Inhibition by ATP of calcium oscillations in rat cultured hippocampal neurones

1 The effect of adenosine 5'-triphosphate (ATP) on glutamatergic synaptic transmission in hippocampus was examined by an indicator of intracellular Ca2+ oscillations. These oscillations were postsynaptic responses by glutamate released from presynaptic sites. ATP completely inhibited the oscillations in a concentration-dependent manner. 2 The ATP-induced inhibition was mediated via P2-purinoceptors since ATP exhibited the inhibitory action even in the presence of P1-purinoceptor antagonists. Also non-hydrolysable ATP analogues and uridine 5'-triphosphate (UTP) inhibited the oscillation. 3 The rank order of agonist potency of ATP analogues for inhibition of the Ca2+ oscillation was as follows: 2-methyl-thio-adenosine 5'-triphosphate > or = ATP > adenosine 5'-O-(3-thiotriphosphate)>UTP> alpha, beta-methylene-adenosine 5'-triphosphate. These inhibitory effects were insensitive to suramin. Judging from this rank order of potency, the inhibitory P2-purinoceptor could be assigned to a subclass of GTP-binding protein coupled-type receptors. 4 The site of action of ATP was thought to be presynaptic since ATP did not affect the postsynaptic Ca2+ responses by glutamate. These results suggest the existence of a presynaptic inhibitory P2-receptor that inhibits glutamate release in the hippocampus.

[A case of polymyalgia rheumatica with swelling and pitting edema of the distal lower extremities]

We report a case of an 82-year-old woman with polymyalgia rheumatica (PMR) associated with swelling and pitting edema of the lower extremities. The patient had been previously admitted because of PMR in 1990, but there was no history of swollen extremities. In July 1996, at another hospital, she was again diagnosed as having PMR on the basis of pain in the neck, shoulders and lower back. Administration of prednisolone was followed by improvement of the symptoms. Four months later, similar pain recurred and swelling of the lower extremities was noted. On admission, the erythrocyte sedimentation rate was 86 mm/h, and C-reactive protein was 15.5 mg/dl. Reviewing the previous treatment, it was ascertained that her clinical deterioration was due to premature reduction of the steroid dosage. The cause of the swelling of the lower extremities was unlikely to be heart, liver, kidney or endocrine disease. Prednisolone was increased from 2.5 mg to 10 mg daily with marked improvement in all the symptoms including the swelling and pitting edema. In 1996, a study reported distal extremity swelling with pitting edema as a manifestation of PMR, which mostly developed concurrently with proximal symptoms or during relapses of PMR. The swelling responded poorly to non-steroidal antiinflammatory drugs but promptly to corticosteroids. The distal swelling was reported to be tenosynovitis and synovitis of the surrounding structures. The present case appears similar to that report. More studies of PMR need to be done.

[Effects of imagery ability and speech anxiety on imagery vividness of imaginary of speech scene]

Effects of imagery ability and speech anxiety on imagery vividness of imaginary of speech scene were examined. Subjects were divided into four groups in terms of high and low scores of Scale of Mental Imagery-Short Form (SMI-S) and a speech anxiety scale. They imagined themselves in neutral, action and speech scenes. They were asked to rate valence, arousal, and dominance of associated emotion, as well as imagery vividness, of each scene. An SMI-S effect was found on the vividness for neutral and action scenes. For vividness of the speech scene, however, speech anxiety had a stronger effect than imagery ability. The subjects with high speech anxiety significantly decreased imagery vividness, and experienced stronger arousal during imaginary speech. Good-imagery subjects with high speech anxiety reported stronger arousal than poor-imagery subjects. These results suggested that speech anxiety was a major determinant of imagery vividness of imaginary of speech scene.

