Effects of caloric vestibular stimulation on prepositus hypoglossi neurons in rats

In our previous study, we found that the majority of locus coeruleus (LC) neurons were inhibited by caloric stimulation and that the inhibition was mediated by gamma aminobutyric acid (GABAA) receptors. It has been reported that the nucleus prepositus hypoglossi (PrH) sends GABAergic inputs to the LC. In the present study, an attempt was made to determine whether PrH neurons contribute to the LC neuronal inhibition caused by caloric stimulation. We characterized the neuronal response in the PrH to caloric stimulation in rats. About three-fourths of PrH neurons showed various responses to both ipsi- and contralateral caloric stimulation, suggesting that PrH neurons receive bilateral vestibular inputs. However, these neurons were not activated by antidromic stimulation of the LC. The remaining one-fourth of the PrH neurons that were antidromically activated did not respond to caloric stimulation. Lesions in the PrH did not attenuate the LC neuronal inhibition caused by caloric stimulation. These findings suggest that the inhibition of LC neurons caused by caloric stimulation is not mediated by the PrH.

Assembly and function of Chlamydomonas flagellar mastigonemes as probed with a monoclonal antibody

Mastigonemes are hair-like projections on the flagella of various kinds of lower eukaryotes. We obtained a monoclonal antibody (mAb-MAST1) to mastigonemes of Chlamydomonas reinhardtii, and found that it reacts with a single flagellar glycoprotein of about 230 kDa. Interestingly, immunofluorescence microscopy demonstrated that mAb-MAST1 recognizes not only the flagellar mastigonemes but also a ring composed of 10 or more particles located in the anterior end of the cell body close to the flagellar bases. The ring structure may be the pool of the mastigoneme protein. When the flagella are amputated, they regenerate to their original length in 90–120 minutes. We found that mastigonemes appear on the new flagellar surface as early as 15 minutes after deflagellation, and that new mastigonemes are mostly assembled onto the distal region of the flagellar surface. Mastigonemes thus appear to be inserted into the membrane only in the distal region of the flagellum. Alternatively, mastigonemes may be inserted at the base and transported very rapidly to the distal portion where they are trapped. When live cells are treated with mAb-MAST1, mastigonemes disappear from the flagellar surface. In these mAb-MAST1 treated cells, the swimming velocity decreases to 70–80% of the normal value, although the flagellar beat frequency increases to approximately 110% of the control. These findings demonstrate vectorial transport of mastigonemes to their assembly sites, and show that mastigonemes function to increase flagellar propulsive force by increasing the effective surface of the flagellum.

Endogenous endotoxemia after massive hepatectomy and portal vein stenosis: beneficial effect of a prostaglandin I2 analogue on intestinal permeability

Portal vein (PV) stenosis may contribute to operative death after extended hepatectomy combined with PV reconstruction leading to impairment of the intestinal mucosal barrier. This study was designed to investigate whether rats undergoing such surgery developed endogenous endotoxemia and increased intestinal permeability. The effect of a prostaglandin I2 (PGI2) analogue on mucosal barrier function was also studied. The rats were divided into the following five groups: sham operation, massive hepatectomy (Ht), PV stenosis (PS), combined Ht and PS (Ht+PS), and Ht+PS with subcutaneous injection of PGI2 preoperatively (PG). The 10-day survival rate, portal endotoxin level and intestinal permeability (two-sugar test) were evaluated in each group. The Ht+PS group showed a significant increase in both the portal endotoxin level and intestinal permeability (p < 0.05) and a significant worse 10-day survival (p < 0.01) than the other four groups. PGI2 pretreatment did not influence splanchnic blood flow, but decreased the endotoxin level and reduced intestinal permeability. In conclusion, the synergistic effect of massive hepatectomy and PV stenosis induced an increased intestinal permeability and consequently endotoxemia. PGI2 pretreatment significantly improved both intestinal barrier function and survival.

