Oxidative stress and disturbed glutamate transport in hereditary nucleotide repair disorders

Xeroderma pigmentosum group A (XPA) and Cockayne syndrome (CS) are hereditary DNA repair disorders complicated by progressive neurodegeneration. Here we immunohistochemically examine the in situ expression of materials that are produced by oxidative stress and glutamate transporters (which can contribute to prevention of glutamate neurotoxicity) in the brains of 5 autopsied patients each of XPA, CS, and control groups. All oxidative products, including nitrotyrosine, advanced glycation end product, and 4-hydroxy-2-nonenal-modified protein (HNE) were deposited in large amounts in the globus pallidus of CS patients compared to XPA patients. They were frequently recognized in the pseudocalcified foci and free minerals in the neuropil, and more rarely in foamy spheroids. In addition, the deposition of HNE was observed also in hippocampal and cerebellar dentate neurons of both CS and XPA patients. The expression of glial glutamate transporters, EAAT1 and GLT-1, was affected in the globus pallidus in 5 CS patients and 3 XPA patients. They were also altered in the cerebellar cortex in most of the CS patients. These data suggest that oxidative stress and disturbed glutamate transport may be involved in pallidal and/or cerebellar degeneration in hereditary nucleotide repair disorders.

One missense mutation in the factor X gene causing factor X deficiency--factor X Kanazawa

We investigated the molecular basis of factor X deficiency in a Japanese patient whose factor X activity and antigen level were 45% and 50% of normal control values, respectively. All exons and intron/exon junctions of the factor X gene were studied using a strategy combining polymerase chain reaction (PCR) amplification and nonradioactive single-strand conformational polymorphism (SSCP) analysis. Exon 5, containing the DNA fragment of the proband, showed aberrant migration by SSCP analysis. All exon-containing DNA fragments amplified by PCR were sequenced, and it was revealed that the proband was a heterozygote for a G --> A substitution in exon 5 of the factor X gene of the proband. This mutation predicts an amino acid replacement of arginine (Arg) for glycine (Gly) at codon 114 in the second EGF-like domain.

[Pulmonary edema in a child following laryngospasm triggered by a laryngeal mask airway during emergence from anesthesia]

A 9-year-old boy underwent biopsy of the tumor at the external auditory meatus under general anesthesia with a laryngeal mask airway(LMA). During emergence from anesthesia, laryngospasm with marked inspiratory effort and cyanosis occurred. The LMA was removed and the patient was orotracheally intubated following vecuronium administration. In spite of controlled ventilation with 100% oxygen, oxygen saturation remained at low 90s and pink frothy sputum appeared in the tracheal tube. We suspected negative pressure pulmonary edema and treated him with mechanical ventilation with positive end-expiratory pressure. Seventeen hours later the pink frothy sputum decreased and he was extubated. Laryngospasm during emergence from anesthesia with an LMA can induce negative pressure pulmonary edema, especially in pediatric patients.

Resection of liver metastasis after a pancreatoduodenectomy for pancreatic cancer: a case report

A case of resected liver metastasis from pancreatic cancer, in a 69-year-old woman who obtained a relatively long survival, is presented. Primary pancreatic cancer was found in a patient presenting with obstructive jaundice and a loss of appetite. A pylorus-preserving pancreatoduodenectomy was carried out on December 2, 1996. Eleven months later, a 1.5-cm mass was found in the right posterior segment of the liver. Although the tumor size had increased to 2.5 cm 5 months later, no other metastases were observed. Therefore, the right posterior segment of the liver was resected. Eleven months after the second operation, recurrence was found in the cut surface of the liver and the left caudate lobe. She died on May 1, 1999. This case demonstrated a relatively favorable prognosis in comparison to other common type of liver metastasis from pancreatic cancer. This study discusses the peculiarities of this case and emphasizes the necessity to carefully select the patients before attempting to resect the liver metastasis from pancreatic cancer.