Treatment of hyperthyroidism with a small single daily dose of methimazole: a prospective long-term follow-up study

A prospective long-term follow-up study was performed with conventional divided doses (group C: 10 mg 3 times daily, N = 58) and a small single daily dose (group S: 15 mg once daily, N = 54) of methimazole (MMI) for the treatment of Graves' hyperthyroidism. Within 8 weeks, almost 80% of the patients in both groups became euthyroid. The mean time required to achieve a euthyroid state was 5.6 +/- 2.7 weeks in group C and 5.8 +/- 3.1 in group S. TSH binding inhibitor immunoglobulin (TBII) levels before therapy were 44.2 +/- 22.7% and 47.1 +/- 23.9% in group C and group S, respectively. A similar gradual fall in TBII levels was observed in both groups over a two-year period of treatment. MMI doses were gradually reduced to a maintenance dose (5 mg daily) after the patients became euthyroid. The patients were treated for 28 +/- 9 months and were followed up after therapy was stopped (observation period in patients who remained in remission was 12-130 (75 +/- 34) months and the interval to relapse in recurred cases was 1-98 (20 +/- 27) months). The rates of recurrence in group C were 41% at 1 yr, 54% at 2 yrs, 56% at 4 yrs and 61% at 6 yrs. In group S, these were 44%, 53%, 56% and 63%, respectively. No differences between relapse rates were observed with the two different dosage regimens. Adverse effects occurred more frequently in group C patients (24%) than in group S patients (13%). These results show that there is no difference in the clinical and immunological course or in the long-term remission rate of Graves' hyperthyroidism when the treatment is initiated with either a small single daily dose (15 mg) or the conventional regimen (10 mg 3 times daily).

Minimal residual disease with TEL-AML1 fusion transcript in childhood acute lymphoblastic leukaemia with t(12;21)

We analysed the TEL-AML1 transcript using reverse transcription-polymerase chain reaction (RT-PCR) in order to detect minimal residual disease (MRD) in seven children with t(12;21)-associated B-lineage ALL. Leukaemic cells with the TEL-AML1 transcript appear to be very sensitive to chemotherapy, and may be eradicated in most patients if adequate chemotherapy is given. However, a small number of patients with t(12;21) ALL may relapse under the currently used chemotherapy, and we believe that RT-PCR for detecting MRD with the transcript is a suitable tool for monitoring the efficacy of chemotherapy or impending relapse in these patients. We analysed the TEL-AML1 transcript using reverse transcription-polymerase chain reaction (RT-PCR) in order to detect minimal residual disease (MRD) in seven children with t(12;21)-associated B-lineage ALL. Two sets of primers, TEL exon 5 and AML1 exon 3 or 4, detected two types of transcript in four patients and two other types in two other patients. The two different translocation breakpoints in the AML1 gene with or without splicing out of AML1 exon 3 seemed to result in these four types of transcript in leukaemia samples.

BDNF prevents NO mediated glutamate cytotoxicity in cultured cortical neurons

The effects of brain-derived neurotrophic factor (BDNF) on glutamate-induced cytotoxicity were examined using primary cultures of rat cortical neurons. BDNF induced TrkB tyrosine phosphorylation in rat cultured cortical neurons. The cell viability was significantly reduced when cultures were briefly exposed to glutamate and incubated with normal medium for 24 h. Glutamate cytotoxicity was prevented by MK-801, which is a non-competitive blocker of N-methyl-D-aspartate and N(omega)-nitro-L-arginine, which is a blocker of nitric oxide synthetase. Delayed neurotoxicity was also induced by ionomycin, a calcium ionophore, and nitric oxide (NO) donors such as S-nitrosocysteine (SNOC) and 3-morpholinosydnonimine (SIN-1). Incubating cultures with BDNF for 10 min to 24 h protected cortical neurons against glutamate neurotoxicity. The protective effects of BDNF against glutamate cytotoxicity were dependent on both its concentrations and incubation time. BDNF also prevented the ionomycin-, SNOC-, and SIN-1 induced cytotoxicity. These results indicate that BDNF protects cultured cortical neurons from NMDA receptor-mediated glutamate neurotoxicity by reducing cytotoxic action of NO.

