Smad7 is induced by norepinephrine and protects rat hepatocytes from activin A-induced growth inhibition

Activin A induces growth arrest of rat hepatocytes in vitro and in vivo. The alpha(1)-adrenergic agonist, norepinephrine (NE), enhances epidermal growth factor-stimulated DNA synthesis and inhibits activin A-induced growth inhibition, but the mechanisms of these actions are unclear. Smad proteins have recently been identified as intracellular signaling mediators of transforming growth factor-beta family members. In the present study, we explored how NE modulates the Smad signaling pathway in rat cultured hepatocytes. We demonstrate that NE inhibits activin A-induced nuclear accumulation of Smad2/3 and that NE rapidly induces inhibitory Smad7 mRNA expression. Infection of Smad7 adenovirus into rat hepatocytes inhibited activin A-induced nuclear accumulation of Smad2/3, enhanced epidermal growth factor-stimulated DNA synthesis, and abolished the growth inhibitory effect of activin A. We also demonstrated that the induction of Smad7 by NE is dependent on nuclear factor-kappa B (NF-kappa B). The amount of active NF-kappa B complex rapidly increased after NE treatment. Preincubation of the cells with an NF-kappa B pathway inhibitor N-tosyl-l-phenylalanine chloromethyl ketone or infection of the cells with an adenovirus expressing an I kappa B super-repressor (Ad5I kappa B) abolished the NE-induced Smad7 expression. These results indicate a mechanism of transmodulation between the Smad and trimeric G protein signaling pathways in rat hepatocytes.

Significantly rapid relief from steroid-resistant nephrotic syndrome by LDL apheresis compared with steroid monotherapy

Rapid amelioration of hypercholesterolemia by LDL apheresis (LDL-A) was performed for long-standing nephrotic syndrome (NS) with hyperlipidemia due to focal segmental glomerulosclerosis (FGS) and the clinical data and prognosis were compared between LDL-A-treated and nontreated groups. Seventeen steroid-resistant NS patients treated with LDL-A (LDL-A group) and 10 NS patients treated with steroids only (steroid-monotherapy (SM) group) were compared. Serum cholesterol and phospholipid levels were significantly lowered only in the LDL-A group (p < 0.01, respectively). The LDL-A group showed a significant decrease of urinary protein (UP, p < 0.01) and increase of serum albumin (p < 0.05). Average time needed to achieve a decrease of UP to less than nephrotic range (< 3.5 g/day) was significantly shorter in the LDL-A group than in the SM group (p < 0.01). Although this is not a prospective study, it is highly expected that a rapid improvement of hypercholesterolemia by LDL-A in steroid-resistant NS will provide more rapid relief from NS than steroid therapy alone.

Subthreshold stimulation in three types of reentrant supraventricular tachycardia: correlation with the results of catheter ablation

The effects of subthreshold stimulation (STS) by direct current were investigated in 20 patients with atrioventricular nodal reentrant tachycardia (AVNRT), 27 with atrioventricular reentrant tachycardia (AVRT) and 3 with idiopathic atrial reentrant tachycardia (IART) STS was delivered to each eligible site for ablation prior to radiofrequency application. STS was defined as 'positive' if it could terminate the tachycardia or disrupt the conduction of accessory pathways without myocardial capture and defined as 'negative' if it could not. Radiofrequency ablation was performed irrespective of a positive or negative result from STS and was successful in all 50 patients. Among the 50 successful ablation sites, STS was positive at 26 sites (11 sites in AVNRT, 12 in AVRT and 3 in IART). STS was positive at 4 sites where ablation failed in 3 patients with AVRT and was negative at 8 sites where ablation was successful in 4 patients with AVNRT and 4 with AVRT. The positive and negative predictive value of STS for the detection of the optimal ablation site were, respectively, 100% and 74% in AVNRT, 73% and 72% in AVRT, and both 100% in IART STS-guided mapping is a specific method to predict the successful catheter ablation of reentrant supraventricular tachycardia.

