Activation of prostaglandin E2-receptor EP2 and EP4 pathways induces growth inhibition in human gastric carcinoma cell lines

The effect of prostaglandin E2 (PGE2) on the proliferation of gastric cancer cells is still unclear. PGE2 receptors are divided into four subtypes - EP1, EP2, EP3, and EP4 - which are coupled to three different intracellular signal-transduction systems. Stimulation of EP2 and EP4 is linked with cyclic adenosine 3', 5'-monophosphate (cAMP)-dependent protein kinase A (PKA). In some human gastric cancer cells, PGE2 has been suggested to have an antiproliferative effect by way of increased cAMP production. Expression of EP2 and EP4 in human gastric carcinoma cells, however, has not been examined. We examined the expression of EP2 and EP4 and the antiproliferative effects of specific EP2 and EP4 agonists on four different human gastric cancer cell lines. Our data clarified that all the cell lines investigated in this study expressed EP2 and EP4 and that the specific agonists of these receptors induced growth inhibition with an accompanying increase in cAMP production. In summary, gastric cancer cells have EP2 and EP4 receptors, and their selective activation is linked with the decreased cell proliferation.

Pharmacological effect of amezinium on urethra and bladder of rabbits

The pharmacological effect of amezinium on the urethra and bladder of rabbits was investigated. Amezinium produced concentration-dependent contractions in isolated urethral strips. The maximum response was approximately 30% of that caused by norepinephrine (NE). The concentration-response curve of NE was shifted to the left by amezinium. Moreover, amezinium enhanced the relaxative effect of NE on carbachol-induced contractions in isolated bladder strips. In anesthetized rabbits, amezinium significantly increased the intraurethral pressure (IUP) but produced only slight increases in mean blood pressure (MBP). Pre-treatment with amezinium ehhanced NE-induced increases in IUP index and MBP. The enhancing effect on the IUP index lasted much longer than that on MBP. In a stress incontinence model amezinium significantly inhibited the incontinence after an i.v. infusion of a low dose of NE. This effect was antagonized by pre-treatment with prazosin. These results suggest that amezinium may produce an excellent effect for stress incontinence, especially mixed, without severe adverse events such as sudden hypertension.

DNA diversity of the wla gene cluster among serotype HS:19 and non-HS:19 Campylobacter jejuni strains

Campylobacter jejuni infection is an important trigger of Guillain-Barré syndrome (GBS), and serotype HS:19 strains are over-represented among GBS-associated isolates. Structures in C. jejuni lipooligosaccharide (LOS) resemble human gangliosides, suggesting that molecular mimicry could be important in triggering the neural injury. We assessed the genetic diversity among 36 C. jejuni serotype HS:19 and non-HS:19 strains by analysis of PCR-based restriction fragment length polymorphism (RFLP) patterns of 12 LOS biosynthesis-related genes (wla cluster). PCR amplification revealed that the size, order, and direction of each wla gene was identical among all strains tested. However, an additional ORF, located between wlaI and wlaK, was detected in 28 of the 36 isolates examined, and nucleotide sequence analysis revealed that the gene was identical to orfE in C. jejuni strain NCTC 11168. An inverted repeat motif was found downstream of the wlaI stop codon and upstream of the orfE stop codon, an organization allowing pairing of repeated sequences that could lead to deletion of the internal segment. Digestion of the PCR products with restriction endonuclease DdeI or AluI and cluster analysis of RFLP banding patterns showed that all HS:19 strains were closely related and distinct from non-HS:19 strains, consistent with earlier analyses, suggesting that HS:19 strains represent a highly clonal population. RFLP analysis of wla genes also may be useful for epidemiological studies.

Effects of recombinant bovine interferon gamma on Strongyloides papillosus infection in calves

The effects of interferon (IFN) gamma on the course of infection with Strongyloides papillosus in calves were investigated. Calves (N = 7 each) were inoculated with recombinant bovine IFNy or control solution daily from day 0 to day 15 following S. papillosus infection. Treatment with IFN-gamma induced an increase in faecal egg output in the peak stage of infection. The IFNgamma-treated animals harboured more worms, especially more immature worms, in the small intestine than control animals at necropsy on day 17, with no decreases in intestinal mucosal mast cells. Both animal groups had similar small numbers of intestinal worms at necropsy on day 26. All control animals developed peripheral blood eosinophilia on day 7, while five of seven IFN-gamma-treated animals did not. Serum alpha1-acid glycoprotein concentrations increased on day 7 in both animal groups, with higher values in control animals than in IFNgamma-treated animals. Control animals mounted a predominant IgG1 response to S. papillosus from day 10, while IFNgamma-treated animals did from day 22. These data suggested that IFNgamma inhibited some host protective responses to S. papillosus migrating larvae, resulting in an improvement of worm survival after a period when protective responses should be activated during the early stage of infection. The effects of IFNgamma on intestinal worm expulsion should be confirmed by further experiments.

