Signal transducer and activator of transcription (Stat) 5 controls the proliferation and differentiation of mammary alveolar epithelium

Functional development of mammary epithelium during pregnancy depends on prolactin signaling. However, the underlying molecular and cellular events are not fully understood. We examined the specific contributions of the prolactin receptor (PrlR) and the signal transducers and activators of transcription 5a and 5b (referred to as Stat5) in the formation and differentiation of mammary alveolar epithelium. PrlR- and Stat5-null mammary epithelia were transplanted into wild-type hosts, and pregnancy-mediated development was investigated at a histological and molecular level. Stat5-null mammary epithelium developed ducts but failed to form alveoli, and no milk protein gene expression was observed. In contrast, PrlR-null epithelium formed alveoli-like structures with small open lumina. Electron microscopy revealed undifferentiated features of organelles and a perturbation of cell-cell contacts in PrlR- and Stat5-null epithelia. Expression of NKCC1, an Na-K-Cl cotransporter characteristic for ductal epithelia, and ZO-1, a protein associated with tight junction, were maintained in the alveoli-like structures of PrlR- and Stat5-null epithelia. In contrast, the Na-Pi cotransporter Npt2b, and the gap junction component connexin 32, usually expressed in secretory epithelia, were undetectable in PrlR- and Stat5-null mice. These data demonstrate that signaling via the PrlR and Stat5 is critical for the proliferation and differentiation of mammary alveoli during pregnancy.

Esophagogastrostomy reconstruction after limited proximal gastrectomy

BACKGROUND/AIMS

Recent advances in diagnostic techniques have led to the detection of an increasing number of early gastric cancers in the upper third of the stomach. The objective of this study was to determine the most appropriate surgical treatment for these cancers.

METHODOLOGY

The clinicopathologic characteristics of 35 patients with early gastric cancer in the upper third of the stomach who underwent three different types of gastrectomies were reviewed retrospectively from hospital records between January 1992 and August 1999.

RESULTS

Patients undergoing limited proximal gastrectomy with esophagogastrostomy reconstruction had shorter operation times and less blood loss than those for patients undergoing total gastrectomy or proximal gastrectomy with jejunal interposition. No lymph node metastasis was identified in any of these patients. Heartburn due to reflux esophagitis was seen in a few patients of each group, but they were successfully treated by antacids. The extreme reduction in food intake volume was more frequently experienced in patients with total gastrectomy than those with both proximal gastrectomies. When mortality due to other disease was excluded, all patients survived without recurrence.

CONCLUSIONS

A limited proximal gastrectomy with esophagogastrostomy reconstruction decreased surgical risk and realized preservation of maximal function.

a4, a unique kidney-specific isoform of mouse vacuolar H+-ATPase subunit a

The vacuolar-type H+ -ATPase (V-ATPase) translocates protons across membranes. Here, we have identified a mouse cDNA coding for a fourth isoform (a4) of the membrane sector subunit a of V-ATPase. This isoform was specifically expressed in kidney, but not in the heart, brain, spleen, lung, liver, muscle, or testis. Immunoprecipitation experiments, together with sequence similarities for other isoforms (a1, a2, and a3), indicate that the a4 isoform is a component of V-ATPase. Moreover, histochemical studies show that a4 is localized in the apical and basolateral plasma membranes of cortical alpha- and beta-intercalated cells, respectively. These results suggest that the V-ATPase, with the a4 isoform, is important for renal acid/base homeostasis.

Prostanoids in the preoptic hypothalamus mediate systemic lipopolysaccharide-induced hyperalgesia in rats

The systemic administration of lipopolysaccharide (LPS), an experimental model of systemic bacterial infection is known to modulate nociception. It increases the prostaglandin E(2) (PGE(2)) levels in the preoptic area of the hypothalamus (POA) and the microinjection of PGE(2) into the POA and the neighboring basal forebrain induces hyperalgesia. We, therefore, hypothesized that the PGE(2) synthesized in these regions mediates intravenous (i.v.) LPS-induced hyperalgesia. To test this hypothesis, we microinjected cyclooxygenase (COX) inhibitors into several sites in the rat hypothalamus and observed their effects on the LPS (0.1-100 microg/kg, i.v.)-induced changes in nociceptive behavior as assessed by a plantar test. LPS (10 and 100 microg/kg, i.v.) reduced the paw-withdrawal latency at 90 min and 45-60 min after injection, respectively, both thus indicating a hyperalgesic effect. This hyperalgesia was observed only in the period before the development of fever which started 120-135 min after the LPS injection. The LPS (100 microg/kg, i.v.)-induced hyperalgesia was completely abolished by pretreatment with the microinjection of diclofenac (an inhibitor of COX-1 and 2) at 1.0 ng into the bilateral POA. Furthermore, it was also blocked by the microinjection of NS-398 (a selective COX-2 inhibitor) at 1.0 ng into the bilateral POA and the horizontal limb of the diagonal band of Broca (DBB), but not the lateral hypothalamic area, the paraventricular hypothalamic nucleus, and the ventromedial hypothalamic nucleus. These findings suggest that LPS (i.v.)-induced hyperalgesia is mediated predominantly through a COX-2 induced prostanoids in the POA and the DBB in rats.

A lack of consistent amino acid substitutions in NSP4 between rotaviruses derived from diarrheal and asymptomatically-infected kittens

Nonstructural glycoprotein NSP4 of group A rotavirus has recently been shown to be a viral enterotoxin, inducing diarrhea in neonatal mice. Literature is conflicting as to whether there is any consistent amino acid substitution between virulent (or symptomatic) and attenuated (or asymptomatic) rotavirus strains. We have sequenced and compared the NSP4 sequences derived from a total of 10 geographically- and serologically-related feline rotavirus strains from both diarrheal and asymptomatically-infected kittens. These NSP4 sequences were closely related to each other and there were differences at 19 amino acid residues, but none was segregated according to whether the strain was isolated from a diarrheal kitten or not. Thus, this study failed to lend support to the contention that mutations in NSP4 play a significant role in the pathogenesis of rotavirus diarrhea. Involvement of other genes may explain the outcome of infection in cats from which these 10 feline rotaviruses were isolated.

New mu-opioid receptor agonists with piperazine moiety

New mu-opioid receptor (MOR) agonists containing piperazine and homopiperazine moieties in the structures were synthesized and their affinities to and agonist potencies on MOR were evaluated. Among the synthesized compounds, 4-[4-(2-methoxyphenyl)piperazin-1-yl]-N,N-dimethyl-2,2-diphenylbutanamide (20 Aa) showed the highest affinity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 cells, and the highest agonist potency on the MOR in isolated guinea-pig ileum preparation.

A novel myocyte-specific gene Midori promotes the differentiation of P19CL6 cells into cardiomyocytes

Although several cardiac-specific transcription factors have been shown to play vital roles in various steps during the heart formation, the precise mechanism of the early stage of cardiogenesis has yet to be elucidated. By differential display technique, we tried to identify molecules that are expressed earlier than cardiac transcription factors such as CSX/NKX2-5 and GATA-4 and are involved in cardiomyocyte differentiation using the P19CL6 cell line, which efficiently differentiates into cardiomyocytes when treated with dimethyl sulfoxide. We isolated a novel gene designated Midori. Its deduced amino acid sequence contained an ATP/GTP-binding site, Ig-like domain, and Kringle-like domain. Northern blot analysis revealed that expression of Midori was restricted to the fetal and adult heart and adult skeletal muscle in mice. In whole mount in situ hybridization, Midori was expressed in cardiac crescent and developing heart but not in somites. The MIDORI protein was localized in the nucleus and overexpression of Midori induced expression of endogenous Midori itself, suggesting that MIDORI may act as a transcriptional regulator. Permanent P19CL6 cell lines overexpressing Midori more efficiently differentiated into cardiomyocytes than did parental cells, whereas those overexpressing the antisense Midori less efficiently differentiated. These results suggest that Midori may promote the differentiation of P19CL6 into cardiomyocytes.