The melanin biosynthesis genes of Alternaria alternata can restore pathogenicity of the melanin-deficient mutants of Magnaporthe grisea

The phytopathogenic fungi Magnaporthe grisea and Alternaria alternata produce melanin via the polyketide biosynthesis, and both fungi form melanized colonies. However, the site of melanin deposition and the role of melanin in pathogenicity differ between these two fungi. M. grisea accumulates melanin in appressoria, and their melanization is essential for host penetration. On the other hand, A. alternata produces colorless appressoria, and melanin is not relevant to host penetration. We examined whether the melanin biosynthesis genes of A. alternata could complement the melanin-deficient mutations of M. grisea. Melanin-deficient, nonpathogenic mutants of M. grisea, albino (Alb-), rosy (Rsy-), and buff (Buf-), were successfully transformed with a cosmid clone pMRB1 that carries melanin biosynthesis genes ALM, BRM1, and BRM2 of A. alternata. This transformation restored the melanin synthesis of the Alb- and Buf- mutants, but not that of the Rsy- mutant. The melanin-restored transformants regained mycelial melanization, appressorium melanization, and pathogenicity to rice. Further, transformation of Alb- and Buf- mutants with subcloned ALM and BRM2 genes, respectively, also produced melanin-restored transformants. These results indicate that the Alternaria genes ALM and BRM2 can restore pathogenicity to the mutants Alb- and Buf-, respectively, due to their function during appressorium development in M. grisea.

Menkes' kinky hair disease associated with a large bladder diverticulum: a case report

We report a 2 year-old boy with Menkes' kinky hair disease associated with a solitary huge bladder diverticulum. To our knowledge this is the first reported case treated successfully by surgical excision under general anesthesia, which has been previously considered hazardous due to the poor general condition of the patient.

[Hemo-lymphangioma of the scrotum: a case report]

A 3-year-old boy was referred because of a painless mass in the left scrotum. On palpation, the mass was discriminated from the testis, epididymis and spermatic cord and showed transillumination. A part of the mass was dark purple in color. Total surgical excision of the mass was performed. The lesion was multicystic (2-15 mm), adherent to the scrotal skin, and easily dissectable from the testicle. Pathological examination revealed lymphangioma as a major component and hemangioma as a minor part. He has been free of recurrent disease for 2 years. This is the 7th case of hemo-lymphangioma of the scrotum in the Japanese literature.

Sequential cis/trans autophosphorylation in TrkB tyrosine kinase

TrkB, a member of the tyrosine kinase family of growth factor receptors, is activated by binding of brain-derived neurotrophic factor or neurotrophin 4/5. The intracellular kinase domain of TrkB (ICD-TrkB) was prepared by an insect cell expression system and characterized to identify the mechanism of autophosphorylation. The time course of autophosphorylation, which shows a biphasic progression with a slow nonlinear phase followed by a fast linear phase, indicates the existence of autophosphorylation-induced activation in ICD-TrkB. This is also supported by the finding that phosphorylated ICD-TrkB shows significantly higher activity than control naive ICD-TrkB. Interestingly, the autophosphorylation rate in the linear phase clearly depends on the ICD-TrkB concentration, whereas the rate of initial autophosphorylation is independent of the concentration of ICD-TrkB in the reaction mixture. This observation suggests a two-step autophosphorylation, first an intramolecular activating step and then an intermolecular step. This mechanism is confirmed by the result that only the later phase of autophos-phorylation is inhibited by addition of glycerol which interferes with intermolecular interactions. Therefore, we propose the mechanism of ICD-TrkB autophosphorylation as a sequential cis/trans phosphorylation.