Characteristics of fluvoxamine-induced nausea

We investigated the association between fluvoxamine and nausea from various viewpoints. The incidence of nausea induced by fluvoxamine was 29% (12/41). Plasma 5-hydroxyindoleacetic acid (p5-HIAA) levels after fluvoxamine administration were significantly higher in patients with nausea (6.6+/-3.4 ng/ml) than in those without nausea (3.5+/-2.7 ng/ml). On the other hand, no significant differences were found between patients with and patients without nausea in terms of sex, age, initial and maximum dosages of fluvoxamine and its plasma concentrations, and clinical response to fluvoxamine. However, the incidence of nausea in patients who were initially administered fluvoxamine at under 50 mg/day was significantly lower than in those who were started at above 50 mg/day. In addition, mosapride, a member of the benzamide family, was effective in alleviating fluvoxamine-induced nausea. These results suggest that fluvoxamine-induced nausea is associated with hyperactivity in serotonergic neurons.

Cloning and characterization of a p53-related protein kinase expressed in interleukin-2-activated cytotoxic T-cells, epithelial tumor cell lines, and the testes

A human protein kinase, p53-related protein kinase (PRPK), was cloned from an interleukin-2-activated cytotoxic T-cell subtraction library. PRPK appears to be a homologue of a growth-related yeast serine/threonine protein kinase, YGR262c. However, a complementation assay using YGR262c-disrupted yeast indicated that PRPK is not functionally identical to the yeast enzyme. PRPK expression was observed in interleukin-2-activated cytotoxic T-cells, some human epithelial tumor cell lines, and the testes. The intrinsic transcriptional activity of p53 was up-regulated by a transient transfection of PRPK to COS-7 cells. PRPK was shown to bind to p53 and to phosphorylate p53 at Ser-15. These results indicate that PRPK may play an important role in the cell cycle and cell apoptosis through phosphorylation of p53.

Possible relationship between combined plasma concentrations of risperidone plus 9-hydroxyrisperidone and extrapyramidal symptoms. Preliminary study

We investigated the relationships between extrapyramidal symptoms (EPS) induced by risperidone, the dosage of risperidone and the combined plasma concentrations of risperidone plus its active metabolite, 9-hydroxyrisperidone, in 20 schizophrenic patients. There was a positive correlation between the scores on the Simpson and Angus Scale and both the dosage of risperidone and the sum of the plasma levels of risperidone and 9-hydroxyrisperidone. These results suggest that EPS induced by risperidone increase in conjunction with both the dosage of risperidone and the total plasma concentrations of the parent compound and its active metabolite.

Association of plasma free-3-methoxy-4-hydroxyphenyl (ethylene)glycol, natural killer cell activity and delirium in postoperative patients

We measured and compared levels of plasma free 3-methoxy-4-hydroxyphenyl (ethylene)glycol (pMHPG), a major metabolite of noradrenaline, and natural killer (NK) cell activity in 26 patients prior to their undergoing an operation for cardiovascular diseases; 11 of whom expressed delirium and 15 who did not. In conclusion, we found that pMHPG levels before an operation were higher in patients with postoperative delirium than in the patients without, while NK cell activity showed no difference between the two groups. It is possible that hyperactivity of noradrenargic neurons is connected with the development of postoperative delirium. Furthermore, we considered that measurement of pMHPG level before operation might be a useful tool to predict the occurrence of postoperative delirium.

Stereoselective hydrocoupling of [(1R)-exo]-3-exo-(diphenylmethyl)bornyl cinnamates by electroreduction

[reaction: see text]. The chiral auxiliary [(1R)-exo]-3-exo-(diphenylmethyl)borneol, synthesized from (1R)-(+)-camphor in three steps, was highly effective for the stereoselective hydrocoupling of its cinnamates by electroreduction. From the resulting hydrodimers, (3R,4R)-3,4-diaryladipic acid esters and (3R,4R)-3,4-diarylhexane-1,6-diols were synthesized in 87-95% ee.

Effect of clonazepam treatment on antipsychotic drug-induced Meige syndrome and changes in plasma levels of GABA, HVA, and MHPG during treatment

We demonstrated the effect of clonazepam (2 mg/day) on Meige syndrome in two schizophrenic patients under continuous treatment with antipsychotic drugs, and changes in the plasma levels of gamma-aminobutyric acid (GABA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) in these cases. The plasma levels of HVA and MHPG during treatment with clonazepam were decreased in the responder, while not changed in the non-responder to clonazepam. A difference between the responder and the non-responder was not found in the plasma GABA levels. These results suggest that hyperactivities of the central dopaminergic and noradrenergic neurones are involved in the pathophysiology of Meige syndrome.