Bamboo node: primary vocal fold lesion as evidence of autoimmune disease

Descriptions of vocal fold lesions related to autoimmune diseases are rare in the literature, and focus mainly on rheumatoid nodules. This is the first report in which autoimmune diseases were promptly suspected by the observation of a unique white transverse submucosal lesion in the vocal fold during clinical examination. This lesion, reported only in autoimmune disease, has been called the bamboo node and its features are different from those of rheumatoid nodules. We report here on two patients who did not have a diagnosis of systemic disease before investigation of their main complaint of hoarseness. At the patients' first visit, vocal fold bamboo nodes were seen in the vocal fold and the otolaryngologist suspected the presence of an autoimmune disease. We requested clinical investigation to clarify our suspicion that there was an underlying systemic disease. After the investigation, both patients were shown to have autoimmune disease, Sjögren's syndrome and systemic lupus erythematous, respectively. This paper emphasizes the important role of the otolaryngologist in the detection of these unique lesions in the vocal folds through the conventional laryngeal methods. These methods consisted of direct observation with a rigid laryngeal endoscope and investigation of the patient's distinctive vibratory pattern by means of laryngeal stroboscopy. The method of treatment we used to obtain the best outcome in terms of voice improvement is also discussed.

Relation of QT-interval variability to ventricular arrhythmias during percutaneous transluminal coronary angioplasty

The present study investigated the role of the dispersion of QT interval in percutaneous transluminal coronary angioplasty (PTCA)-induced ventricular tachyarrhythmias. Patients with effort angina without a previous myocardial infarction (n = 22), who had single-vessel disease of the anterior descending coronary artery (LAD), underwent PTCA if the coronary lesion was 75% or more stenosed in segment 6 or 7 of the LAD. The standard 12-lead ECG was continuously recorded during the procedure. Averaged QTc and QTac intervals, where QTac was the interval from the beginning of QRS complex to the nadir of T wave corrected by Bazett's formula, did not change significantly during PTCA. Of the 22 patients, 7 showed ventricular arrhythmias during PTCA. The maximum difference (deltaQTc) and the standard deviation (QTcSD) of the corrected QT interval in the standard 12-lead ECG increased significantly during PTCA in the 7 patients with ventricular arrhythmias, whereas they decrreased in the 15 patients without ventricular arrhythmias. deltaQTac and QTacSD were not affected by PTCA regardless of ventricular arrhythmias, which shows that the increases in the variation of the ventricular repolarization process play a role in PTCA-induced ventricular arrhythmias.

Effects of antimuscarinic drugs on both urinary frequency and cognitive impairment in conscious, nonrestrained rats

Recent studies indicate a risk of learning and memory impairments when patients with senile dementia are treated with antimuscarinic drugs. In this study, we compared the effectiveness of propiverine hydrochloride (propiverine) and oxybutynin chloride (oxybutynin) on the increased urinary frequency and cognitive impairment induced by nucleus basalis magnocellularis (nBM) lesioning in conscious and nonrestrained rats. For examination of bladder function, nBM-lesioned rats were given total parenteral nutrition regimens for 8 days. Propiverine administered orally at 0.3, 3 and 30 mg/kg on the postoperative day 7 significantly lessened the increase in the frequency of voiding caused by the nBM lesion, whereas oxybutynin administration did not show any improvement at 0.1 or 1 mg/kg but did so at 10 mg/kg. To examine the memory impairment, we trained nBM-lesioned rats in an 8-arm radial maze task for 20 days and then evaluated the effectiveness of oral drug administration on 19th and 20th radial maze performance. The higher rate of errors caused by nBM lesioning was significantly aggravated by oxybutynin at 30 and 100 mg/kg. Propiverine showed slight aggravation of errors, but with no statistical significance at any dose, 30, 100 or 300 mg/kg. These results suggest that propiverine has comparatively less effect on the cognitive impairment than oxybutynin.

Four subunit a isoforms of Caenorhabditis elegans vacuolar H+-ATPase. Cell-specific expression during development

We have identified four genes (vha-5, vha-6, vha-7, and unc-32) coding for vacuolar-type proton-translocating ATPase (V-ATPase) subunit a in Caenorhabditis elegans, the first example of four distinct isoforms in eukaryotes. Their products had nine putative transmembrane regions, exhibited 43-60% identity and 62-84% similarity with the bovine subunit a1 isoform, and retained 11 amino acid residues essential for yeast V-ATPase activity (Leng, X. H., Manolson, M. F., and Forgac, M. (1998) J. Biol. Chem. 273, 6717-6723). The similarities, together with the results of immunoprecipitation, suggest that these isoforms are components of V-ATPase. Transgenic and immunofluorescence analyses revealed that these genes were strongly expressed in distinct cells; vha-5 was strongly expressed in an H-shaped excretory cell, vha-6 was strongly expressed in intestine, vha-7 was strongly expressed in hypodermis, and unc-32 was strongly expressed in nerve cells. Furthermore, the vha-7 and unc-32 genes were also expressed in the uteri of hermaphrodites. RNA interference analysis showed that the double-stranded RNA for unc-32 caused embryonic lethality similar to that seen with other subunit genes (vha-1, vha-4, and vha-11) (Oka, T., and Futai, M. (2000) J. Biol. Chem. 275, 29556-29561). The progenies of worms injected with the vha-5 or vha-6 double-stranded RNA became died at a specific larval stage, whereas the vha-7 double-stranded RNA showed no effect on development. These results suggest that V-ATPases with these isoforms generate acidic compartments essential for worm development in a cell-specific manner.

The importance of peripheral blood leukocytes and macrophage infiltration on bronchial wall wound healing in rats treated preoperatively with anticancer agents

Preoperative chemotherapy is commonly used for small cell lung cancer or advanced non-small cell lung cancer. This study was conducted to investigate the effects of preoperative antineoplastic agents on the postoperative would healing of bronchial anastomoses in a rat model. Cisplatin (CDDP), doxorubicin (ADM), or cyclophosphamide (CPA) was administered either 3 days preoperatively (experiment 1) or 7 days preoperatively (experiment 2). Wound healing was assessed on postoperative days (POD) 3, 5, and 7 after anastomosis of the bronchus, by examining the bursting strength and hydroxyproline tissue content. In experiment 1, significant impairment of wound healing was seen on POD 3 in the CPA-treated rats, but no significant changes were seen in the other groups. Severe leukopenia and marked reduction of macrophage infiltration into the wound were also observed in the CPA-treated rats. The impairment of wound healing coincided with the time of leukopenia and reduced macrophage infiltration into the wounds. In experiment 2, induction chemotherapy did not impair wound healing. Our experimental results suggest that preoperative chemotherapy producing mild leukopenia, or when followed by a sufficient interval to allow for the recovery of myelosuppression, did not impair wound healing of the bronchial anastomoses. The findings of this study also showed that the depletion of macrophages at the anastomotic site is one of the most important causes of impaired wound healing.