Induction of a distinct morphology and signal transduction in TrkB/PC12 cells by nerve growth factor and brain-derived neurotrophic factor

A clonal cell line stably expressing trkB (TrkB/ PC12) was established from rat pheochromocytoma PC12 cells. Brain-derived neurotrophic factor (BDNF), as well as nerve growth factor (NGF), stimulates neurite outgrowth in TrkB/PC12 cells. However, the morphology of BDNF-differentiated cells was clearly different from NGF-differentiated cells. BDNF treatment brought about longer and thicker neurites and induced a flattened soma and an increase in somatic size. This is not explained enough by the quantitative difference in the strength between TrkA and TrkB stimulation, because the level of BDNF-stimulated tyrosine phosphorylation of TrkB was similar to that of TrkA stimulated with NGF in PC12/TrkB cells. There was no difference in major tyrosine phosphorylated proteins induced by NGF and BDNF. Signal proteins such as phosphatidylinositol 3-kinase, phospholipase C-gamma 1, Shc, and mitogen-activated protein kinase seem to be involved in both TrkA- and TrkB-mediated signaling pathways. However, a tyrosine-phosphorylated 38-kDa protein (pp38) was detected in anti-pan-Trk immunoprecipitation only after NGF stimulation. Immunoprecipitation using three distinct anti-pan-Trk antibodies suggests that pp38 is not a fragment of TrkA. These data indicate that TrkA has a unique signal transduction pathway that is not stimulated through TrkB in TrkB/PC12 cells and suggest distinct functions among neurotrophin receptors.

[Myelogenous leukemia in children. ANLL9205 study by Children's Cancer and Leukemia Study Group (CCLSG)]

Treatment results were evaluated in 45 children with acute myeloblastic leukemia (AML) treated on the ANLL-9205 protocol of the Children's Cancer Leukemia Study Group (CCLSG, Japan). In this protocol, terarubicin (THP-ADR), vincristine and continuous infusion of cytosine arabinoside (Ara C) were applied for remission induction therapy (AVC), and VP16+ high dose Ara C were used sequentially for 32 or 48 weeks. Eleven patients received stem cell transplantation. Thirty-eight out of the 43 eligible patients (88.4%) achieved complete remission, and the overall 3-year event-free survival (EFS) was 55.6% (S.E.,10%). This favorable response was attributed mainly to the high induction rate of patients with the M5, M7 FAB subtypes and higher WBC counts (> or = 10 x 10(9)/L). There was no difference in the 3-year EFS of these patients who discontinued treatment between 32 weeks and 48 weeks. Serious toxicities were not observed in this study. These findings suggest that the ANLL-9205 protocol is an effective and safe treatment regimen for childhood AML. When comparing the treatment period of 32 or 48 weeks, the difference was not statistically significant.

Tyrosine phosphorylation of ErbB4 is stimulated by aurintricarboxylic acid in human neuroblastoma SH-SY5Y cells

Aurintricarboxylic acid (ATA) has been reported to protect PC12 cells and cultured neuronal cells from serum starvation-induced cell death, and hippocampal neurons from N-methyl D-aspartate- or ischemia-induced cell death in vivo. We have found that ATA activated tyrosine phosphorylation cascade in PC12 cells as growth factors. Here, we report that ATA prevents cell death under serum starvation and induces tyrosine phosphorylation also in human neuroblastoma SH-SY5Y cells. Furthermore, it was found that erbB4, a member of epidermal growth factor receptor family, is tyrosine-phosphorylated in response to ATA. Both, erbB4 and its ligand, neu differentiation factor (NDF)/ heregulin family, have been reported to be expressed abundantly in nervous system. Thus, tyrosine phosphorylation of erbB4 might explain the neuro-protective activity of ATA.