Development of a combined filtration-enrichment culture followed by a one-step duplex PCR technique for the rapid detection of Campylobacter jejuni and C. coli in human faecal samples

A new combined filtration-enrichment culture followed by a PCR technique for the rapid detection of Campylobacterjejuni and C. coli in human faeces has been developed. Only bacteria that passed through the membrane could multiply in the enrichment culture; target bacteria were detected by a one-step duplex PCR technique with combinations of primers that are specific for different Campylobacter spp., which should allow for the detection of a mixed infection in a single patient. A Falcon cell-culture insert and 24-well tissue-culture plates were used. After 2 days, both C. jejuni and C. coli were reliably detected in diluted faeces that were seeded with as few as 10 cells which corresponds to a concentration of 10(3) cfu/g. Even allowing for the dilution of faecal samples, this represents an increase in sensitivity of two-to-three orders of magnitude over the conventional filtration method.

T cell-mediated cytotoxicity via Fas/Fas ligand signaling in Helicobacter pylori-infected gastric corpus

BACKGROUND

Helicobacter pylori infection induces T helper-1 immune responses in inflamed mucosa. However, the role of T cell-mediated cytotoxicity in the induction of epithelial apoptosis is still unclear. The aim of this study was to investigate the involvement of the Fas/Fas ligand (Fas/Fas-L) system in the H. pylori-infected gastric corpus.

MATERIALS AND METHODS

Gastric fundic biopsy specimens were taken from patients with and without H. pylori infection. The expression of Fas and Fas-L was examined by immunohistochemistry and RT-PCR. Subsets of gastric infiltrating T cells in the biopsy specimens were studied by immunohistochemistry and flow cytometry. In histological sections, apoptosis was detected by the TUNEL method. We studied the in vitro expression of Fas-L in peripheral T cells after stimulation with H. pylori antigen and interferon-gamma (IFN-gamma). The Fas-mediated in vitro cytotoxicity of activated T cells was assessed by flow cytometry.

RESULTS

The numbers of CD4+ and CD8+ T cells were greater in H. pylori-infected subjects. Fas expression was abundantly increased on fundic gland epithelium, and Fas-L was detected on lamina propria mononuclear cells in H. pylori-infected mucosa. TUNEL-positive epithelial cells were also increased in H. pylori-infected subjects. H. pylori antigen and IFN-gamma induced Fas-L mRNA expression in both CD4+ and CD8+ T cells. In cytotoxic assay, activated T cells induced apoptosis in AGS cells, which could be significantly inhibited by neutralizing Fas-L antibody.

CONCLUSIONS

T cell-mediated cytotoxicity via Fas/Fas-L signaling may contribute to the induction of apoptosis in gastric epithelial cells during H. pylori infection.

Complete genomic sequence of the filamentous nitrogen-fixing cyanobacterium Anabaena sp. strain PCC 7120

The nucleotide sequence of the entire genome of a filamentous cyanobacterium, Anabaena sp. strain PCC 7120, was determined. The genome of Anabaena consisted of a single chromosome (6,413,771 bp) and six plasmids, designated pCC7120alpha (408,101 bp), pCC7120beta (186,614 bp), pCC7120gamma (101,965 bp), pCC7120delta (55,414 bp), pCC7120epsilon (40,340 bp), and pCC7120zeta (5,584 bp). The chromosome bears 5368 potential protein-encoding genes, four sets of rRNA genes, 48 tRNA genes representing 42 tRNA species, and 4 genes for small structural RNAs. The predicted products of 45% of the potential protein-encoding genes showed sequence similarity to known and predicted proteins of known function, and 27% to translated products of hypothetical genes. The remaining 28% lacked significant similarity to genes for known and predicted proteins in the public DNA databases. More than 60 genes involved in various processes of heterocyst formation and nitrogen fixation were assigned to the chromosome based on their similarity to the reported genes. One hundred and ninety-five genes coding for components of two-component signal transduction systems, nearly 2.5 times as many as those in Synechocystis sp. PCC 6803, were identified on the chromosome. Only 37% of the Anabaena genes showed significant sequence similarity to those of Synechocystis, indicating a high degree of divergence of the gene information between the two cyanobacterial strains.