Dendritic aberrations in the hippocampal granular layer and the amygdalohippocampal area following kindled-seizures

Amygdaloid kindling is a model of human temporal lobe epilepsy, in which excitability in limbic structures is permanently enhanced by repeated stimulations. We report here dendritic aberrations occurring in mice following kindled-seizures. Adult mice received a biphasic square wave pulse [495+/-25.5 (S.E.M.) microA 60 Hz, 200 micros duration, for 2 s] unilaterally in the basolateral amygdaloid complex once a day and mice with electrophysiologically and behaviorally verified seizures were used in the experiments. The hippocampus and amygdaloid complex contralateral to the lesions were observed by immunofluorescence histochemistry with a somatodendritic marker, microtubule-associated protein 2 (MAP2), showing that kindled-seizures caused hypertrophy of proximal dendrites in the granule cells of the dentate gyrus and in neurons of the amygdalohippocampal area. To further characterize the morphological changes of the dendrites, electron micrographic analysis was performed on the contralateral side. (1) In the granular layer of the dentate gyrus and the amygdalohippocampal area, kindled-seizures generated an increase in the number of dendrites containing polymerized microtubules and width of dendritic profiles showing the increase was in the range 0.2-3.0 and 0.2-1.4 microm, respectively. (2) In the granular layer, bundles between dendrites separated by the puncta adhaerentia increased. (3) In the granular layer, the seizure-induced dendritic aberration was more severe in the rostral than the caudal region. These results suggested that growth of dendrites with enriched-stable microtubules is part of the structural plasticity in response to seizure activity in specific areas of the adult brain.

Loss of expression of alpha4beta7 integrin and L-selectin is associated with high-grade progression of low-grade MALT lymphoma

Expression of adhesion molecule in low-grade B-cell mucosa-associated lymphoid tissue (MALT) lymphoma of the gastrointestinal tract has been reported in recent years, but these reports have primarily focused on low-grade gastrointestinal MALT lymphoma. In this study, we examined the lymphocytic homing receptor alpha4beta7 integrin, L-selectin, and VLA-4 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in low-grade lymphoma of the gastrointestinal tract and other organs such as the ocular adnexa and thyroid. We also observed changes in the expression pattern associated with high-grade transformation. Neoplastic cells in the gastrointestinal low-grade lymphoma and the low-grade component of high-grade MALT lymphoma were found to be alpha4beta7 integrin(+), L-selectin(+), whereas the gastrointestinal high-grade component and diffuse large B-cell lymphoma were found to be alpha4beta7 integrin(-), L-selectin(-). High endothelial venules in the gastric MALT lymphomas expressed MAdCAM-1. In the ocular adnexa low-grade MALT lymphoma, most cases were alpha4beta7 integrin(-), L-selectin(+); and in the thyroid, most cases of both low- and high-grade MALT lymphoma were alpha4beta7 integrin(-), L-selectin(-). These findings show that alpha4beta7 integrin and L-selectin may play an important role in the lymphocyte homing of gastrointestinal low-grade MALT lymphoma and in the loss of alpha4beta7 integrin expression throughout the course of high-grade progression.

[Behavior of Trp-P-1 and its metabolites in rat excreta]

To study of the behavior of Trp-P-1 and its metabolites in rat feces and urine, rats were orally administered with Trp-P-1 (750, 1,500 and 2,500 micrograms/rat), and excreted Trp-P-1 was analyzed using HPLC assay and bacterial mutagenicity assay. The extraction of Trp-P-1 from urine was performed by using the chloroform extraction method, and blue rayon was used for the extraction from feces. When Trp-P-1 was added to rat feces and urine, the recoveries of Trp-P-1 were 85.9 +/- 3.9% and 91.3 +/- 3.7%, respectively. The extracts of feces and urine from rats administered with Trp-P-1 were individually fractionated by thin layer chromatography on C18 gel. The major mutagenic zone corresponding to Trp-P-1 was found at Rf 0.09 in both extracts, while the feces extract gave two additional mutagenic zones at Rf 0.15 and 0.20. More than 97% of the fecal mutagenic activity was due to unchanged Trp-P-1. In rats administered with 750 micrograms of Trp-P-1, the amount of extracted Trp-P-1 and the number of His+ colonies induced by whole excreta were 81.6 +/- 7.1 micrograms (n = 6) and (432 +/- 77) x 10(4) for feces, and 28.7 +/- 4.9 micrograms and (171 +/- 28) x 10(4) for urine. The recoveries of Trp-P-1 in the feces and urine were 10.8 +/- 0.9% and 3.8 +/- 0.7% by HPLC analysis, and 11.1 +/- 2.0% and 4.4 +/- 0.7% by mutagenicity assay respectively. The results of the two assays seemed to show similar patterns of recovery.

Dual regulation of sphingosine 1-phosphate-induced phospholipase D activity through RhoA and protein kinase C-alpha in C2C12 myoblasts

Previous studies showed that in C2C12 cells, phospholipase D (PLD) and its known regulators, RhoA and protein kinase Calpha (PKCalpha), were downstream effectors in sphingosine 1-phosphate (SPP) signalling. Moreover, the role of PKC for SPP-mediated PLD activation and the requirement of PKCalpha for RhoA translocation were reported. The present results demonstrated that inactivation of RhoA, by overexpression of RhoGDP dissociation inhibitor (RhoGDI) as well as treatment with C3 exotoxin, attenuated SPP-stimulated PLD activity, supporting the involvement of RhoA in the stimulation of PLD activity by the bioactive lipid in C2C12 myoblasts. In addition, the effect of PKCalpha inhibitor Gö6976 on the SPP-induced PLD activation in myoblasts, where RhoA function was inactivated, was consistent with a dual regulation of the enzyme through RhoA and PKCalpha. Interestingly, the subcellular distribution of PLD isoforms, RhoA and PKCalpha, in SPP-stimulated cells supported the view that the functional relationship between the two PLD regulators, demonstrated to occur in SPP signalling, represents a novel mechanism of regulation of specifically localized PLD.

Vitamin B-6-supplemented diets compared with a low vitamin B-6 diet suppress azoxymethane-induced colon tumorigenesis in mice by reducing cell proliferation

Male ICR mice were examined for the effect of vitamin B-6 [pyridoxine (PN) HCl] on azoxymethane-induced colon tumorigenesis. Mice were fed the diets containing 1, 7, 14 or 35 mg PN HCl/kg for 22 wk, and given a weekly injection of azoxymethane (5 mg/kg body) for the initial 10 wk. Compared with the 1 mg PN HCl/kg diet, 7, 14 and 35 mg PN HCl/kg diets significantly suppressed the incidence and number of colon tumors, colon cell proliferation and expressions of c-myc and c-fos proteins. For some variables, 14 and 35 mg PN HCl/kg diets were more effective than the 7 mg/kg diet. Supplemental vitamin B-6 had no influence on the number of colon apoptotic cells. The results suggest that elevating dietary vitamin B-6 suppresses colon tumorigenesis by reducing cell proliferation.