Characterization of monoclonal antibodies against Hokkaido strain tick-borne encephalitis virus

A tick-borne encephalitis (TBE) patient was found in Hokkaido in 1993, and TBE viruses were isolated from animals and ticks in our previous studies. To develop a diagnostic reagent to identify TBE viruses, monoclonal antibodies (Mabs) were produced against the TBE virus strain Hokkaido (Oshima 5-10). Seven Mabs were obtained which reacted with the envelope protein of the Oshima 5-10 strain. These Mabs were flavivirus genus-specific, TBE virus complex-specific or TBE virus type-specific. The Mabs are applicable for identification of TBE virus strains.

Detection of hantaviral antibodies among patients with hepatitis of unknown etiology in Japan

Hantaviral antibodies were detected in the sera from patients with hepatic disease of unknown etiology in Japan by several different serological diagnostic methods. A total of 105 sera from diseased patients which were negative to A-G hepatitis virus infections in the Tokyo area were tested. Among them, 3 out of 73 sera from patients with chronic hepatic disease were positive to hantaviral antibody by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescent antibody assay (IFA) and Western blot analysis (WB). Neutralizing antibody titers of the 3 sera to Seoul virus (SEO) were 4 to 8 times higher than those to Hantaan virus (HTN). However, all of the 32 sera from patients with acute hepatitis were negative for hantaviral antibody. Among the 60 patients with chronic hepatitis in Hokkaido which were serologically negative to B and C hepatitis virus infection, one was positive for hantaviral antibody by ELISA and WB. In contrast, the sera from healthy adults in Japan, 550 from the Honshu and Kyushu regions, and 1,000 from the Hokkaido region, were negative for hantavirus antibody. These results show that hantaviral antibodies are more frequently detected in patients with hepatic disease than in healthy adults. However, the observation that no positive sera were detected from patients with acute hepatitis implies that hantavirus might not be directly related to hepatitis.

The mechanism of actinomycin D-mediated increase of Borna disease virus (BDV) RNA in cells persistently infected by BDV

The transcriptional mechanism of Borna disease virus (BDV) has been poorly understood. We have analyzed transcription of the virus upon various stimuli in Madin-Darby canine kidney cells which were persistently infected by BDV (MDCK/BDV). Treatment with actinomycin D (ActD) increased the level of BDV RNA, shifting the size of RNA from 1.9 kb to 2.3 kb beginning 5 hr after the treatment. To understand the mechanism of this unique modulation of BDV RNA, we conducted several experiments. The RNA increase occurred at the stage in which synthesis of cellular intrinsic mRNA was intact, suggesting BDV does not compete with cellular transcriptional machinery for intrinsic RNA polymerase II. The BDV transcription was also enhanced by cycloheximide treatment, indicating that newly synthesized viral or cellular proteins are not necessary for viral transcription. However, a shift in the RNA size was not observed for cycloheximide-induced BDV RNA. The increase in viral transcription persisted during the cellular apoptotic process consequent to p53 gene accumulation beginning 1 hr after ActD treatment. Caspase inhibitors Z-VAD and DEVD-CHO repressed the apoptotic process but failed to block the increase in BDV transcription. In addition, adenovirus-mediated transduction of wild-type p53 did not alter the BDV transcription, indicating that the increase in BDV transcription was independent of the p53-mediated apoptotic process. Other various stimuli that evoke cellular signal transductions failed to alter BDV transcription. Agents inhibitory to topoisomerase except adriamycin failed to enhance BDV transcription, indicating that the increase in BDV transcription is not mediated by an inhibitory action to the topoisomerase II of ActD. Adriamycin showed an increase and size-shift of BDV RNA similar to ActD. These results suggest that intercalation of the viral genome itself with ActD is related to the stabilization of viral RNA and alteration of RNA size rather than secondary host cell changes.