Overview of clinical studies of childhood acute lymphoblastic leukemia for more than ten years by the Japanese Children's Cancer and Leukemia Study Group

Since 1981, the Children's Cancer and Leukemia Study Group (CCLSG) has developed a series of protocols for treatment of acute lymphoblastic leukemia (ALL) in childhood. In the first randomized controlled study of the 811 protocol (1981-1983) a comparison of conventional daily 6-mercaptopurine and methotrexate with a pulsed regimen of the two drugs was performed. The superiority of the pulsed regimen was shown. In the next 841 protocol (1984-1987) a comparison of two drugs and three drugs during induction therapy was conducted. The three-drug regimen resulted in a significantly higher event-free survival (EFS) rate. In the 874 protocol (1987-1990) two regimens with or without cranial irradiation were randomly compared, and there was no significant difference between the two regimens for the standard-risk group. To further improve the EFS rate a risk group-directed protocol 911 was conducted starting in January 1991. Life-table analysis of serial CCLSG protocols revealed that the outcome of overall ALL has gradually improved with an increase of the EFS rate; 41.4% +/- 3.6% at 14 years for the 811 protocol, 51.3% +/- 3.5% at 11 years for the 841 protocol, 56.7% +/- 3.1% at 8 years for the 874 protocol, and 78.2% +/- 3.1% at 4 years for the more recent 911 protocol.

SHP-2 is involved in neurotrophin signaling

To investigate the involvement of SHP-2 in the signal transduction pathway stimulated by neurotrophins, the association of SHP-2 with components of the pathway was examined. Following NGF stimulation of PC12 cells, SHP-2 was found to be associated with the p85 subunit of PI3-kinase and the Shc proteins. In retinoic acid-differentiated SH-SY5Y cells and primary cultures of rat cortical neurons, BDNF treatment similarly caused the association of SHP-2 with p85. In addition, a tyrosine-phosphorylated protein, which is probably TrkB, was coimmunoprecipitated with SHP-2 in both cultures. These results show that SHP-2 becomes associated with signaling proteins after treatment with neurotrophins and suggest that SHP-2 plays a fundamental role in neurotrophin signaling.

Primary aldosteronism with bilateral multiple aldosterone-producing adrenal adenomas

A 41-year-old woman developed primary aldosteronism due to bilateral multiple aldosterone-producing adenomas (APA). She was suspected to have idiopathic hyperaldosteronism (IHA) 7 years previously. Although preoperative data suggest APA and IHA was suspected in a postoperative microscopic specimen, a definite clinical diagnosis could not be made. Cytochrome P-450 and other enzymes involved in aldosterone synthesis were found in the tumor portions but not in the zona glomerulosa of attached adrenals, which histopathologically showed "paradoxical hyperplasia". This was a rare case of bilateral multiple APA, which could be differentiated from IHA by immunohistochemical analysis of adrenal steroidogenic enzymes.

Implication of ATP receptors in brain functions

The possible implication of P2-purinoceptors in brain functions is reviewed. Involvement of P2-purinoceptors in memory and learning (Section 2) is suggested by ATP release from hippocampal slices [Wieraszko, A., Goldsmith, G. and Seyfried, T. N. (1989) Brain Res. 485, 244-250], induction of fast synaptic currents in cultured hippocampal neurons [Inoue, K., Nakazawa, K., Fujimori, W. and Takanaka, A. (1992a) Neurosci. Lett. 134, 294-299] and long-lasting enhancement of the population spikes [Wieraszko, A. and Seyfried, T. N. (1989) Brain Res. 491, 356-359; Nishimura, S., Mohri, M., Okada, Y. and Mori, M. (1990) Brain Res. 525, 165-169; Fujii, S., Kato, H., Furuse, H., Ito, K., Osada, H., Hamaguchi, T. and Kuroda, Y. (1995) Neurosci, Lett. 187, 130-132], as well as ATP release on glutamate stimulation to evoke an increase in intracellular Ca2+ in hippocampal cells [Inoue, K., Koizum, S. and Nakazawa, K. (1995) NeuroReport 6, 437-440]. Moreover, mRNAs for certain types of P2x-purinoceptors are present in the hippocampus [Collo, G., North, R. A., Kawashima, E., Merlo-Pich, E., Neidhart, S., Surprenant, A. and Buell, G. (1996) J. Neurosci. 16, 2495-2507]. It is likely, therefore, that ATP may be involved in modulation of synaptic efficiency in the hippocampus. The implication of ATP in schizophrenia is suggested by the fact that antipsychotic drugs inhibit ATP-evoked responses in PC12 cells [Koizumi, S., Ikeda, M., Nakazawa, K., Inoue, K., Ito, K. and Inoue, K. (1995b) Biochem. Biophys. Res. Commun. 210, 624-630] without blocking the action of dopamine D2 receptors. Involvement of P2-purinoceptors in Sections 4 ("Pain and cognition") and 5 ("Central regulation of the autonomic system") are also discussed.