Recombinant expression of perchloric acid-soluble protein reduces cell proliferation

Perchloric acid-soluble protein (PSP) may play an important role in the regulation of cellular physiological functions because it has been highly conserved throughout evolution; however, this role has not been well elucidated. In previous reports, we suggested that PSP regulates cell proliferation. In this study, we examined the effect of PSP expression on proliferation of the normal rat kidney cell line NRK-52E, the rat hepatocyte cell line RLN-10, and the rat hepatoma cell line dRLh-84. Cells transfected with pcDNA-sense-PSP (pcDNA-S-PSP) over-expressed PSP mRNA and protein, and cell proliferation of the transfected cells was suppressed compared with that of cells transfected with pcDNA-empty (pcDNA-E). Cell viability of pcDNA-S-PSP-transfected cells was similar to that of pcDNA-E-transfected cells. Thus, over-expression of PSP suppresses cell proliferation without any influence on cell viability. These findings are the first to report an inhibitory activity of PSP on cell proliferation.

Thoracic epidural bupivacaine attenuates supraventricular tachyarrhythmias after pulmonary resection

Supraventricular tachyarrhythmias after pulmonary surgery are well described. Some investigators suggest that tachyarrhythmias after thoracic operations may result from the relative sympathotonic status produced by injury to the cardiac parasympathetic nerves. We examined whether postoperative thoracic sympathetic blockade by thoracic epidural bupivacaine might reduce the tachyarrhythmias after pulmonary resection. Fifty patients with lung cancer were randomized to receive epidural bupivacaine (Group B) or epidural morphine (Group M). Patients in Group B were given 6 to 10 mL of 0.25% bupivacaine epidurally, followed by epidural infusion at 3 to 5 mL/h for 3 days, and patients in Group M were given 2 to 3 mg morphine epidurally, followed by morphine infusion at a rate of 0.2 mg/h. Tachyarrhythmias were diagnosed by using the continuous heart rate trend and arrhythmia trend with a central monitoring system. Postoperative analgesia was not statistically different between groups. However, the incidence of postoperative tachyarrhythmias in Group B was significantly less than in Group M (1 of 23 vs 7 of 25, P = 0.0497, Fisher's exact test). The continuous infusion of thoracic epidural bupivacaine can reduce supraventricular tachyarrhythmias compared with epidural morphine infusion, presumably because of attenuation of the sympathotonic status after pulmonary resection.

IMPLICATIONS

We examined whether postoperative thoracic sympathetic blockade by thoracic epidural bupivacaine after pulmonary resection might reduce the tachyarrhythmias that may result from the relative sympathotonic status produced by injury to the cardiac parasympathetic nerves. The continuous infusion of thoracic epidural bupivacaine was shown to reduce supraventricular tachyarrhythmias.

Renal artery aneurysm causing hydronephrosis

A 42-year-old man presented with left hydronephrosis incidentally discovered on abdominal echogram during a routine health examination. Color Doppler ultrasonography, intravenous pyelography and angiography revealed a non-calcified renal artery aneurysm of 30 mm in size compressing the pyeroureteral junction and causing hydronephrosis. Three-dimensional computed tomography (3-D CT) using spiral CT clearly displayed the aneurysm located at the first bifurcation of the left renal artery and involving the anterior segmental artery. Decompression was successfully obtained via in situ revascularization of the renal artery after aneurysmectomy. A literature search revealed 12 cases of renal artery aneurysm causing hydronephrosis reported in Japan, although only three cases were documented in other countries, and these reports are reviewed. Use of 3-D CT for evaluation of renal artery aneurysm is advocated.

Modulation of dendrodendritic interactions and mitral cell excitability in the mouse accessory olfactory bulb by vaginocervical stimulation

When female mice are mated, they form a memory to the pheromonal signal of their male partner. The neural changes underlying this memory occur in the accessory olfactory bulb, depend upon vaginocervical stimulation at mating and involve changes at the reciprocal synapses between mitral and granule cells. However, the action of vaginocervical stimulation on the reciprocal interactions between mitral and granule cells remains to be elucidated. We have examined the effects of vaginocervical stimulation on paired-pulse depression of amygdala-evoked field potentials recorded in the external plexiform layer of the accessory olfactory bulb (AOB) and the single-unit activity of mitral cells antidromically stimulated from the amygdala in urethane-anaesthetized female mice. Artificial vaginocervical stimulation reduced paired-pulse depression (considered to be due to feedback inhibition of the mitral cell dendrites from the granule cells via reciprocal dendrodendritic synapses) recorded in the AOB external plexiform layer. As would be expected from this result, vaginocervical stimulation also enhanced the spontaneous activity of a proportion of the mitral cells tested. These results suggest that vaginocervical stimulation reduces dendrodendritic feedback inhibition to mitral cells and enhances their activity.

Cost effectiveness of reducing dioxin emissions from municipal solid waste incinerators in Japan

The main sources of dioxin emissions are municipal solid waste incinerators. The Japanese national government has set an emission standard for dioxins to reduce dioxin exposure levels. In this study, cost-effectiveness analyses are carried out regarding countermeasures that were recently taken and are being taken at municipal solid waste incinerators in Japan. Annual costs were estimated by telephone survey and model calculations. Annual decrease in the incidence of cancer was estimated in three steps. First, the annual decrease in the volume of dioxin emissions was estimated. Next, using a mathematical model, the annual decrease in human exposure was estimated. Finally, the annual decrease in the incidence of cancer was estimated by applying the cancer slope factor. When annual costs are divided by the annual number of life-years saved, cost per life-year saved (CPLYS) was obtained. CPLYS was estimated to be 7.9 million yen for emergency countermeasures and 150 million yen for long-term countermeasures. However, it must be noted that these obtained CPLYSs are highly dependent on the cancer slope factor and should be considered as an upper limit since there may be a cancer effect threshold.

Purification, characterization and developmental expression of rat brain PSP protein

We have isolated a perchloric acid-soluble protein designated as B-PSP1 from the postmitochondria supernatant fraction of rat brain. It was purified by gel filtration and anti-PSP1 affinity chromatography. Immunoblotting, peptide mapping, partial amino acid sequencing and reverse transcriptase-polymerase chain reaction showed that the amino acid sequence of B-PSP1 was identical with that of PSP isolated from rat liver. B-PSP1 was expressed in all regions including frontal cortex, posterior cortex, cerebellum, hippocampus, olfactory bulb, striatum, thalamus, midbrain, entorhinal cortex, pons, medulla and spinal cord. Immunohistochemical study showed that the expression of B-PSP1 was observed in ependymal cells of choroid plexus and glial cells of the other region. The expression of B-PSP1 in brain increased gradually from the first day to the 60th day of postnatal age, but the expression of B-PSP1 was slower than that of GFAP which is a marker protein of glial cells. The expression of PSP may be related to the cellular function rather than the developmental regulation of the glial cells. Thus, our findings are the first report on the presence of a PSP in rat brain which may be involved in the regulation of cellular function.

Aortic valve repair of congenital bicuspid aortic valve associated with aneurysm of the ascending aorta

Two unusual cases of congenital bicuspid aortic valve associated with aneurysm of the ascending aorta are reported. One patient with a 7-cm ascending aortic dilatation and aortic regurgitation (AR) (II/IV), and another with a 6-cm ascending aorta and AR (III/IV), presented for treatment. Replacement of the ascending aorta and aortic valve repair were performed in both cases. Aortic valve repair included resection of the raphe, leaflet plication and subcommissural annuloplasty. Both patients had satisfactory results in the early postoperative period. Despite the promising outcomes after surgery in these patients, long-term changes in valve function and durability remain unknown. Additional close observation and monitoring are required before the procedure can be recommended as the standard of care.