Purification and characterization of an acid amidase selective for N-palmitoylethanolamine, a putative endogenous anti-inflammatory substance

N-Arachidonoylethanolamine (anandamide) is cannabimimetic, and N-palmitoylethanolamine is anti-inflammatory and immunosuppressive. We found an amidase that is more active with the latter than the former in contrast to the previously known anandamide amidohydrolase for which N-palmitoylethanolamine is a poor substrate. Proteins solubilized by freezing and thawing from the 12,000 x g pellet of various rat organs hydrolyzed [(14)C]N-palmitoylethanolamine to palmitic acid and ethanolamine. The specific enzyme activity was higher in the order of lung > spleen > small intestine > thymus > cecum, and high activity was found in peritoneal and alveolar macrophages. The enzyme with a molecular mass of 31 kDa was purified from rat lung to a specific activity of 1.8 micromol/min/mg protein. Relative reactivities of the enzyme with various N-acylethanolamines (100 microm) were as follows: N-palmitoylethanolamine, 100%; N-myristoylethanolamine, 48%; N-stearoylethanolamine, 21%; N-oleoylethanolamine, 20%; N-linoleoylethanolamine, 13%; anandamide, 8%. The enzyme was the most active at pH 5 and was activated 7-fold by Triton X-100. The enzyme was almost insensitive to methyl arachidonyl fluorophosphonate, which inhibited anandamide amidohydrolase potently. Thus, the new enzyme referred to as N-palmitoylethanolamine hydrolase was clearly distinguishable from anandamide amidohydrolase.

A case of submandibular malignant rhabdoid tumor transformed from papillary thyroid carcinoma

Malignant rhabdoid tumor (MRT) in the neck region is very rare. We report a case of MRT in a 60-year-old woman who had a history of papillary carcinoma of the thyroid gland 7 years previously. One year before admission, in 1995, thyroid carcinoma recurred, and the tumor contained a small undifferentiated region with rhabdoid features. The tumor in 1996 consisted of round to oval rhabdoid cells with abundant cytoplasm, and the growth pattern was diffuse and infiltrative, with no papillary structures. We therefore concluded that the lesion was MRT, transformed from papillary thyroid carcinoma.

[Side effects and its countermeasures of antidepressant]

We reviewed the side effects of antidepressants. Tricyclic antidepressants(TCAs) are associated with a higher frequency of adverse events than those of SSRIs and SNRIs, particularly with respect to anticholinergic-like effects(dry mouth, constipation, and blurred vision), delirium, and cardiovascular adverse events. On the other hand, SSRIs have some special side effects that include nausea, sexual dysfunction, and extrapyramidal symptoms. With regard to milnacipran, a member of the SNRI family, dysuria occurs at a higher frequency than with TCAs or SSRIs. When side effects occur, clinicians give patients symptomatic treatment or substitute the drugs that cause the adverse effects with other antidepressants that have different pharmacological effects.

Entrapment of a guide wire by the Chiari network in a patient with ablated idiopathic ventricular tachycardia

Using a guide wire before insertion of a sheath is a common procedure with infrequent complications. We report an unusual case of a guide wire having been entrapped by the Chiari network prior to an intended radiofrequency ablation procedure, and which could be observed using intracardiac echocardiography. Using transthoracic echocardiography prior to ablation, this patient had been shown to have a relatively large Chiari network. We caution against using a long guide wire in patients with a large Chiari network.

[Delayed radial nerve palsy following a humeral shaft fracture]

We reported a 24-year-old man with right radial nerve palsy. He had suffered from a right humeral shaft fracture approximately three years before. The fracture was treated with intramedullary nailing. Our radiograph of the right upper limb showed callus around the fracture site. A nerve conduction study revealed conduction block of the radial nerve at the lateral side of the callus. Tinel's sign was present in the median nerve at the medial side of the callus. Surgical exploration revealed that the radial nerve trunk was compressed at the callus site. The median nerve trunk was close to the callus. We decompressed radial nerve trunk, and the patient's neurological symptoms improved gradually after the operation. Delayed radial nerve palsy has been reported only rarely, whereas acute compression of the nerve sometimes occurs after humeral shaft fractures. Morever, the median nerve also was vulnerable to compression at the site of callus. These findings underscore the importance of taking into account the possibility of delayed compression neuropathy after humeral shaft fracture.