Functional expression of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors precedes the development of cholinergic phenotype in embryonic rat septal cells in culture

We examined the development of cholinergic neuronal functions and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) responses in cultured embryonic rat septal cells. Choline acetyltransferase activity was increased from 4 to 6 days in culture and reached a plateau at day 8. Acetylcholine release was increased from 6 to 8 days in culture. AMPA-induced increase in intracellular Ca(2+) level was observed at 3 days in culture and most of the AMPA-responsive cells coincided with high-K(+) responsive cells. These results suggest that cholinergic neurons develop their neuronal functions about 8 days under cultured conditions, and functional expression of AMPA receptors precedes the cholinergic functional development.

p21Cip-1/SDI-1/WAF-1 gene is involved in chondrogenic differentiation of ATDC5 cells in vitro

Development of skeletal cartilage is characterized with coupling growth arrest and cell differentiation. Here, to understand the cyclin-dependent kinase inhibitors involved in the progression of chondrogenic differentiation, we examined changes in the expression levels of cyclin-dependent kinase inhibitor members using mouse ATDC5 prechondrocytes as a widely used in vitro model of cartilage differentiation. Up-regulation of p21 and p27 mRNA was observed following a decrease in growth rate of prechondrocytes, and both transcripts subsequently accumulated during chondrogenic differentiation; p15, p18, and p19 mRNA, in contrast, did not change during differentiation. Only the up-regulation of p21 mRNA during differentiation was prevented by the continuous treatment of early chondrogenic inhibitor, parathyroid hormone, indicating a close correlation between differentiation and p21 induction in ATDC5 cells. Therefore, to examine the role of p21 during chondrogenesis, we established stable cell lines overexpressing full-length p21 antisense RNA in ATDC5. The reduction of endogenous p21 in these cell lines caused inhibition of early chondrogenic differentiation in ATDC5, indicating that p21 gene plays an important role in this process of the cells in vitro. Furthermore, the level of p21 protein and p21.CDK2 complexes transiently increased during differentiation, but not in undifferentiated cells, leading to a decrease in CDK2-associated kinase. However, differentiation-dependent expressed p21 protein was degraded by a proteasome-dependent pathway. Thus, the progression of chondrogenic differentiation requires down-regulation of CDK2-associated kinase with an increase in p21 protein and subsequent degradation of this protein by a proteasomal pathway.

Effects of AH-9700, (+)-pentazocine, DTG and oxybutynin on micturition in anesthetized rats with acetone-induced cystitis

We investigated the effects of AH-9700 (1-[2-(3,4-dihydro-6,7-dimethyl-2-naphthalenyl)ethyl] pyrrolidine fumarate; a novel sigma receptor ligand), (+)-pentazocine and 1,3-di-o-tolylguanidine (DTG) (two typical sigma receptor ligands), and oxybutynin (a currently used anti-pollakiuria drug) on cystometrograms in anesthetized rats with 30% acetone-induced cystitis. Compared to sham-treated rats, acetone-treated cystitis models exhibited an increase in urinary frequency during continuous filling cystometry. Intravenous administration of AH-9700 (1-5 mg/kg), (+)-pentazocine or DTG to the rats with cystitis dose-dependently prolonged micturition intervals and increased the micturition threshold pressure. Oxybutynin (1 mg/kg. i.v.) also extended micturition intervals, but decreased the micturition pressure. These results indicate that AH-9700, (+)-pentazocine and DTG improve abnormal frequent urination caused by acetone-induced cystitis in a manner different from that of oxybutynin.