Activation of GABA(A) receptors in the accessory olfactory bulb does not prevent the formation of an olfactory memory in mice

When female mice are mated, they form a memory to the pheromonal signal of their male partner. The neural mechanisms underlying this memory involve changes at the reciprocal dendrodendritic synapses between glutamatergic mitral cells and gamma-aminobutyric acid (GABA)-ergic granule cells in the accessory olfactory bulb (AOB). Blockade of GABA(A) receptors in the AOB leads to the formation of an olfactory memory. In an attempt to disrupt memory formation at mating, we used local infusions of the GABA(A) receptor agonist muscimol into the AOB during the critical period for memory formation. Muscimol across a wide range of doses (1-1000 pmol) did not prevent memory formation. The resistance of this memory to GABA(A) receptor activation may reflect the complexity of synaptic microcircuits in the AOB.

Completion pneumonectomy for recurrent or second primary lung cancer

OBJECTIVE

We studied 8 patients undergoing completion pneumonectomy for recurrent or second primary lung cancer.

METHODS

Subjects were men who averaged 62 years of age. Of these 6 had p-stage I, and 2 p-stage II disease at initial operation. At the second operation, we diagnosed 3 with second primary lung cancer and 5 with recurrent lung cancer. We predicted postoperative pulmonary function by calculating the predicted forced expiratory volume in 1.0 second (FEV1.0) from residual numbers of subsegments after completion pneumonectomy. All predicted FEV1.0 in our 8 cases ranged from 544 to 926 (773 +/- 144) ml/m2.

RESULTS

Six patients experienced postoperative complications and morbidity was 75%. One patient undergoing completion sleeve pneumonectomy after radiation therapy for local carina recurrence died on 7th postoperative day due to anastomotic dehiscence and pneumonia. Overall operative mortality was 12.5% (1/8). Four remain alive and actuarial 5-year survival was 37.5%.

CONCLUSIONS

Careful consideration is needed in determining operative indications for completion pneumonectomy for patients after radiation therapy. Patients with recurrent squamous cell carcinoma who have p-stage I disease at initial operation and those with second primary lung cancer and p-stage I or II disease can expect relatively a long-term survival, and we concluded that completion pneumonectomy could be conducted in these cases with a satisfactory prognosis.

Regular overtime and cardiovascular functions

It was concluded that there was sufficient evidence about a possible link between long working hours particularly exceeding 50 a week and the risk of significant health outcomes, including cardiovascular disease from literature review by Spurgeon et al.. This study was conducted to find out the single effect of regular overtime work on the cardiovascular functions through objective biological indices such as blood pressure or heart rate variability. We conducted a field survey of 238 male engineers who were working at the department of research & development of three electronics manufacturing companies in S. Korea. The field survey consisted of (1) self-report questionnaire (working hours and health conditions, and fatigue) and (2) measurements of blood pressure and heart rate variability. By multivariate analyses we could show the relationship between overtime work and some cardiovascular functions after controlling the effects of major confounders such as age and sleeping hours, which were pointed out by Iwasaki et al. (1998) and Sasaki et al. (1999). Especially, low frequency component (power in the low frequency range, 0.04-0.15 Hz) of the heart rate variability during work might be used as early objective biological indices for chronic effect of regular overtime work on cardiovascular functions. However, we should confirm those effect through the well-designed prospective study.

Effects of antisense oligodeoxynucleotides against opioid receptors on the receptor mRNA contents

It was demonstrated in the previous study that the microinjection of antisense oligodeoxynucleotide (AS ODN) against mu-opioid receptor (MOR) into periaqueductal gray (PAG) of rat brain selectively decreased the MOR mRNA content in PAG, and the decrease in MOR mRNA content was enhanced by pretreatment of the PAG with MOR AS ODN. In the present investigation, effects of the pretreatment of PAG with AS ODN against kappa- or delta-opioid receptor (KOR or DOR) on the decrease in the MOR mRNA content induced by MOR AS ODN were examined. Both KOR and DOR AS ODNs significantly decreased the target mRNA contents, while they did not significantly change MOR mRNA content. The decrease in MOR mRNA content induced by MOR AS ODN, however, was significantly enhanced by the pretreatment of PAG with either KOR or DOR AS ODNs. Results show that the AS ODN has both the specific target mRNA decreasing action and the nonspecific enhancing action on the AS-induced decrease in the mRNA content.

Microscopic polyangiitis associated with sinobronchial syndrome

A woman with a long history of chronic bronchitis and chronic sinusitis, i.e., sinobronchial syndrome, was admitted with a fever. Radiologically, there were areas of longstanding consolidation in both lungs, with areas of active inflammation demonstrated by gallium-67 scintigraphy. Antineutrophil cytoplasmic antibody specific for myeloperoxidase was highly positive. Pulmonary hemorrhage and hematuria occurred 2 weeks after admission and responded to steroid therapy. However, the patient died of pneumonia. An autopsy revealed systemic necrotizing vasculitis affecting multiple organs, consistent with microscopic polyangiitis. The vasculitis might have been caused by the chronic inflammation in the lungs associated with sinobronchial syndrome.

Analysis of c-myc DNA amplification in non-small cell lung carcinoma in comparison with small cell lung carcinoma using polymerase chain reaction

Previous studies of c-mvc DNA amplification in lung cancer have focused primarily on analysis of small cell carcinoma or its tumor cell lines. There are few data about c-myc DNA amplification in histological types of lung cancer other than small cell carcinoma. Therefore the present study was conducted to investigate c-myc oncogene amplification in non-small cell lung carcinoma. We studied 46 lung tumor specimens for c-myc DNA amplification (15 adenocarcinomas, 15 squamous cell carcinomas, 6 large cell carcinomas, and 10 small cell carcinomas). Polymerase chain reaction, digoxigenin DNA labeling, and electrophoresis were utilized to investigate the c-myc copy number in the lung tumor specimens. The c-myc copy number of non-small cell carcinoma ranged from 1.5 to more than 20.0 in adenocarcinoma and squamous cell carcinoma, and from 6.0 to 12.0 in large cell carcinoma. That of small cell carcinoma ranged from 1.8 to 12.0. The c-myc copy number of non-small cell carcinoma was significantly higher than that of small cell carcinoma (Wilcoxon rank sum test, Z=2.06 P=0.040). However, the differences in c-myc copy number among these four histological types were not statistically significant. Amplification of c-myc (more than 4 copies) was observed not only in small cell carcinoma but also in nonsmall cell carcinoma at similarly high frequency (12/15 in adenocarcinoma and squamous cell carcinoma, 6/6 in large cell carcinoma, and 9/10 in small cell carcinoma).

Reduction of intraocular pressure by topical administration of an inhibitor of the Rho-associated protein kinase

PURPOSE

Rho-associated coiled coil-forming protein kinase (ROCK) is a downstream target of a small GTPase, Rho. The kinase has been reported to regulate actomyosin-based contractility of smooth muscles by modulation of myosin phosphatase activity. Contractility of ciliary muscle could be implicated in regulation of intraocular pressure while that of ocular vessels could affect blood flow to retina. The present study has been performed to investigate the effect of a ROCK inhibitor on intraocular pressure in rabbits.

METHODS

An inhibitor of ROCK, Y-27632, was dissolved in an ophthalmic solution and topically administered to the eye of a Japanese white rabbit. Intraocular pressure was measured by pneumatonography (n = 12, 24 eyes). Constriction of ciliary muscle was measured by the Magnus method using 12 eyes.