Hepatopancreatoduodenectomy for superficially spreading bile duct carcinoma: a report of two 5 year survivals

We have treated two bile duct carcinoma patients using HPD and they have both survived for more than 5 years postoperatively. In this article, we report on the details of these two cases and discuss the indications for HPD in the treatment of bile duct carcinoma.

Plasma serotonin and platelet aggregation during ischemia-reperfusion in dogs: effect of dipyridamole and coenzyme Q10

Platelet aggregation and plasma serotonin were studied during ischemia-reperfusion of the small intestine in dogs. Blood was withdrawn from the superior mesenteric vein before and 1 h after ischemia, then 5, 30 and 60 min after reperfusion. Dipyridamole (5 mg/kg body weight) and coenzyme Q10 (CoQ10; 10 mg/kg body weight) were administered intravenously 5 min before reperfusion, following 1 h ischemia, in order to investigate their effects on platelet function and free serotonin. Ischemia-reperfusion resulted in an increased local free serotonin concentration together with an enhanced platelet response to ADP, collagen and arachidonic acid. Administration of dipyridamole and CoQ10 prior to reperfusion prevented, at least in part, augmented platelet activation and serotonin release. It appeared that dipyridamole was more potent than CoQ10. Our results may indicate a possible protective effect of dipyridamole on enhanced platelet activation during ischemia-reperfusion in dogs.

Clinical and immunogenetic investigation of a Laotian patient with Vogt-Koyanagi-Harada's disease

Vogt-Koyanagi-Harada's (VKH) disease has been known to be associated with HLA class II antigen, HLA-DR4 and -DR53. Recent recombinant DNA technical advances have allowed us to investigate the genetic polymorphism of HLA antigens at the molecular level. By use of the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) technique we have found that VKH disease is closely associated with HLA-DRB1*04 (DRB1*0405/ DRB1*0410) and DQB1*04 (DQB1*0401/DQB1*0402) in the Japanese. Here, we will describe a typical case of a Laotian patient with VKH disease and the results of HLA typing: the patient showed a conservation of one of the major haplotypes observed in Japanese VKH patients, DRB1*0405-DQB1*0402.

Inhibitory effect of MK-801 on amantadine-induced dopamine release in the rat striatum

In the present study, we examined the effect of amantadine on extracellular dopamine levels in the rat striatum using an in vivo microdialysis. Perfusion of amantadine (0.1-1 mM) through the microdialysis probe caused an increase both in extracellular dopamine and glutamate levels in rat striatum. Amantadine was found to increase extracellular dopamine concentration in Ca(2+)-dependent manner, but the effect was not abolished by omega-conotoxin. Although intraperitoneal administration of MK-801 [(+)-5-methyl-10, 11-dihydroxy-5H-dibenzo (a,d)cyclohepten-5,10-imine] alone could not significantly alter the concentration of dopamine, it attenuated amantadine-induced increase in dopamine level. These findings suggest that an interaction between dopaminergic and glutamatergic neurotransmission is an important component in the regulation of striatal dopamine levels.

Acute myelomonocytic leukaemia with 11q23 abnormality during multiple myeloma: is this related to anthracycline?

The clinical course of a 66-year-old man diagnosed with multiple myeloma is described. Chemotherapy including alkylating agents had no effect, and so he was treated with vincristine, doxorubicin, and dexamethasone. His bone tumor was treated with localized radiation after two courses of chemotherapy. After these treatments, monocytosis was found and dysplastic changes were noted in the bone marrow. A cytogenetic study revealed t(9;11)(p22;q23), an abnormality which had previously been absent. A diagnosis of myelodysplastic syndrome (MDS) was newly established, and transformation to acute non-lymphocytic leukaemia (ANLL) was observed 6 months later. The cumulative doses of melphalan, cyclophosphamide, doxorubicin, and radiation therapy were 432 mg, 4,200 mg, 120 mg, and 4,000 cGy, respectively. The cytogenetic abnormality suggested that this patient's MDS/ANLL was related to doxorubicin and not talk to alkylating agents, although the dose of doxorubicin administered was quite low.