Decreased acetylcholine content and choline acetyltransferase mRNA expression in circulating mononuclear leukocytes and lymphoid organs of the spontaneously hypertensive rat

It has been confirmed that the neurotransmitter acetylcholine (ACh) is present in blood; it is synthesized in T-lymphocytes by choline acetyltransferase (ChAT) and released upon T-lymphocyte activation. Both muscarinic and nicotinic ACh receptors have been identified on lymphocytes isolated from thymus, lymph node, spleen and blood, and their stimulation by muscarinic and nicotinic agonists elicits a variety of functional and biochemical effects, providing a strong argument that ACh synthesized and released from T-lymphocytes acts as an autocrine and/or paracrine factor regulating immune function. In the present study, we compared ACh levels in the blood, circulating mononuclear leukocytes (MNLs), thymus and spleen of spontaneously hypertensive rats (SHRs), which exhibit immune deficiencies related to the emergence of natural thymocytotoxic autoantibody, age-related decline of T-cell function and morphological changes in immune organs, with ACh levels in age-matched, normotensive Wistar Kyoto rats. In each case, ACh levels in 5-, 10- and 20-week-old SHRs were significantly lower than in WKYs. ChAT mRNA expression in MNLs was also significantly depressed in the SHRs. These results suggest that diminished synthesis and release of ACh from MNLs into blood and lymphoid organs likely reflects an immune deficiency related to T-cell dysfunction.

Posttreatment nadir M-protein level is a stronger discriminator of survival following plateau attainment than is percent reduction in M-protein in patients with IgG myeloma

We conducted a retrospective study of patients with IgG or IgA myeloma who attained plateau to evaluate the relationships between survival and posttreatment nadir M-protein levels and between survival and the response to treatment evaluated by the percent reduction in M-protein. Of the 127 patients comprising 92 IgG and 35 IgA myeloma patients with disease stages II or III, 51 (40.2%) attained plateau. For IgG myeloma patients who attained plateau, survival time was not affected by the percent reduction in M-protein (median survival, 59.5 months for responding patients versus 54.4 months for nonresponding patients, P = .6910). Posttreatment nadir M-protein level, however, did affect survival time (median survival, 61.2 months for <3000 mg/dL versus 25.7 months for >3000 mg/dL, P = .0439). These findings suggest that the posttreatment nadir M-protein level is a stronger discriminator of survival following plateau attainment than the percent reduction of M-protein in patients with IgG myeloma.

Radiographic evaluation of malignant fibrous histiocytoma affecting maxillary alveolar bone: a report of 2 cases

OBJECTIVE

The purpose of this study was to evaluate the radiographic findings of malignant fibrous histiocytoma (MFH) and to discuss the contribution of these findings to a differentiation of MFH from other malignant tumors of the head and neck.

STUDY DESIGN

Two cases of MFH of the maxillary sinus affecting the alveolar bone were evaluated radiographically and scintigraphically.

RESULTS

We reported the following findings, which have only seldom been described: the presence of fairly well-demarcated bone destruction in the intraoral radiograph; the relatively smooth surface, uniform density, or no necrotic area of the tumor; in computed tomograph images showing the clear separation of the tumor from surrounding soft tissues; bone scintigraphs reflecting the periosteal reaction to tumor invasion; and lymphoscintigraphy of the metastatic lymph nodes.

CONCLUSION

We evaluated the radiographic findings from 2 cases of MFH and describe findings that may aid in the differentiation of MFH. These radiographic features may help dentists differentiate MFH from other malignant tumors in the head and neck, although MFH is a rare disease and there are no radiographic findings that would indicate a specific diagnosis of MFH.

Peroxisome proliferator-activated receptor gamma ligand-induced growth inhibition of human hepatocellular carcinoma

Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands have been implicated in the growth inhibition and differentiation of certain human cancers with diverse tissue origin. In this study, expression of PPARgamma in human hepatocellular carcinoma (HCC) and the effect of PPARgamma ligands on HCC cells were investigated in vitro using Hep G2, HuH-7, KYN-1 and KYN-2 cell lines. All cell lines were found to express functionally active PPARgamma and a marked growth inhibition was induced by thiazolidinedione ligands troglitazone, and pioglitazone as well as with its natural ligand 15-deoxy-Delta(12,14)-prostaglandin J(2). The growth inhibitory effect was associated with a dose-dependent inhibition of DNA synthesis, cell cycle progression and alpha fetoprotein expression.