RESULTS

Topical application of 0.1 and 0.03% Y-27632 significantly decreased the intraocular pressure, with maximum decreases of 5.3 and 4.3 mm Hg after 90 minutes compared with the control eye. Y-27632 inhibited the carbachol-induced constriction of rabbit ciliary muscle.

CONCLUSIONS

The ROCK inhibitor reduced intraocular pressure in rabbits by topical instillation. The inhibitor relaxed the excised ciliary muscle which was previously constricted by carbachol suggesting that the inhibitor acts to increase the uveoscleral outflow. Our results suggest that the ROCK inhibitor is a promising treatment for glaucoma therapy in the next generation.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1999). III. Secular changes in susceptibility]

The bacteria (Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa) isolated from patients diagnosed as having urinary tract infections (UTIs) in 9 institutions in Japan were supplied between the period of August 1999 to July 2000. Then, the susceptibilities of these bacteria to various antimicrobial agents were examined and the results were compared with those obtained between 1991 and 1998. Comparison was made by classifying strains isolated from patients into those with uncomplicated UTIs and those with complicated UTIs (including with or without indwelling catheter). About E. faecalis, increase of low sensitive strains noted in the former year showed a decreasing tendency, however, one strain each with MIC of 4 micrograms/ml to vancomycin (VCM) was detected in patients with both uncomplicated and complicated UTIs. As for S. aureus, many sensitive strains to cephems, imipenem (IPM) and VCM were noted, and each MIC50 was better than that in the former years. S. aureus strains showing low susceptibility to arbekacin (ABK) were detected in patients with complicated UTIs in this year as well as in the former year, and one strain each with MIC of 16 micrograms/ml and 32 micrograms/ml was detected. Susceptibilities of E. coli were effective to all drugs except for penicillins and minocycline (MINO). Decrease of low sensitive strains was also noted in all drugs except for quinolones. Each MIC90 of ciprofloxacin (CPFX) and sparfloxacin (SPFX) in patients with complicated UTIs against E. coli was 3 degrees classes lower than that in patients with uncomplicated UTIs. As for Klebsiella pneumoniae, decrease of low sensitive strains to cephems was noted in patients with uncomplicated UTIs in 1998. In 1999, low sensitive strains decreased also in patients with complicated UTIs, and few were detected. Susceptibilities of K. pneumoniae to quinolones were effective as compared with those in the former years with the MIC80s of 0.125 microgram/ml or below without detection of low sensitive strains. One low sensitive strain of K. pneumoniae with MIC of 8 micrograms/ml was detected for gentamicin (GM). Susceptibilities of P. aeruginosa to carbapenems were notable. The MIC90 of meropenem (MEPM) and IPM was 4 micrograms/ml each which was 2 degrees better than that in 1998. Resistant P. aeruginosa strains to other drugs except for monobactams decreased in 1999.

Differential expression of mRNAs for sialyltransferase isoenzymes induced in the hippocampus of mouse following kindled seizures

Sialic acids play important roles in various biological functions. In the brain, evidence suggests that sialylation of glycoproteins and glycolipids affects neural plasticity. While the 18 sialyltransferase isoenzymes (STs) identified to date synthesize individual sialyl-oligosaccharide structures, they each exhibit activity toward more than one substrate and can overlap in their specificity. Therefore, the distribution of STs is a secondary factor in the study of specific sialylation. Here, seven STs; ST3Gal I-IV, ST8Sia IV, ST6Gal I and ST6GalNAc II, the expressions of which were identified in the adult hippocampus by RT-PCR, showed diverse localization patterns in the hippocampus on in situ hybridization, suggesting that the individual cells expressed relevant STS: Furthermore, to assay activity-related changes in ST expression, we used amygdaloid-kindling among models of neural plasticity. Differential expression of the STs participating in the kindling, notably, up-regulation of ST3Gal IV and ST6GalNAc II mRNAs, and down-regulation of ST3Gal I and ST8Sia IV mRNAs, were observed in the hippocampus following kindled seizures. These results indicate that ST expressions are regulated by physiological activity and may play a role in neural plasticity.

Distal airspace enlargement in the fawn-hooded rat: influences of aging and alveolar wall destruction

BACKGROUND

A recent study has revealed that the peripheral airspace in the lungs of the fawn-hooded rat (FHR) is enlarged. However, morphological and functional factors of the FHR lung have not been fully investigated.

OBJECTIVE

The purpose of our study was to examine the structural and functional changes in the FHR lung and to investigate the influence of aging on this process. Furthermore, morphological and functional measurements of the lungs of FHRs (4-48 weeks of age) were performed and the results compared with those of age-matched Wistar control rats (WCRs).

METHODS

All animals were studied under controlled conditions, and morphological and functional changes of the lungs were examined. Measurements of body and lung weights were recorded, and the lungs were subjected to morphological evaluation. Morphological measurements: mean linear intercept (MLI) and destructive index were determined. Functional evaluation of the lungs: total lung capacity, pressure-volume curve, and exponential constant (K) which describes the shape of the curve were analyzed. In addition, right ventricular hypertrophy measurements were performed to assess the severity of pulmonary hypertension. Statistical analysis was performed using the unpaired t test, analysis of variance, and the Fisher post hoc test (p < 0.05).

RESULTS

Morphological analysis revealed a significant increase in airspace size (MLI) in all FHRs as compared with the WCRs which was evident from an early age (4 weeks). The increase in MLI did not progress age dependently in the FHR, whereas a tendency for an age-dependent increase in MLI was observed in the WCR. The destructive index measurements revealed that the increase in MLI of FHR was not accompanied by alveolar wall destruction. Concerning the functional examination, a leftward and upward shift of the pressure-volume curve was observed in the FHRs as compared with the WCRs at all ages. As compared with the WCRs, a higher K value was observed in all FHRs which was evident from an early age (4 weeks). Age-dependent changes similar to those in MLI were observed in the K in both rat strains.

CONCLUSIONS

The results of our study suggest that FHRs manifest characteristics of distal airspace enlargement accompanied by increased lung distensibility without alveolar wall destruction at an early age and that the changes do not progress age dependently. Neither an accelerated aging process nor destruction of the alveolar walls appears to be the mechanism responsible for the enlarged airspace in this rat strain.

Sharp spectral lines observed in gamma-ray ionized parahydrogen crystals

We have observed sharp infrared spectral lines ( Deltanu approximately 60 MHz FWHM) in gamma-ray ionized para- H2 crystals. The lines are assigned to the Q1(0) transition of H2 near H+3 and H-, which becomes optically active and Stark shifted by the Coulomb fields of the ions. A simple model calculation gives a spectrum which agrees approximately with the observation. The spectrum stays the same over many days, demonstrating the stability of the ionized system. The remarkable sharpness and reproducibility of the line positions indicate uniformity of the local structure surrounding the charges.