Effects of cyclic adenosine 3',5'-monophosphate on chondrocyte terminal differentiation and cartilage-matrix calcification

We examined the effects of cyclic AMP on terminal differentiation and calcification in rabbit growth plate chondrocyte cultures. Dibutyryl cAMP (dbcAMP), as well as 8-bromo-cAMP abolished the increases in chondrocyte size, alkaline phosphatase activity, type X collagen synthesis, 1 alpha, 25-dihydroxyvitamin D3 receptor synthesis, the incorporation of 45Ca into insoluble material, and the calcium content. All of these occurred in parallel untreated cultures during the hypertrophic (terminal) stage. The inhibition of alkaline phosphatase by dbcAMP was detectable after 24 h, and this effect was reversible. dbcAMP and 8-bromo-cyclic AMP inhibited alkaline phosphatase induction and calcification at low concentrations (3-5 microM), whereas 10-30-fold higher concentrations were required to stimulate proteoglycan synthesis. These findings suggest that cAMP plays a crucial role in suppressing terminal differentiation of chondrocyte and cartilage-matrix calcification.

Medullary thyroid carcinoma experienced at Kanazawa University Hospital

Eleven cases of medullary thyroid carcinoma (MTC), which were experienced at Kanazawa University Hospital between 1975 and 1993, were examined to correlate the clinical, histologic, and immunohistochemical findings. Seven patients were women and four men, and the mean age was 46.6 years. The mean follow-up was 88.3 months. Three patients had familial non-multiple endocrine neoplasia (MEN) MTC (familial MTC unassociated with other endocrinopathies) and the remaining eight had sporadic disease. At the end of the observation period, six patients were alive without disease and four were alive with metastatic disease. One patient died of MTC 8.3 years after surgery. Thus, the 10-year survival and disease-free survival rates were 67% and 53%, respectively. Histologically MTCs from the 10 surviving patients showed a classic type, while the one patient who died had a tubular variant MTC. Immunohistochemically, there were no significant correlations between the outcome of the patients and the expression of calcitonin (CT), carcinoembryonic antigen (CEA), calcitonin gene-related peptide (CGRP), or chromogranin A (CgA) in the primary tumors, and there were no differences in expression of these antigens between the primary and the recurrent tumors. Although only a small number of patients with MTC were studied here, it was suggested that the prognosis of MTC is worse than that of papillary and follicular thyroid carcinoma. The patients with lymph node involvement at the time of primary surgery showed a high risk of persistent or recurrent disease. The expressional level for the antigens did not influence the prognosis of MTC.

The role of proteolytic enzymes in the deposition of amyloid proteins

Serum albumin from normal individuals and short-term hemodialysis patients was separated by isoelectric focusing into two bands with pIs of 4.7 (Alb-I) and 4.2 (Alb-II). However, serum albumin from long-term hemodialysis patients with CTS migrated as a single band with a pI of 4.2 (Alb-II). The major constituent of the 100,000 x g supernatant proteins from amyloid tissues that were collected from hemodialysis patients with CTS was Alb-II. Incubation of serum albumin by lysosomal enzymes in vitro caused the modification of Alb-I to Alb-II. The ratio of Alb-I/Alb-II was changed in vivo during the hemodialysis and in in-vitro experiments designed to circulate the sera. Lysosomal enzyme levels such as acid phosphatase, glucosidase, glucuronidase and dipeptidyl aminopeptidase in the serum of hemodialysis patients were higher than those of normal individuals. Plasma levels of acid phosphatase and cathepsin L were elevated during hemodialysis. These results suggest that the conformational change of serum albumin by proteolytic modification during hemodialysis may be involved in the hemodialysis-associated amyloidosis.