Glucocorticoid treatment increases inhibitory m(2) muscarinic receptor expression and function in the airways

M(2) muscarinic receptors on parasympathetic nerve endings inhibit acetylcholine release in the airways. In this study, the effects of dexamethasone on M(2) receptors in vivo and in primary cultures of airway parasympathetic neurons were tested. Treating guinea pigs with dexamethasone (0.1 mg/kg, daily for 2 d) substantially increased inhibitory M(2) muscarinic receptor function, decreasing airway responsiveness to electrical stimulation of the vagi. At the same time, dexamethasone decreased the response to acetylcholine but not to methacholine, suggesting that cholinesterase activity was increased. When both cholinesterase and M(2) receptors were blocked (using physostigmine and gallamine, respectively) vagally induced bronchoconstriction was increased to control values. In primary cultures of airway parasympathetic neurons, dexamethasone significantly decreased the release of acetylcholine in response to electrical stimulation. Blocking inhibitory M(2) receptors using atropine (10(-5) M) increased acetylcholine release. After the M(2) receptors were blocked there was no difference in acetylcholine release between control and dexamethasone-treated cultures. M(2) receptor gene expression was increased by more than fivefold in dexamethasone-treated cultures. Immunostaining of dexamethasone-treated neurons demonstrated more intense staining. Thus, decreased vagally mediated reflex bronchoconstriction after glucocorticoid treatment may be the result on increased M(2) receptor expression and function as well as increased degradation of acetylcholine by cholinesterase.

Effect of bicozamycin on the eradication of Shiga toxin-producing Escherichia coli in calves

Fifty-nine calves, aged 11 days to 9 months, from three farms breeding Japanese Black beef cattle in Miyazaki Prefecture, Japan, were examined for the presence of Shiga toxin-producing Escherichia coli (STEC). A high prevalence of STEC was detected among calves, with 45 (76.3%) animals carrying STEC including different serogroups (O26, O74, O111, O114, O119, O127, O153, O157, and ONT) and toxin types. The number of STEC in the feces was estimated by a combined method involving enumeration of colony-forming units by a plate-most-probable-number (plate-MPN) technique and polymerase chain reaction for the detection of Shiga toxin genes. Fecal shedding ranged from 10(1) to 10(10) MPN/g feces. To evaluate the safety and efficacy of bicozamycin (BCM: previously named as bicyclomycin) in eradicating STEC, 30 calves carrying STEC with or without diarrhea were examined. Fifteen calves were treated orally with BCM (10 mg/kg/day) once daily for 5 days, and the other 15 were untreated. Twenty-four hours after the last dose, fecal specimens were collected from both groups to compare the number of coliforms and STEC with those before treatment. BCM-treated animals had a significantly lower number of coliforms and STEC compared to the untreated calves. The STEC eradication rate was 86.6% (13/15) in the BCM-treated group, compared to 0% (0/15) in the control group. The corresponding cure rates for diarrhea were 87.5 (7/8) and 0% (0/3), respectively. No adverse reactions were observed in the calves during treatment. It is concluded that BCM is an effective agent for the eradication of STEC in calves with or without diarrhea.

Experimental transmission of sheep-associated malignant catarrhal fever from sheep to Japanese deer (Cervus nippon) and cattle

The assumption that sheep carry ovine herpesvirus-2 (OvHV-2), the causative agent of sheep-associated malignant catarrhal fever (SA-MCF), is widely accepted, albeit OvHV-2 has not been isolated. We attempted experimental contact transmission of MCF from Japanese sheep persistently infected with OvHV-2 to Japanese deer (Cervus nippon) and cattle. In Experiment 1, a deer was kept in close quarters with an infected ewe. In Experiment 2, a second deer was kept with the same ewe. In Experiment 3, two cows were each kept with two infected wethers. In Experiment 1, the deer developed clinical signs at 138 days after first contact and then died. OvHV-2 genes by polymerase chain reaction (PCR) and fluorescent antibodies to Alcelaphine herpesvirus-1 were detected in the affected deer. Moreover, sequences of PCR products (423bp), obtained by amplification of materials from the sheep and from the affected deer, coincided. These results clearly confirmed that the sheep was a carrier of OvHV-2, and that this virus had induced SA-MCF in a deer. In other experiments, no OvHV-2 infection occurred in deer and cattle during the 6-18 months periods of contact, though viral genes were detected in the nasal swabs and white blood cells of the sheep. To our knowledge, this is the first report on successful experimental transmission of MCF from OvHV-2-infected sheep to deer.