Serine proteinase inhibitor 3 and murinoglobulin I are potent inhibitors of neuropsin in adult mouse brain

Extracellular serine protease neuropsin (NP) is expressed in the forebrain limbic area of adult brain and is implicated in synaptic plasticity. We screened for endogenous NP inhibitors with recombinant NP (r-NP) from extracts of the hippocampus and the cerebral cortex in adult mouse brain. Two SDS-stable complexes were detected, and after their purification, peptide sequences were determined by amino acid sequencing and mass spectrometry, revealing that target molecules were serine proteinase inhibitor-3 (SPI3) and murinoglobulin I (MUG I). The addition of the recombinant SPI3 to r-NP resulted in an SDS-stable complex, and the complex formation followed bimolecular kinetics with an association rate constant of 3.4 +/- 0.22 x 10(6) M(-1) s(-1), showing that SPI3 was a slow, tight binding inhibitor of NP. In situ hybridization histochemistry showed that SPI3 mRNA was expressed in pyramidal neurons in the hippocampal CA1-CA3 subfields, as was NP mRNA. Alternatively, the addition of purified plasma MUG I to r-NP resulted in an SDS-stable complex, and MUG I inhibited degradation of fibronectin by r-NP to 24% at a r-NP/MUG I molar ratio of 1:2. Immunofluorescence histochemistry showed that MUG I localized in the hippocampal neurons. These findings indicate that SPI3 and MUG I serve to inactivate NP and control the level of NP in adult brain, respectively.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1999). II. Background of patients]

Five-hundred forty four bacterial strains isolated from 412 patients diagnosed as having urinary tract infections (UTIs) in 9 institutions in Japan were supplied between the period of August 1999 to July 2000. Then, the clinical background of patients were investigated such as sex, age and type of infections, infections and kind of bacteria, frequency of isolation of bacteria by age and infections, bacteria and infections by timing of administration of antibiotics, and bacteria and infections by surgical procedures. About the relationship between age and sex of patients and type of infections, the number of male patients aged less than 50 years was few, and complicated UTIs without indwelling catheter was the most frequent. In females, the number of patients aged less than 20 years was few. Complicated UTIs without indwelling catheter was the most frequent among female patients aged between 40 to 59 years, in other age groups, uncomplicated UTIs was most frequent. As for type of infections and kind of bacteria, Escherichia coli decreased when the infections became complicated, and Pseudomonas aeruginosa and Enterococcus faecalis increased when the infection became complicated. Considering this result by age of patients, isolation frequency of E. coli was gradually decreased with aging in patients aged more than 20 years with uncomplicated UTIs or complicated UTIs without indwelling catheter. The isolation frequencies of E. faecalis and Staphylococcus aureus were gradually increased with aging in complicated UTIs without indwelling catheter. In patients with complicated UTIs with indwelling catheter, there was no difference between age group, and P. aeruginosa and E. faecalis were frequently isolated. As for type of causative organisms in UTIs before and after the administration of antibiotics, the isolation of bacteria was remarkably decreased after administration in patients with uncomplicated UTIs and complicated UTIs without indwelling catheter. E. coli decreased after administration of antibiotics, and P. aeruginosa and E. faecalis increased after administration in patients with all infections. As for type of causative organisms in UTIs and surgical procedures, E. coli were more frequently isolated in patients with uncomplicated UTIs when surgical procedures were experienced. Also, Klebsiella spp. and E. faecalis were more frequently isolated in patients with surgical procedures. However, in complicated UTIs, type of causative organisms had no relationship with surgical procedures.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1999). I. Susceptibility distribution]

The bacterial strains isolated from patients diagnosed as having urinary tract infections (UTIs) in 9 institutions in Japan were supplied between the period of August 1999 to July 2000. Then, the susceptibilities of them to many kinds of antimicrobial agents were investigated. The number of them were 499 strains. The breakdown of these strains was Gram-positive bacteria as 31.3% and Gram-negative bacteria as 68.7%. Susceptibilities of these bacteria to antimicrobial agents were as follows; vancomycin (VCM), ampicillin (ABPC) and imipenem (IPM) showed strong activities against Enterococcus faecalis. The increase of low-susceptible strains which was noticed in the former year showed a slight recovery in this year. VCM showed a strong activity against MRSA preventing growth of all strains with 1 microgram/ml. In addition, the activity of arbekacin (ABK) was also strong with the MIC90 of 2 micrograms/ml against MRSA. However, MSSA and MRSA showing low susceptibilities were detected in one strain each (MIC: 16 micrograms/ml and 32 micrograms/ml, respectively). Carbapenems showed high activities against Citrobacter freundii and Escherichia coli. Meropenem (MEPM) prevented growth of all strains within 0.125 microgram/ml. Quinolone resistant E. coli decreased in this year compared with those in the last year, that percentage was less than 5%. Almost all drugs showed strong activities against Klebsiella pneumoniae and Proteus mirabilis. MEPM and carumonam (CRMN) prevented growth of all strains within 0.125 microgram/ml. On the other hand, one strain of K. pneumoniae showing resistance to cefaclor (CCL) and one strain of P. mirabilis showing low susceptibility to most of cephems were detected. Against Pseudomonas aeruginosa, almost drugs were not so active. The MIC90s of carbapenems were 8 micrograms/ml and those of all other drugs were more than 16 micrograms/ml.

Mechanisms and mediators of psychological stress-induced rise in core temperature

OBJECTIVE

Despite numerous case reports on "psychogenic fever," it remains uncertain how psychological stress raises core temperature and whether the rise in core temperature is a real fever or a hyperthermia. This article reviews studies on the psychological stress-induced rise in core temperature (PSRCT) in animals with the aim to facilitate studies on the mechanisms of so-called psychogenic fever in humans.

METHODS

To address this question, we reviewed the mechanisms and mediators of the PSRCT and classic conditioning of the fever response in animals.

RESULTS

The PSRCT is not due to the increased locomotor activity during stress, and the magnitude of the PSRCT is the same in warm and cold environments, indicating that it is a centrally regulated rise in temperature due to an elevated thermoregulatory "set point." The PSRCT caused by conventional psychological stress models, such as open-field stress, is attenuated by cyclooxygenase inhibitors, which block prostaglandin synthesis. On the other hand, the PSRCT elicited by an "anticipatory anxiety stress" is not inhibited by cyclooxygenase inhibitors but by benzodiazepines and serotonin Type 1A receptor agonists. The febrile response can be conditioned to neutral stimuli after paired presentation with unconditioned stimuli such as injection of lipopolysaccharide, a typical pyrogen.

CONCLUSIONS

Most findings indicate that the PSRCT is a fever, a rise in the thermoregulatory set point. The PSRCT may occur through prostaglandin E2-dependent mechanisms and prostaglandin E2-independent, 5-HT-mediated mechanisms. The febrile response can be conditioned. Thus, these mechanisms might be involved in psychogenic fever in humans.

Enantioselective synthesis and absolute configuration of (−)-1-(benzofuran-2-yl)-2-propylaminopentane, ((−)-BPAP), a highly potent and selective catecholaminergic activity enhancer

Enantioselective synthesis and absolute configuration of (-)-1-(benzofuran-2-yl)-2-propylaminopentane ((-)-BPAP), which is a highly potent and selective catecholaminergic activity enhancer (CAE) substance, are described. The synthetic approach consists of the coupling reaction of benzofuran with (R)-N-tosyl-2-propylazirizine or (R)-N-methoxy-N-methylnorvaliamide, followed by appropriate modifications of the resulting coupling products. As the results, (-)-BPAP turned out to have the R configuration, which was finally confirmed by X-ray crystallographic analysis.