'Iatrogenic' Wernicke's encephalopathy in Japan

'Iatrogenic' Wernicke's encephalopathy has appeared to occur more frequently in Japan, probably induced by the change of our Japanese national health insurance policy in 1992. We report 4 nonalcoholic patients with such Wernicke's encephalopathy, which occurred during the early postoperative oral food intake period following intravenous nutrition without vitamin supplements. We analyzed the medical records of 4 patients, 3 men and 1 woman, aged between 55 and 71 years, who were admitted to our hospital between 1992 and 1995. Three patients underwent gastrointestinal surgery and 1 suffered chronic pyothorax. We diagnosed our patients as having Wernicke's encephalopathy based on typical neurological abnormalities, in addition to typical cranial magnetic resonance image findings, low serum vitamin B(1) levels, or both. Although all of the patients were treated with vitamin B(1) and showed some improvement, 1 patient developed Korsakoff syndrome, 2 made incomplete neurological recovery, and 1 died. We speculated that the body vitamin B(1) stores had been decreasing in our patients who did not receive any vitamin supplements during intravenous hyperalimentation or hydration. Subsequent administration of high calorie and high carbohydrate oral diets increased the demand for vitamin B(1), further depleting the vitamin stores, thereby causing 'iatrogenic' Wernicke's encephalopathy. The change of our national health insurance policy in 1992 discouraged the routine administration of vitamins, probably causing Wernicke's encephalopathy in our patients.

[A point mutation at Arg169 (CGG-->TGG) in hereditary protein C deficiency]

We investigated a 56-year-old Japanese man with protein C deficiency, who was referred to our hospital because of venous sinus thrombosis and pulmonary thromboembolism. Protein C (PC) activity and the corresponding antigen level in plasma were 66% and 106% of the normal values, respectively. Both the activity and antigen levels of protein C were reduced by approximately 50% in plasma from the patient's mother. All exons and their flanking intron regions were amplified by PCR from genomic DNA. Sequencing analysis of the PCR fragments revealed that the patient was heterozygous for a C to T substitution at nucleotide position 6218, resulting in a single amino acid substitution of arginine (CGG) by tryptophan (TGG) at codon 169 of the heavy chain. We analyzed the patient, his mother, and normal controls by a Sac II digestion study of exon 7 and found that the patient and his mother had the same C to T point mutation at base 6218. This mutation could have been responsible for the defective activation of the molecule and the resulting thrombotic disorder. The patient is now being treated with warfarin, and so far no further clinical thrombotic episode has occurred.

Epidemiology of tick-borne encephalitis (TBE) and phylogenetic analysis of TBE viruses in Japan and Far Eastern Russia

In Oshima, the southern part of Hokkaido, a tick-borne encephalitis (TBE) patient was found in 1993; in addition TBE virus was isolated from the blood samples of sentinel dogs, ticks pools, and rodents spleens in 1995 and 1996 by suckling mice. To identify when these TBE viruses emerged in Hokkaido, the times of divergence of TBE virus strains isolated in Oshima and Far Eastern Russia were estimated. TBE virus was isolated in Khabarovsk in 1998, and the nucleotide sequences of viral envelope protein genes of isolates from Oshima and Khabarovsk were compared. Based on the synonymous substitution rates of these virus E-protein genes, the lineage-divergence times of these TBE virus strains were predicted phylogenetically to be approximately 260-430 years ago. Furthermore, the virulence of TBE virus isolates from Oshima and Khabarovsk were compared in a mouse model. The results showed that the isolates possessed very similar virulence in mice. European TBE vaccine was found to be effective in TBE virus, Hokkaido strain. This review provides evidence that the Oshima strains of TBE virus in Hokkaido emerged from the Far Eastern Russia a few hundred years ago, which explains why the virulence of these strains is similar to that of TBE viruses isolated in Russia. Practical application of the vaccine should be considered in Japan.

Identification of SWI.SNF complex subunit BAF60a as a determinant of the transactivation potential of Fos/Jun dimers

Fos family proteins form stable heterodimers with Jun family proteins, and each heterodimer shows distinctive transactivating potential for regulating cellular growth, differentiation, and development via AP-1 binding sites. However, the molecular mechanism underlying dimer specificity and the molecules that facilitate transactivation remain undefined. Here, we show that BAF60a, a subunit of the SWI.SNF chromatin remodeling complex, is a determinant of the transactivation potential of Fos/Jun dimers. BAF60a binds to a specific subset of Fos/Jun heterodimers using two different interfaces for c-Fos and c-Jun, respectively. Only when the functional SWI.SNF complex is present, can c-Fos/c-Jun (high affinity to BAF60a) but not Fra-2/JunD (no affinity to BAF60a) induce the endogenous AP-1-regulated genes such as collagenase and c-met. These results indicate that a specific subset of Fos/Jun dimers recruits SWI.SNF complex via BAF60a to initiate transcription.