Nerve growth factor induces resistance of PC12 cells to nitric oxide cytotoxicity

Nitric oxide (NO) donors, sodium nitroprusside and NOC 7, caused pheochromocytoma (PC12) cell death in a concentration and time-dependent manner. This cytotoxicity was blocked by the NO trapping agent, oxyhemoglobin. A membrane permeable cGMP analogue had no cytotoxicity in a reasonable concentration. Moreover, the selective inhibitor of cGMP-dependent protein kinase, KT5823, had no effect on NOC 7 cytotoxicity. These results suggest that NO caused PC12 cell death but not through the cGMP pathway. Additionally, this NO-induced PC12 cell death is not accompanied by DNA fragmentation. Nerve growth factor (NGF), which is able to rescue PC12 cells from serum deprivation, failed to protect PC12 cells from NO-induced cell death by acute treatment. However, PC12 cells differentiated by NGF treatment for more than 3 days did not die after NO exposure. The differentiated PC12 cells, but not undifferentiated cells, expressed NO synthase (NOS). NGF-differentiated PC12 cells acquired the resistance to NO, by a mechanism not yet identified, accompanied by the expression of NOS.

Inhibition by antipsychotic drugs of L-type Ca2+ channel current in PC12 cells

Inhibition by antipsychotic drugs of voltage-gated L-type Ca2+ channels was characterized in rat neuronal cell line pheochromocytoma PC12 cells. Under whole-cell voltage-clamp, haloperidol and chlorpromazine (1-100 microM) inhibited Ba2+ current permeating through Ca2+ channels. Fluspirilene and pimozide the Ba2+ current at lower concentrations (fluspirilene, 0.1 pM to 1 nM; pimozide 10 pM to 1 microM). Effects of dopamine receptor antagonists and calmodulin antagonists were tested because antipsychotic drugs are known to exhibit these pharmacological activities. Sulpiride (1 and 10 microM), an antagonist to dopamine D2 receptors, and SCH-23390 (R(+)-7-chloro-8-hydroxy-3-methyl-l-phenyl-2,3,4,5-tetrahydro-1H-3- benzazepine; 1 and 10 microM), an antagonist to dopamine D1 receptors, also inhibited the Ba2+ current. As for calmodulin antagonists, W-7 (N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide; 10 and 100 microM) as well as calmidazolium (10 nM to 1 microM) reduced the Ba2+ current. The inhibition by haloperidol or fluspirilene of the Ba2+ current was not affected when GTP in intracellular solution was replaced with GDP beta S. These properties of the Ca2+ channel inhibition are discussed by comparing with those of the K+ channel inhibition and in relation to therapeutic relevance.