Marked activation of the N-acylphosphatidylethanolamine-hydrolyzing phosphodiesterase by divalent cations

N-Acylethanolamines including anandamide (an endogenous ligand for cannabinoid receptors) are released from N-acylphosphatidylethanolamine (N-acyl-PE) by the catalysis of a phosphodiesterase of the phospholipase D type. The enzyme was solubilized from the particulate fractions of rat heart with the aid of octyl glucoside, and partially purified by anion-exchange chromatography. The enzyme hydrolyzed N-palmitoyl-PE with a specific activity of 17 nmol/min/mg protein at 37 degrees C. The enzyme activity increased dramatically up to 30-fold by millimolar order of Ca(2+). Ca(2+) could be replaced with other divalent cations such as Co(2+), Mg(2+), Mn(2+), Ba(2+), Sr(2+) and Ni(2+). The hydrolysis of N-arachidonoyl-PE (a precursor of anandamide) was also markedly stimulated by Ca(2+).

Precise emission probabilities of gamma-rays of 159Gd

Measurement of emission probabilities for principal gamma-rays of 159Gd with 4pibeta(ppc)-gamma(HPGe) coincidence apparatus has given precise values as indicated by uncertainties of about 1%. Improved certainties are seen when comparing the present results with emission probabilities evaluated in Nuclear Data Sheets (Helmer, 1994, p. 72) for which the uncertainties are about 24%. The improvement resulted in precise decay scheme parameters of the nuclide.

[Metastatic liver tumor arising from prostate cancer following transurethral resection of the prostate--a report of two cases]

We herein present a report of metastatic liver tumor arising from prostate cancer following transurethral resection of the prostate (TUR) in two patients. The two patients were diagnosed as having moderately differentiated prostate adenocarcinoma, either stage C or B2, and underwent hormonal and/or radiation therapy. TUR was performed due to the patients' complaints of urinary outlet obstruction. Liver metastasis, without evidence of bone or pulmonary metastasis, was then noted 23 and 5 months later in the patients with stage C and B2 prostate cancer, respectively. It is possible that the process of TUR is related to the release of tumor cells from the prostate into the systemic circulation and involved in the development of liver metastasis.

In vitro absorption and metabolism of a citrus chemopreventive agent, auraptene, and its modifying effects on xenobiotic enzyme activities in mouse livers

We previously reported that auraptene (7-geranyloxycoumarin, AUR), widely occurring in citrus fruit, is a structurally novel type of effective cancer-preventive agent, as manifested in several rodent models. However, its bio-availability and metabolism in biological systems have yet to be investigated. In the present study, we examined the chemical stability of AUR at pH 1.57 and 37 degrees C (as a stomach digestion model) and observed its stoichiometric conversion to umbelliferone [7-hydroxycoumarin, UMB; half-life (t1/2) = 15 h; 7-ethoxycoumarin (ETC) was stable for 24 h]. Differentiated Caco-2 cells, a human colorectal adenocarcinoma cell line, were used as a small intestine model. ETC permeated the basolateral (portal vein) side of Caco-2 cells in a time-dependent manner; AUR slightly permeated the cells, but with an intracellular accumulation. Epoxyauraptene and UMB were detected when AUR was treated with the rat liver S-9 mixture. ETC was also converted to UMB, but its t1/2 of two hours was much shorter than that of AUR (> 24 h). This suggests that AUR, bearing a geranyloxyl side chain, is a relatively metabolism-resistant substrate for cytochrome P-450 enzymes and, thus, is stable in the liver compared with ETC. Oral administration of AUR by gavage at 50-200 mg/kg body wt dose dependently induced glutathione S-transferase (GST) activity in mouse livers without affecting cytochrome P-450 activity. Using 10 coumarin-related compounds, we found that only those coumarins having a 7-alkyloxyl group induced GST, but not cytochrome P-450, activity. The present study presumes that AUR accumulates in the epithelial cells of the small intestine and then gradually permeates into the portal vein. Stable localizability of AUR in the colon and liver may be associated with the induction of GST activity, which is important as the action mechanism for suppression of rodent chemical carcinogenesis.