Spinal cord lesions of myelitis with hyperIgEemia and mite antigen specific IgE (atopic myelitis) manifest eosinophilic inflammation

We report the neuropathological findings of spinal cord specimens obtained from two patients who had localized myelitis with hyperIgEemia and mite antigen specific IgE (atopic myelitis). Both cases showed mild spinal cord dysfunction, and the gadolinium-enhanced area of the isolated spinal cord lesion observed on MRI was biopsied, respectively. Neuropathologically, both cases showed many perivascular lymphocyte cuffings associated with disrupted vessels, and the infiltration of eosinophils in the spinal cord lesions. Both myelin and axons were lost in the lesions, which were associated with astrogliosis. These findings suggest that an allergic mechanism may play a role in this condition.

Elevated plasma levels of free-form of TFPI antigen in hypercholesterolemic patients

Several studies have previously reported high levels of total tissue factor pathway inhibitor (TFPI) antigen in patients with hypercholesterolemia. The relationship between serum lipid concentrations and total and free-form TFPI antigen in 32 patients with primary type II hypercholesterolemia and 38 age- and gender-matched normolipemic control subjects was studied (Study Group I). Plasma concentrations of total TFPI (tTFPI) antigen, free-form TFPI (fTFPI) antigen, tissue factor antigen, factor VII activity (FVIIc), and prothrombin fragment 1+2 (F1+2) were measured. The median levels of tTFPI, fTFPI, FVIIc, and F1+2 were higher in hyperlipidemic patients compared with those in healthy subjects. The effect of lowering total cholesterol on hypercoagulability in 25 patients with type II hyperlipoproteinemia (Study Group II) were also studied. The median levels of tTFPI, FVIIc, and F1+2 decreased significantly after 6 months of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor therapy in the hypercholesterolemic patients. On the other hand, fTFPI did not change after therapy. Plasma tTFPI was strongly correlated with total cholesterol and low density lipoprotein (LDL)-cholesterol in hyperlipidemic patients. In contrast to the strong correlation between tTFPI and total cholesterol, the correlation between plasma fTFPI and total cholesterol was relatively poor. These results suggest that the activation of the anticoagulant system as well as the activation of the coagulation system may occur in association with hypercholesterolemia. Furthermore, the results of this study may suggest that lowering of total cholesterol in hyperlipidemic patients reduces the thrombin generation in plasma and that down-regulation of LDL does not affect the anticoagulant potency of TFPI in plasma.

A model for Sec incorporation with the regions upstream of the UGA Sec codon to play a key role

For eukaryotic selenoprotein mRNAs, it has been proposed that the SECIS element in the 3'-UTR is required for recognition of UGA as a Sec codon. Some proteins which bind to SECIS (SBP) have been reported. However, it is not clear how the SECIS element in the 3'-UTR can mediate Sec insertion far at the in-frame UGA Sec codons. The idea that there must be a signal near the UGA Sec codon is still being considered. Therefore, we searched for a protein which binds to an RNA sequence surrounding the UGA Sec codon on human GPx mRNA. We found a protein, prepared from bovine brain microsomes, which strongly bound to the RNA fragment upstream of the UGA Sec codon but not to the RNA sequence downstream of the UGA codon. This protein also bound to the SECIS sequence in the 3'-UTR of human GPx, and this binding to SECIS was competed with the RNA fragment upstream of the UGA Sec codon. We also obtained the similar results with the RNA fragments of type I iodothyronine 5'-deiodinase (5'DI) mRNAs. Comparison of such RNA fragments with SECIS fragments revealed similarities in the region upstream of the in-frame UGA Sec codon of several Se-protein mRNAs. The study thus favors a novel model of Sec incorporation at the UGA Sec codon that involves the regions upstream of the UGA codon of mRNAs of mammalian selenoproteins. This model explains that the stem-loop structure covering the UGA codon is recognized by SBP and how the UGA Sec codon escapes from attack by eRF.