Partial tolerance of subcutaneously transplanted xenogeneic tumour cell graft by Fas-mediated immunosuppression

Certain anti-Fas antibodies, such as RMF2, induce apoptosis of Fas-expressing cells. We applied the Fas/anti-Fas system to induce killing of Fas-expressing immunocytes with resultant immunosuppression. W7TM-1 tumour cells, a rat T-cell line, were inoculated subcutaneously in BALB/c mice and tumour growth was monitored in untreated mice and in mice treated with RMF2. Prior to treatment with RMF2, we examined the expression of Fas in isolated splenocytes and in tumour-infiltrating lymphocytes by flow cytometry and immunohistochemistry, respectively. There was a remarkable increase in Fas-positive lymphocytes, including natural killer (NK) cells, among splenocytes at day 5 after tumour cell inoculation. The number of Fas-positive infiltrating lymphocytes also increased markedly, from day 5 to day 10. We then examined whether RMF2 could induce apoptosis of Fas-positive activated lymphocytes isolated from the spleen at day 5 in vitro. Terminal deoxy (d) -UTP nick end labelling (TUNEL) and Annexin V staining methods showed apoptosis of isolated cells when incubated with RMF2, and typical apoptotic features were confirmed by 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) staining. Furthermore, suppression of cellular and humoral immunity was noted in RMF2-treated mice by mixed lymphocyte reaction and assay of serum levels of immunoglobulin G, respectively. Finally, treatment of animals with RMF2 daily from day 5 to day 9 could maintain the tumour size, while the tumour mass began to diminish in untreated mice immediately after reaching a maximum size. We confirmed the enhancing effects of long-term treatment with RMF2, through the induction of immunosuppression, on the growth of unvascularized xenogeneic tumour cell grafts.

Defect in human myocardial long-chain fatty acid uptake is caused by FAT/CD36 mutations

Because of the importance of long-chain fatty acids (LCFAs) as a myocardial energy substrate, myocardial LCFA metabolism has been of particular interest for the understanding of cardiac pathophysiology. Recently, by using radiolabeled LCFA analogues, myocardial LCFA metabolism has been clinically evaluated, which revealed a total defect of myocardial LCFA accumulation in a small number of subjects. The mechanism for the cellular LCFA uptake process is still disputable, but recent results suggest that fatty acid translocase (FAT)/CD36 is a transporter in the heart. In the present study, we analyzed mutations and protein expression of the FAT/CD36 gene in 47 patients who showed total lack of the accumulation of a radiolabeled LCFA analogue in the heart. All the patients carried two mutations in the FAT/CD36 gene, and expression of the FAT/CD36 protein was not detected on either platelet or monocyte membranes. Our results showed the link between mutations of the FAT/CD36 gene and a defect in the accumulation of LCFAs in the human heart.

Hypothalamic mechanisms of pain modulatory actions of cytokines and prostaglandin E2

A decrease and subsequent increase in nociceptive threshold in the whole body are clinical symptoms frequently observed during the course of acute systemic infection. These biphasic changes in nociceptive reactivity are brought about by central signal substances induced by peripheral inflammatory messages. Systemic administration of lipopolysaccharide (LPS) or interleukin-1 beta (IL-1 beta), an experimental model of acute infection, may mimic the biphasic changes in nociception, hyperalgesia at small doses of LPS, and IL-1 beta and analgesia at larger doses. Our behavioral and electrophysiological studies have revealed that IL-1 beta in the brain induces hyperalgesia through the actions of prostaglandin E2 (PGE2) on EP3 receptors in the preoptic area and its neighboring basal forebrain, whereas the IL-1 beta-induced analgesia is produced by the actions of PGE2 on EP1 receptors in the ventromedial hypothalamus. An intravenous injection of LPS (10-100 micrograms/kg) produced hyperalgesia only during the period before fever develops and was abolished by microinjection of NS-398 (an inhibitor of cyclooxygenase 2) into the preoptic area, but not into the other areas in the hypothalamus. The hyperalgesia induced by the cytokines PGE2 and LPS may explain the systemic hyperalgesia clinically observed in the early phase of infectious diseases, which probably warns the organisms of infection before the full development of sickness symptoms. The switching of nociception from hyperalgesia to analgesia accompanied by sickness symptoms may reflect changes in the host's strategy for fighting microbial invasion as the disease progresses.

Expression and in vitro modification of parathyroid hormone-related protein (PTHrP) and PTH/PTHrP-receptor in human myeloma cells

To elucidate the role of PTHrP in myeloma, we examined the expression levels of PTHrP and its receptor in human myeloma cell lines and clinical specimens from 13 myeloma cases. In vitro modification of PTHrP expression and production induced by TGF-beta and PMA in PTHrP expressing myeloma cell lines was also investigated. PTHrP expression was detected in six out of seven myeloma cell lines with an inverse correlation with the expression of its receptor, and in 10 out of 13 clinical specimens in varying degrees. The PTHrP expression and secretion into culture medium were enhanced by supplemental TGF-beta and PMA. PMA also seemed to affect PTHrP upregulation via TGF-beta activation. The fundamental role of PTHrP in bone lesions and hypercalcemia in myeloma may be important to consider even during the initial phase of the disease and particularly in the progression of bone complications with hypercalcemia.

Lower percentage of CD56+ cells associated with long working hours

In a study of 142 Japanese men from a cross-section of the workforce of a technology development company, we found that the percentage of CD56+ cells was inversely correlated with the number of hours worked per week. A low CD56+ cell percentage was associated with longer weekly working hours and shorter daily sleeping hours.

An animal model for human EBV-associated hemophagocytic syndrome: herpesvirus papio frequently induces fatal lymphoproliferative disorders with hemophagocytic syndrome in rabbits

Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis. However, the animal model for EBV-AHS has not been developed. We reported the first animal model for EBV-AHS using rabbits infected with EBV-related herpesvirus of baboon (HVP). Eleven of 13 (85%) rabbits inoculated intravenously with HVP-producing cells developed fatal lymphoproliferative disorders (LPD) between 22 and 105 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in nine of these 11 rabbits. The peroral spray of cell-free HVP induced the virus infection with increased anti-EBV-viral capsid antigen-IgG titers in three of five rabbits, and two of these three infected rabbits died of LPD with HPS. Autopsy revealed hepatosplenomegaly and swollen lymph nodes. Atypical lymphoid T cells expressing EBV-encoded small RNA-1 infiltrated diffusely in many organs, frequently involving the lymph nodes, spleen, and liver. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by polymerase chain reaction or Southern blot analysis. Reverse transcriptase-polymerase chain reaction revealed both HVP-EBNA1 and HVP-EBNA2 transcripts, suggesting latency type III infection. These data indicate that the high rate of rabbit LPD with HPS induction is caused by HVP. This system is useful for studying the pathogenesis, prevention, and treatment of human EBV-AHS.

Apparent re-emergence of serotype G9 in 1995 among rotaviruses recovered from Japanese children hospitalized with acute gastroenteritis

Serotype G9 rotaviruses have been detected in about 0.5% of the circulating strains worldwide. However, G9 strains emerged globally in the middle of the 90s and thereafter. A rotavirus, contained in stool specimen 95H115, possessing a G9 VP7 emerged in Japan in the 1994-1995 season for the first time after a 9-year interval since prototype G9 strains AU32 and F45 were discovered in the 1985-1986 season. In comparison with other G9 VP7 genes thus far published, the sequencing of the VP7 genes of AU32 and 95H115 revealed that the 95H115 VP7 gene did not directly evolve from the AU32 VP7 gene but was much more closely related to the contemporary G9 VP7 genes found in the United States of America. Thus, recently emerging G9 VP7 genes were not direct descendants of the VP7 genes of the prototype strains in the 80s, rather they evolved independently into 4 phylogenetic clusters from a common ancestor.