Liposomal ATP protects the liver from injury during shock

Liposomes are useful drug carriers. In this study, adenosine triphosphate (ATP) was entrapped in liposomes (Lip-ATP). Anesthetized rats were given Lip-ATP (5 mg/kg as ATP), free ATP (5 mg/kg) or saline (control group) during stabilization. Then, the rats were exposed to 30 min of hypovolemic shock and 30 min of reperfusion. Administration of Lip-ATP significantly improved hepatic blood flow during shock (13.2 +/- 1.7 ml/min/100 g tissue in the Lip-ATP group vs. 9.4 +/- 2.2, in the control group, and 8.9 +/- 2.9 in the free ATP group) and during reperfusion (20.9 +/- 2.3, 16.3 +/- 2.2, and 16.2 +/- 1.8 ml/min/100 g tissue, respectively). The serum levels of hepatic enzymes (ALT, AST and LDH) were significantly lower in the Lip-ATP group after reperfusion when compared with the control and free ATP groups. Administration of Lip-ATP also produced the best recovery of hepatic ATP level. These findings indicate that Lip-ATP increased hepatic blood flow during shock and reperfusion, presumably by improving the energy charge and metabolism of the hepatocytes. Thus, Lip-ATP appears to be a useful agent for liver injury induced by hypovolemic shock.

The SH2 domain of Shc suppresses EGF-induced mitogenesis in a dominant negative manner

Recently, we have shown that an EGF-R-mutant lacking the autophosphorylation sites phosphorylates Shc and retains mitogenic activity. In this report, we have shown that in these cells, in response to EGF, Ras is fully activated with formation of the tyrosine-phosphorylated Shc-Grb2-mSOS complex without the receptor. This pointed out the importance of Shc in EGF-induced Ras activation. To investigate the mechanism of tyrosine phosphorylation of Shc by EGF-R, we carried out in vitro kinase assays using immunoprecipitated EGF-R and bacterially-expressed Shc proteins as substrates. The EGF-R phosphorylated Shc, but not the Shc SH2 mutant, lacking binding ability for phosphotyrosine. This suggests that intact Shc SH2 is essential for the full-length Shc to become phosphorylated, probably by inducing a conformational change in Shc. Thus a Shc SH2 peptide may inhibit competitively Shc phosphorylation. We microinjected the Shc SH2 domain into NIH3T3 cells overexpressing the EGF-R. Microinjected Shc SH2 greatly suppressed EGF-induced DNA synthesis. But microinjection of neither the Shc SH2 mutant nor PLC-gamma 1 SH2 had any effect. This suppressing effect was rescued by comicroinjection of the full-length Shc, suggesting Shc SH2 specifically suppressed the Shc pathway. Thus we concluded Shc phosphorylation is crucial, whereas receptor autophosphorylation is dispensable, in EGF-induced mitogenesis.

Mammalian phospholipase D: activation by ammonium sulfate and nucleotides

Phospholipase D (PLD) associated with the rat kidney membrane was activated by guanine 5'-[gamma-thio]triphosphate and a cytosol fraction that contained ADP-ribosylation factor. When assayed by measuring the phosphatidyl transfer reaction to ethanol with exogenously added radioactive phosphatidylcholine as substrate, the PLD required a high concentration (1.6 M) of ammonium sulfate to exhibit high enzymatic activity. Other salts examined were far less effective or practically inactive, and this dramatic action of ammonium sulfate is not simply due to such high ionic strength. Addition of ATP but not of nonhydrolyzable ATP analogue adenosine 5'-[beta, gamma-imido]diphosphate further enhanced the PLD activation approximately equal to 2- to 3-fold. This enhancement by ATP needed cytosol, implying a role of protein phosphorylation. A survey of PLD activity in rat tissues revealed that, unlike in previous observations reported thus far, PLD was most abundant in membrane fractions of kidney, spleen, and liver in this order, and the enzymatic activity in brain and lung was low.