Elevated levels of free tissue factor pathway inhibitor antigen in cases of disseminated intravascular coagulation caused by various underlying diseases

Tissue factor pathway inhibitor (TFPI) is primarily synthesized by vascular endothelial cells and is found in vivo in association with endothelial cells, lipoproteins, or in free form. Free TFPI is the most potent and important type, because it is released from endothelial cells following an injection of heparin, or as a result of pathological stimuli. In order to study the role of TFPI in disease, the concentration of free form TFPI was measured in the plasma of 114 patients suffering from disseminated intravascular coagulation (DIC), as the result of several underlying diseases. Plasma antigen levels of free TFPI were significantly higher even in those patients not exhibiting DIC than in normal healthy subjects. These levels were even higher among patients exhibiting DIC, especially those with acute promyelocytic leukemia or cancer, receiving continuous heparin drip infusions. A significant correlation was observed between the plasma antigen levels of free form TFPI and those of fibrin/fibrinogen degradation products, and free form TFPI and plasmin inhibitor complex (r = 0.428, P < 0.0001 and r = 0.329, P < 0.0001, respectively) among 114 DIC patients. There were no significant differences between the plasma levels of free TFPI in DIC patients with or without multiple organ failure. It has been suggested that the plasma levels of free TFPI are closely related to the levels of fibrinolysis occurring in DIC patients, although further study is required to clarify the degree to which TFPI is expressed by endothelial cells during DIC.

Effects of a thromboxane receptor antagonist (NT-126) and a thromboxane synthase inhibitor (OKY-O46) on protamine-induced circulatory changes in dogs

OBJECTIVE

To examine whether a thromboxane receptor antagonist, NT-126, or a thromboxane synthase inhibitor, OKY-046, prevents circulatory changes caused by protamine reversal of heparin and to evaluate the significance of thromboxane generation in the phenomena.

DESIGN

Prospective, randomized, controlled, animal study.

SETTING

A university research laboratory.

PARTICIPANTS

Twenty-four adult mongrel dogs.

INTERVENTIONS

According to the pretreatments, the animals were divided into 3 groups (n = 8 in each): (1) control (normal saline); (2) NT-126, 0.01 mg/kg; and (3) OKY-046, 1 mg/kg. Under general anesthesia, all animals were anticoagulated with intravenous heparin, 200 IU/kg, 5 minutes before the pretreatment. Five minutes after the pretreatment, protamine sulfate, 2 mg/kg, was administered intravenously over 10 seconds. Hemodynamic variables were recorded repeatedly until 60 minutes after the protamine. Plasma thromboxane B2 level was determined at baseline and 10 minutes after protamine injection.

MEASUREMENTS AND MAIN RESULTS

The average values of mean arterial blood pressure and mean pulmonary artery pressure among the 3 groups in each period and values in each group over the study period were not significantly different. There was weak correlation between maximum percent increases in systolic pulmonary artery pressure or maximum percent decreases in systolic arterial blood pressure for 5 minutes after the protamine versus percent increases in plasma thromboxane B2 level.

CONCLUSION

Neither NT-126 nor OKY-046 appears to be effective in preventing protamine-induced circulatory changes in this dog model, suggesting that thromboxane generation alone is not responsible for the phenomena.