Analysis of gastrin receptor gene expression in proliferating cells in the neck zone of gastric fundic glands using laser capture microdissection

Gastrin stimulates proliferation of progenitor cells in the neck zone of gastric fundic mucosa. However, whether it directly enhances this proliferation through its receptors remains unclear. We investigated the expression of gastrin receptors in neck zone proliferating cells in rat gastric fundic glands using a reverse transcription polymerase chain reaction (RT-PCR) coupled with laser capture microdissection and in situ RT-PCR. Gastrin receptor expression was identified in c-fos-expressing cells located in the neck zone, and results of the RT-PCR analysis argued against contamination by other cells, such as enterochromaffin-like, parietal or D cells. Supporting this finding, gastrin receptor gene expression was identified in the neck zone as well as base glands by in situ RT-PCR. Therefore, it is suggested that proliferating cells in the neck zone are stimulated directly by gastrin via their gastrin receptors.

[A breast cancer patient with recurrence in the thoracic wall in whom a high-dose of toremifene was effective]

The patient was a 53-year-old female who presented with a primary complaint of reddening of the left precordial skin. She had undergone mastectomy for cancer of the left breast 12 years and 4 months earlier and had received endocrine chemotherapy including TAM as a postoperative adjuvant therapy. A diagnosis of thoracic wall recurrence was made by chest CT and pathological examination of skin biopsy specimens. Toremifene (TOR) was administrated at 120 mg/day, and PR was maintained for 8 months. Even after the condition became PD, the patient has retained adequate QOL with combination therapies including radiotherapy, and is still treated on an outpatient basis 3 years after the beginning of the treatment.

Two types of pea leghemoglobin genes showing different O2-binding affinities and distinct patterns of spatial expression in nodules

Five distinct cDNA clones for leghemoglobin (Lb) were isolated from pea (Pisum sativum) nodules. They were classified into two groups designated PsLbA and PsLbB according to sequence homology, O(2)-binding affinities of the recombinant proteins, and in situ localization of the mRNAs. The PsLbB group was comprised of four cDNA clones: PsLb120-1, -8, -29, and -34. They showed a high similarity of deduced amino acid sequences and O(2)-binding affinities of their recombinant proteins. Among them, the spatial expression pattern of PsLb120-1 was investigated in great detail, indicating that its transcripts were localized in the region from infection zone II to the distal part of nitrogen fixation zone III in effective nodules. PsLb5-10, which is the only cDNA clone of the PsLbA type, differed considerably from the PsLbB type in amino acid sequence, and the recombinant protein had a higher O(2)-binding affinity than those of the PsLbB type. The transcripts of PsLb5-10 were detected throughout the central tissue of effective nodules. However, in ineffective nodules on the pea mutant E135 (sym13), transcripts of PsLb5-10 were restricted to the distal portion of the central tissue as well as those of PsLb120-1. These findings indicate that the pea genome contains two types of Lb genes and suggest that they have different roles in the development of nitrogen-fixing symbiosis in pea nodules.

Pharmacological actions of AH-9700 on micturition reflex in anesthetized rats

In radioligand binding assays, AH-9700 (1-[2-(3,4-dihydro-6,7-dimethyl-2-naphthalenyl)ethyl]pyrrolidine fumarate) had high affinity for sigma receptors and moderate affinity for muscarinic receptors. The affinity of AH-9700 for sigma(1) receptors was significantly reduced in the presence of 5'-guanylyl-imidodiphosphate (GppNHp). In isolated bladder strips of rats, AH-9700 inhibited carbachol-induced contractions. In anesthetized rats, i.v. administration of AH-9700 and typical sigma receptor ligands, (+)-pentazocine and 1,3-di-o-tolylguanidine (DTG), but not oxybutynin, dose-dependently inhibited rhythmic isovolumetric reflex bladder contractions. AH-9700 and oxybutynin suppressed the amplitude of rhythmic bladder contractions. On the other hand, at doses lower than used i.v., the i.c.v. administration of AH-9700 or the sigma receptor ligands inhibited rhythmic bladder contractions without suppressing the amplitude. This inhibitory effect of AH-9700 was markedly reduced by pretreatment with i.c.v. pertussis toxin. These results suggest that AH-9700 exerts a marked anti-micturition reflex effect through central sigma receptors possibly related to pertussis toxin-sensitive Gi/o-proteins and a moderate spasmolytic effect based on its peripheral anti-muscarinic activity.