Carboxyl end-specific monoclonal antibodies to amyloid beta protein (A beta) subtypes (A beta 40 and A beta 42(43)) differentiate A beta in senile plaques and amyloid angiopathy in brains of aged cynomolgus monkeys

Senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in the brains of five aged (20-26 years old) cynomolgus monkeys were investigated immunohistochemically using two monoclonal antibodies (anti-A beta 40 (BA27) and anti-A beta 42(43) (BC05)) that can differentiate the carboxyl termini of amyloid beta protein (A beta) subtypes. In four of five animals, all types of SPs (i.e. diffuse, primitive, and classical plaques; DPs, PPs, and CPs, respectively) were identified by BC05. However, BA27 did not label DPs and stained only about one third of PPs and CPs, mainly labeling granular structures and cored portions, respectively. In CAA, lesions of cortical capillaries reacted to BC05 in four of five cases, but rarely and weakly to BA27 in two of five cases. On the other hand, lesions of parenchymal and meningeal arterioles were stained by both BA27 and BC05. These staining profiles of SPs in cynomolgus monkeys correspond well to those in humans, although there are two remarkable features in cynomolgus monkeys. First, BA27 stained PPs associated with granular structures. Secondly, capillary A beta reacted intensely to BC05 but only slightly to BA27. Despite these unique features, the results suggest that aged cynomolgus monkeys can be used to investigate the pathogenesis of A beta deposition in SPs and CAA.

Identification of Rap1 as a target for the Crk SH3 domain-binding guanine nucleotide-releasing factor C3G

C3G, which was identified as a Crk SH3 domain-binding guanine nucleotide-releasing factor, shows sequence similarity to CDC25 and Sos family proteins (S. Tanaka, T. Morishita, Y. Hashimoto, S. Hattori, S. Nakamura, M. Shibuya, K. Matuoka, T. Takenawa, T. Kurata, K. Nagashima, and M. Matsuda, Proc. Natl. Acad. Sci. USA 91:3443-3447, 1994). The substrate specificity of C3G was examined by in vitro and in vivo experiments. C3G markedly stimulated dissociation of bound GDP from Rap1B but marginally affected the same reaction of other Ras family proteins (Ha-Ras, N-Ras, and RalA). C3G also stimulated binding of GTP-gamma S [guanosine 5'-3-O-(thio)triphosphate] to Rap1B. When C3G and Rap1A were expressed in COS7 cells, marked accumulation of the active GTP-bound form of Rap1A was observed, while Sos was not effective in the activation of Rap1A. These results clearly show that C3G is an activator for Rap1. Furthermore, expression of C3G with a membrane localization signal in a v-Ki-ras transformant, DT, induced a reversion of the cells to the flat form, possibly through the activation of endogenous Rap1.

Phylogenetic analysis of phospholipase C genes from Clostridium perfringens types A to E and Clostridium novyi

The phylogenetic interrelationships between strains of 5 toxin types (A to E) of Clostridium perfringens were examined by analysis of differences in the nucleotide sequences of phospholipase C genes (plc genes) among 10 strains, including 3 strains for which the plc gene sequences have been previously reported. A plc gene was also cloned from a Clostridium novyi type A strain and sequenced to analyze the interspecies diversity of plc genes. Phylogenetic trees constructed by the neighbor-joining method revealed that the phylogeny of C. perfringens strains is not related to toxin typing, in agreement with the results of a comparative genome mapping study by Canard et al. (B. Canard, B. Saint-Joanis, and S. T. Cole, Mol. Microbiol. 6:1421-1429, 1992). Various C. perfringens phospholipase C enzymes were purified from cultures of Escherichia coli cells into which the encoding plc genes had been cloned. All of the enzymes showed the same specific activity. On the other hand, the level of plc transcripts differed greatly (up to 40-fold) from one C. perfringens strain to another. No significant difference in the nucleotide sequence of the plc promoter region was observed for any of the plc genes. These results suggest that the variation in phospholipase C activity among different strains is not due to mutation in the plc coding region but to that in an extragenic region. The evolution of C. perfringens phospholipase C is discussed on the basis of similarities and differences between clostridial plc genes.