Unusual head-to-tail coupling of alkyl benzoates by electroreduction

The electroreduction of alkyl benzoates in an alcoholic solvent gave unusual head-to-tail coupled products. Usual head-to-head coupled products derived from acyloin condensation could not be detected. The best result (73% yield) was obtained from methyl benzoate using an undivided cell with an Sn cathode in i-PrOH containing tetraalkylammonium salt as a supporting electrolyte. Using an undivided cell, the products cross-coupled with a solvent molecule were obtained as byproducts. The substitution at the para position of methyl benzoate considerably decreased the yields of the head-to-tail coupled products and increased those of the cross-coupled products. The possible mechanism of the head-to-tail coupling is the attack of anion radical, generated from methyl benzoate by one-electron transfer, to another methyl benzoate. The cross-coupled products were formed by the reaction with carbonyl compound anodically produced from a solvent molecule. The cross-coupling between methyl benzoate and aromatic aldehydes was also effected by the mixed electroreduction under the same conditions.

Expression of telomerase components in oral keratinocytes and squamous cell carcinomas

Telomerase activity was measured using a telomeric repeat amplification protocol (TRAP), and expressions of the telomerase components, telomerase associated protein 1 (hTEP1), human telomerase RNA component (hTR), and human telomerase reverse transcriptase (hTERT) were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) in cultured normal oral keratinocytes and oral squamous cell carcinoma (SCC) cells. Telomerase localization was analyzed by in situ hybridization (ISH) in normal, precancerous and cancerous oral tissues. There was a strong correlation of telomerase activity with the expression levels of hTERT but not with hTEP1 or hTR mRNA in the cultured cells. Not only hTEP1 and hTR but also hTERT expression were detected in the basal cells of normal oral mucosa, and the cells expressing these mRNAs were also seen in the upper layer of leukoplakia of gingiva, and a heterogeneous pattern of expression was observed in the oral SCC tissues. These results indicate that there are at least two steps in the increase of telomerase activity during carcinogenesis in oral squamous cells; a change in distribution of cells expressing these telomerase components and the over-expression of hTERT gene in individual cells.

Dynamin is involved in human epithelial cell vacuolation caused by the Helicobacter pylori-produced cytotoxin VacA

The Helicobacter pylori-produced cytotoxin VacA induces intracellular vacuolation. To elucidate the molecular mechanism of vacuole formation by VacA, we examined the participation of dynamin, a GTPase functioning in intracellular vesicle formation, in human HeLa cells. Immunocytochemistry revealed that endogenous dynamin was localized to vacuoles induced by VacA. In cells transiently transfected with a GTPase-defective (dominant-negative) dynamin mutant, VacA failed to induce vacuolation. In contrast, VacA did induce vacuolation in cells transiently transfected with wild-type dynamin. Furthermore, under VacA treatment, neutral red dye uptake, a parameter of VacA-induced vacuolation, was inhibited in cells stably transfected with the dominant-negative dynamin mutant. In contrast, uptake was markedly enhanced in cells stably transfected with wild-type dynamin. Moreover, VacA cytopathic effects on the viability of HeLa cells were inhibited in cells stably transfected with dominant-negative dynamin-1. Sequential immunocytochemical observation confirmed that expression of dominant-negative dynamin did not affect VacA attachment to or internalization into HeLa cells. We suggest that dynamin is involved in the intracellular vacuolation induced by VacA.

Endogenous 5-HT tonically inhibits spontaneous firing activity of dorsal hippocampus CA1 pyramidal neurons through stimulation of 5-HT(1A) receptors in quiet awake rats: in vivo electrophysiological evidence

The present study was performed to examine an overall effect of endogenous serotonin (5-HT) on the spontaneous firing activity of the dorsal hippocampus CA1 pyramidal neurons in quiet awake rats. A selective 5-HT(1A) antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl)cyclohe xanecarboxamide (WAY-100635: 0.03-0.2 mg/kg, s.c.) significantly increased the firing activity. A depletion of 5-HT with parachlorophenylalanine (PCPA: 500 mg/kg/day x 3 days) completely abolished this increasing effect of WAY-100635. The baseline spike frequency of the PCPA-treated rats (3.90 +/- 0.39 Hz) was significantly higher than that of the vehicle-treated rats (2.09 +/- 0.19 Hz). A 5-HT(2A) antagonist ritanserin (1 mg/kg, i.p.) and a 5-HT(3/4) antagonist 2-methoxy-4-amino-5-chloro benzoic acid 2-(diethylamino) ethyl ester (SDZ-205557: 3 mg/kg, s.c.) did not modify the firing activity and the increasing effect of WAY-100635. These results suggest that, in quiet awake rats, endogenous 5-HT would tonically inhibit the spontaneous firing activity of the CA1 pyramidal neurons mainly through stimulating 5-HT(1A) receptors.