[Intracellular calcium kinetics after odorant stimulus in olfactory receptor cells isolated from mice]

cAMP and IP3 act as secondary messengers in olfactory signal transduction and when activated, stimulate calcium levels in olfactory receptor cells. Little is known however, about the causal mechanism. We studied calcium kinetics in mouse olfactory receptor cells after odorant stimuli. Olfactory receptor cells were isolated from female BALB/c mice, treted with trypsin, and stained with Fura-2/AM. Changes in intracellular Ca2+ concentrations in stained cells were measured with a fluorescent microscopic image-processing device (ARGUS-50; Hamamatsu Photonix, Japan). We found that intracellular Ca2+ concentrations rose after exposure to a set of odorants, including 3-ethoxy-4-hydroxy-benzaldehyde, caprylic acid, heptanoic acid, nonanoic acid, eugenol, phenethyl alcohol, and n-amyl acetate. Adding 2', 5'-dideoxyadenosine, a cAMP inhibitor, beforehand suppressed olfactory receptor cell response to odorants. Intracellular Ca2+ concentrations increased substantially in response to stimulation by odorants in calcium-free Ringer's solution, but only a slight increase was seen in intracellular calcium concentration in response stimulation by a high concentration of K+ (145.6 mM) in calcium-free Ringer's solution. The increase in intracellular Ca2+ concentration after odorant stimuli was suppressed when olfactory receptor cells were pretreated with ryanodine, which releases Ca2+ from intracellular stores. These findings suggest that elevated Ca2+ concentrations may be involved in releasing Ca2+ from intracellular calcium stores in mouse olfactory receptor cells, in which cAMP functions as a secondary messenger in olfactory signal transduction.

Endogenous AP-1 levels necessary for oncogenic activity are higher than those sufficient to support normal growth

We investigated the role of endogenous AP-1 in human tumor cell lines by introducing SupJunD-1, a dominant-negative mutant of AP-1, using vesicular stomatitis virus G protein (VSV-G)-pseudotyped retrovirus vectors. Single inoculation of six human tumor cell lines, originating from osteosarcomas, non-small cell lung carcinomas or cervical carcinomas, with recombinant SupJunD-1 virus at a high multiplicity of infection readily inhibited colony formation in soft agar. We detected no significant changes in expression levels of AP-1 components c-Jun or Fra-1, adhesion molecules CD44 or E-cadherin, or cell cycle regulator p53, which are encoded by genes previously reported to be under the control of AP-1 in some mouse or human cell lines. By varying the dosage of VSV-G-pseudotyped retrovirus, we were able to change the proviral copy number of supjunD-1 from 1 to approximately 10 and monitor suppression of endogenous AP-1 function as assessed by growth characteristics of the tumor cell lines, we found a SupJunD-1 dosage which significantly suppressed anchorage-independent growth without affecting the cellular growth in monolayer cultures at all. We conclude that endogenous AP-1 levels necessary for oncogenic activity are much higher than those sufficient to support normal growth.

Arterial dissections of penetrating cerebral arteries causing hypertension-induced cerebral hemorrhage

OBJECT

For the past 130 years, it has been believed that hypertension-induced cerebral hemorrhages are the result of ruptures of microaneurysms or ruptures of arteries that have degenerative changes. The majority of previous investigations have focused on autopsied brain. In this study, the authors attempted to verify the cause of hypertension-induced cerebral hemorrhage by using surgical specimens of the penetrating arteries responsible for the hemorrhages.

METHODS

Between 1997 and 1999, the authors performed pathological studies in surgical specimens of lenticulostriate arteries that had been confirmed during microsurgery to be the cause of hypertension-induced hemorrhage of the putamen. Nineteen lenticulostriate arteries were collected from 12 patients. Fifteen of these arteries were verified as the pathological causes of hemorrhage. They included six arterial dissections, six arterial ruptures with substantial degenerative changes, and three arterial ruptures with few degenerative changes. The pathological findings in the lenticulostriate artery dissections were similar to those of typical arterial dissections in major cerebral arteries.

CONCLUSIONS

To the best of the authors' knowledge, arterial dissections of lenticulostriate arteries have not been identified as a cause of hypertension-induced cerebral hemorrhages. When penetrating arteries are included as causative vessels, cerebral arterial dissections may be much more common than previously thought.

mRNA expression of type I and type II receptors for activin, transforming growth factor-beta, and bone morphogenetic protein in the murine erythroleukemic cell line, F5-5.fl

OBJECTIVE

Intracellular signaling of activin and transforming growth factor-beta (TGF-beta) is thought to be mediated by the same molecules (Smad2/3 and Smad4). Although differentiation of murine erythroleukemia F5-5.fl cells is induced by activin, it is not induced by TGF-beta, suggesting that at some point TGF-beta signaling is defective. The aim of this study was to investigate the unresponsiveness of F5-5.fl cells to TGF-beta.