Angioimmunoblastic T-cell lymphoma (angioimmunoblastic lymphadenopathy with dysproteinemia [AILD]-type T-cell lymphoma) followed by Hodgkin's disease associated with Epstein-Barr virus

A patient is described with angioimmunoblastic T-cell lymphoma (AIL) (angioimmunoblastic lymphadenopathy with dysproteinemia [AILD]-type T-cell lymphoma), which was later followed by Hodgkin's disease. At the time of the initial diagnosis, histological examination of a cervical lymph node showed a typical picture of AIL with abundant clear cells which were CD45RO+, CD43+, and CD20-, and there was no evidence of a monoclonal B-cell proliferation by immunohistochemical analysis. In situ hybridization for Epstein-Barr virus (EBV) was negative. Interposed by a bout of recurrence, the patient developed, 16 years later, a left subparotid mass which showed histologic features of Hodgkin's disease, mixed cellularity type. Diagnostic Reed-Sternberg cells and their variants were CD30+, CD15- and CD20+. Neither rearrangement of TCR beta and gamma chain genes nor of immunoglobulin heavy chain and kappa light chain genes was detected in DNA extract from fresh material. In situ hybridization showed the presence of EBV within the Reed-Sternberg cells. The data show that EBV was not etiologically related to AIL in this case. Further, the deficit in cellular immunity that accompanied AIL conceivably permit primary EBV infection or reactivation of latent infection, which eventuated in development of Hodgkin's disease, but the exact pathogenesis remains uncertain.

[Evaluation of reliability of IPSS by 24-hour uroflowmetry]

BACKGROUND

Although the international prostate symptom score (IPSS) is now often used to assess the symptoms of BPH, whether or not patients answer the questions correctly has not been validated objectively.

METHODS

Reliability of IPSS was evaluated by 24-hour uroflowmetry in 20 hospitalized male patients. Six of them had prostatic hypertrophy or cancer, and the evaluation was performed before and after TURP or hormonal therapy in these six patients. The objective scores for frequency and nocturia were obtained from the time recorded on IC card. The objective score for intermittency was calculated from the uroflow curves.

RESULTS

The answer about frequency was not correct compared with the objective scores for frequency. The answers about nocturia and intermittency were almost the same as the corresponding objective scores. The answer for weak stream correlated with the average of peak flow rate. However, the threshold of peak flow rate for "weak stream" fluctuated markedly before and after the treatment in the same individuals. The answer for hesitancy had no correlation with the hesitation time. Patients seemed to understand the question translated in Japanese as "have you need force to urinate?"

CONCLUSION

Before wider use of IPSS in Japan, the correct translation of the questions and verification of the usefulness of the questions in large number of Japanese patients seem necessary.

Ki-1 (CD30) positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax: report of a case with detection of Epstein-Barr virus genome in the tumor cells

We report a case of CD30 positive anaplastic large cell lymphoma of T-cell phenotype developing in association with long-standing tuberculous pyothorax. Phenotypic analysis showed CD1a-, CD2+, CD3+, CD4+, CD5-, CD8-, CD10-, CD19-, CD20 +/-, CD21-, CD25-, CD56-, T-cell receptor (TCR) alpha/beta antigens-, and HLA-DR+ phenotype. Neither rearrangement of TCR beta and gamma chain genes or of immunoglobulin heavy chain gene was detected in DNA extract from fresh material. The lymphoma cells were also shown to express the latent membrane protein-1 and the Epstein-Barr virus (EBV)-encoded nuclear antigen-2 by immunohistochemistry and EBV-encoded small RNAs by in situ hybridization.