae. The neoplastic cells were immunohistochemically positive for epithelial membrane antigen (EMA) and gross cystic disease fluid protein (GCDFP-15), but negative for carcinoembryonic antigen (CEA). On the basis of their histologic and immunohistochemical features and distinctive location, the tumors were diagnosed as apocrine adenocarcinoma.

Detection of tumor-inducing plasmid DNA sequence in Agrobacterium tumefaciens by DNA-DNA hybridization

Absence of plasmid DNA sequences in non-tumorigenic (crown gall tumor) strains of Agrobacterium tumefaciens was confirmed by DNA-DNA hybridization between purified tumor-inducing (Ti) plasmid DNAs isolated from the progenitor tumorigenic strains and 3H-labeled whole cell DNAs from tumorigenic strains and their non-tumorigenic derivatives. The genes controlling tumorigenicity in plant and utilizability of nopaline as their sole nitrogen source were confirmed to locate on Ti-plasmids.

Crystallization and preliminary X-ray crystallographic analysis of UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase (VvGT5) from the grapevine Vitis vinifera

Grapevine (Vitis vinifera) glycosyltransferase 5 (VvGT5) is a UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase that catalyses the 3-O-specific glucuronosylation of flavonols using UDP-glucuronic acid as a sugar donor to produce flavonol 3-O-glucosides, which are important bioactive phytochemicals. Recombinant VvGT5 expressed in Escherichia coli cells was purified and crystallized by the sitting-drop vapour-diffusion method. A full set of X-ray diffraction data was collected to 2.2 Å Bragg spacing from a single crystal using a synchrotron-radiation source. The crystal was hexagonal, belonging to space group P6(1)22, with unit-cell parameters a = b = 102.70, c = 535.92 Å. The initial phases were determined by the molecular-replacement method.