Detection and quantification of TEL/AML1 fusion transcripts by polymerase chain reaction in childhood acute lymphoblastic leukemia

We investigated TEL/AML1 fusion mRNA in 108 children with acute lymphoblastic leukemia (ALL) (86 B-lineage ALL, 15 T-ALL, two mixed lineage ALL, and five other phenotypes) using reverse transcriptase-polymerase chain reaction (RT-PCR). TEL/AML1 transcripts were found in 14 patients (13%) including three relapsed patients, and were unexceptionally limited to B-lineage ALL patients. The incidence of TEL/AML1 transcripts among B-lineage ALL was 16% (14/86). The reciprocal AML1/TEL transcripts were detected in 12 (86%) of the 14 cases expressing a TEL/AML1 transcript. In three cases, the TEL gene was fused to exon 3 of the AML1 gene, and to exon 2 in the remaining cases. To evaluate the amount of TEL/AML1 molecules for the quantification of a minimal residual disease (MRD), a plasmid vector which contained either a long TEL/AML1 PCR product (464 bp) or a short one (425 bp) was used as a competitor. We amplified RNAs obtained from bone marrow (BM) at complete remission or from peripheral blood stem cell (PBSC) harvests in two representative cases. For one PBSC harvest showing a positive result, a competitive PCR was carried out to quantify the amount of MRD. A 1:4 dilution series of competitor vectors was constructed, and each vector was added to a PCR reaction which contain a constant amount of cDNA obtained from the PBSC harvest. An equivalent point was compared to that of corresponding samples at diagnosis. Using this method, MRD in the PBSC harvest was 3.9:10(3). Our results elucidated the incidence, lineage-specificity, and variant forms of TEL/AML1 fusion transcripts in childhood ALL. Since the percentage of other chromosomal translocations in childhood ALL is not more than 5%, TEL/AML1 transcript would be the most feasible clone-specific marker for these patients. In addition, our method could be a powerful tool for quantification of the TEL/AML1 transcript and for the detection of MRD.

Transcriptional analysis of Epstein-Barr virus gene expression in EBV-positive gastric carcinoma: unique viral latency in the tumour cells

Although case-oriented evidence for an association of Epstein-Barr virus (EBV) with gastric carcinoma has been accumulating recently, the interaction(s) between EBV and gastric epithelial cells is/are largely unknown. In this study, we examined seven EBV-positive gastric carcinoma tissues for viral gene expression at the mRNA level, from which studies on the EBV oncogenicity in human epithelial cells will benefit. Reverse transcription-PCR analysis showed that all seven EBV-positive tumour tissues constitutively expressed EBV nuclear antigen (EBNA) 1 mRNA, but not EBNA2 mRNA. The EBNA transcription was initiated from one of three EBNA promoters, Qp: by contrast, both Cp and Wp were silent, thus resulting in the lack of EBNA2 mRNA. Latent membrane protein (LMP) 2A mRNA was detected in three of seven cases; however, neither LMP1 nor LMP2B mRNA was detected in any of the tumours tested. Transcripts from the BamHI-A region of the viral genome were detectable in all cases. BZLF1 mRNA and the product, an immediate-early gene for EBV replication, was not expressed in any of them, thereby suggesting that the tumour cells carried EBV genomes in a tightly latent form. These findings further extended our previous data regarding EBV latency in gastric carcinoma cells at the protein level, and have affirmed that the programme of viral gene expression in the tumour more closely resembles 'latency I' represented by Burkitt's lymphoma than 'latency II' represented by the majority of nasopharyngeal carcinomas.

Internal stenting of the hepaticojejunostomy and pancreaticojejunostomy in patients undergoing pancreatoduodenectomy to promote earlier discharge from hospital

Internal stenting of the hepaticojejunostomy and pancreaticojejunostomy was performed in 11 consecutive patients undergoing pancreatoduodenectomy between July 1992, and July 1994, to promote earlier discharge from hospital. Although minor leakage of the pancreaticojejunostomy occurred in 4 patients, this resolved within a short period and all 11 patients were able to be discharged by the 29th postoperative day in good health and without any intubation. Follow-up abdominal X-ray and computed tomography (CT) scans proved that all 22 of the stenting tubes had spontaneously fallen out by the 176th postoperative day. No complication related to the stenting tubes occurred in any of our patients.