Non-neuronal neurotransmitters and neurotrophic factors in amniotic epithelial cells: expression and function in humans and monkey

Human amniotic epithelial cells (HAEC) are formed from epiblasts on the 8th day after fertilization. Because they lack major histocompatibility complex (MHC) antigen, human amniotic tissue transplantation has been used for allotranplantation to treat patients with lysosomal diseases. We have provided evidence that HAEC have multiple functions such as synthesis and release of acetylcholine (ACh) and catecholamine (CA) as well as expressing mRNA coding for dopamine receptors and dopamine (DA) transporter (DAT). On the other hand, we showed that monkey amniotic epithelial cells (MAEC) synthesize and release CA and posses DA receptors and DAT. Detection of muscarinic actylcholine receptors indicates the presence of an autocrine mechanism in HAEC. Recently, we found that HAEC have neurotrophic function in conditioned medium from HAEC, indicating the presence of a novel neurotrohpic factor that is synthesized and released from HAEC. The amniotic membrane may have a significant role in supplying neurotrophic factors as well as neurotransmitters to the amniotic fluid, suggesting an important function in the early stages of neural development of the embryo. This review will focus on the neuropharmacological aspects of HAEC and MAEC in relation to the physiology of amniotic membrane.

Predominance of G3B and G14 equine group A rotaviruses of a single VP4 serotype in Japan

A total of 65 equine group A rotaviruses (GAR) isolated from diarrheal foals at 48 farms in Hokkaido, Japan, between 1996 (29 isolates) and 1997 (36 isolates) were characterized for their VP7 and VP4 serotypes by PCR, nucleotide sequencing, and virus neutralization (VN) tests. By PCR VP7 typing, all isolates were classified as G3 or G 14, and the predominant serotype in each year was G3 (86%) in 1996 and G14 (53%) in 1997. VN tests with these 20 isolates randomly selected confirmed the specificity of PCR on the bases of complete agreement of the results in these methods (9 G3 and 11 G14), and revealed that all 9 G3 isolates were subtype G3B. There were five differing amino acid residues in three VP7 antigenic regions between subtypes G3A and G3B. Antiserum to a baculovirus recombinant that expressed P[12] VP4 neutralized all isolates and P[12] reference strains. These results suggest that genotype P[12] GAR belong to a single VP4 serotype, and that one VP4 and two VP7 serotypes (G3B and G14) of GAR were predominant in the equine population in Japan.

An independent non-neuronal cholinergic system in lymphocytes

Acetylcholine (ACh) is a well characterized neurotransmitter occurring throughout the animal kingdom. In addition, both muscarinic and nicotinic ACh receptors have been identified on lymphocytes of various origin, and their stimulation by muscarinic or nicotinic agonists elicits a variety of functional and biochemical effects. It was thus initially postulated that the parasympathetic nervous system may play a role in modulating immune system function. However, ACh in the blood has now been localized to lymphocytes; indeed expression of choline acetyltransferase (ChAT), an ACh synthesizing enzyme, has been shown in human blood mononuclear leukocytes, human leukemic T-cell lines and rat lymphocytes. Stimulation of T-lymphocytes with phytohemagglutinin activates the lymphoid cholinergic system, as evidenced by increased synthesis and release of ACh and increased expression of mRNAs encoding ChAT and ACh receptors. The observation that M3 muscarinic receptor stimulation by ACh and other agonists increases the intracellular free Ca2+ concentration and upregulates c-fos gene expression strongly argues that ACh, synthesized and released from T-lymphocytes, acts as an autocrine and/or paracrine factor regulating immune function. These findings present a compelling picture in which immune function is, at least in part, under the control of an independent lymphoid cholinergic system.

Nonrotation of the midgut with appendiceal mucocele in an adult

Nonrotation of the midgut in adults and appendiceal mucocele are both rare pathological conditions. We report here the first case of nonrotation of the midgut associated with appendiceal mucocele. The patient was a 51-year-old man admitted to hospital with ileus. An upper gastrointestinal series and a barium enema revealed nonrotation of the midgut without midgut volvulus and with a mass in the ileocecal area. Laparotomy revealed an appendiceal mucocele adhering to the urinary bladder and the rectum. The mucocele had partly ruptured; yellowish mucinous material had entered the abdominal cavity, resulting in pseudomyxoma peritonei. Histological examination revealed a mucinous tumor of the appendix with borderline malignancy. In this patient, the ileus was caused by the appendiceal mucocele rather than being caused by nonrotation of the midgut.