DESIGN

mRNA expression of ligands, receptors, and signal mediators for the TGF-beta family was examined in F5-5.fl cells using RT-PCR.

RESULTS

Activin induced erythrodifferentiation of F5-5.fl cells in a dose-dependent manner. Neither TGF-beta1 nor bone morphogenetic protein (BMP)-4 affected the differentiation of F5-5.fl cells in the presence or absence of activin. Although mRNAs of TGF-betas (TGF-beta1, TGF-beta2 and TGF-beta3) were detected, those of inhibin/activin (alpha-, betaA- and betaB-subunits) and BMPs (BMP-2, BMP-4 and BMP-7) could not be detected in the cells, suggesting that neither activins nor BMPs are produced in F5-5.fl cells. The expression of both type I (ALK-4/ActRIB) and type II (ActRII) receptors for activin was detected in F5-5.fl cells. In contrast, while the expression of type I receptor for TGF-beta (ALK-5/TbetaRI) was detected, that of type II receptor (TbetaRII) was not. The mRNA of all Smads examined was detected in F5-5.fl cells.

CONCLUSIONS

A defect in the type II receptor might cause unresponsiveness to TGF-beta in F5-5.fl cells. An erythrodifferentiation assay using F5-5.fl cells would be useful for measuring net activin activity because it would not be necessary to consider endogenous activins and BMPs.

In vitro antiviral activity of lactoferrin and ribavirin upon hantavirus

Bovine lactoferrin (LF) and ribavirin (Rbv) were tested as antiviral agents against Seoul type hantavirus (SR-11 strain) in vitro. Hantaviral foci number in Vero E6 cells infected with SR-11 was reduced with LF treatment by 5 days post infection to obtain a 50% effective dose (ED50) of 2500 microg/ml, while pretreatment with LF was highly efficacious having an ED50 of 39 microg/ml. Conversely, 1 h pretreatment with Rbv revealed no inhibition of viral focus formation but could significantly reduce the number of viral foci (ED50: 10 microg/ml) when used from the time of viral infection. One hour pre-treatment of the cell monolayer with LF and subsequent addition of Rbv revealed a synergistic anti-hantaviral effect against SR-11, <20 FFU/ml as compared to 10(5) foci/ml in the control. One hour treatment of SR-11 with LF prior to cell inoculation gave an ED50 of 312.5 microg/ml. Whereas, washing the LF-pretreated cell monolayer with PBS demonstrated minimal focus reduction, suggesting LF lightly adheres to cells. These results indicate that LF has anti-hantaviral activity in vitro and inhibition of virus adsorption to cells which play an important role in revealing the anti-hantaviral activity of LF. This paper reports for the first time the anti-hantaviral effect of LF.

Muscular dystrophy: centronucleation may reflect a compensatory activation of defective myonuclei

Muscular dystrophy has long been believed to be characterized by degeneration and abortive regeneration of muscle fibers (the muscle degeneration theory), but unfortunately its pathogenesis is still unclear and an effective treatment has yet to be developed. As a challenge to the theory, we have proposed an alternative muscle-defective-growth theory and a further bone muscle growth imbalance hypothesis supposing possible defects in bone-growth-dependent muscle growth based on our findings in hereditary dystrophic dy mice (C57BL/6J dy/dy). This review presents some new insights into the pathogenesis of the disease along with our hypothesis, focusing on the physiological meaning of centronucleation, one of the major pathological changes commonly observed in dystrophic muscles of man and experimental animals.

[Diagnostic criteria of diffuse Lewy body disease]

DLBD is also called Dementia with Lewy bodies(DLB) which was proposed by the consortium on DLB international workshop(CDLB) in 1995. CDLB criteria of clinical diagnosis contain progressive cognitive decline as a mandatory feature, and fluctuating cognition, recurrent visual hallucinations and parkinsonism as 3 core features. Supportive features include repeated falls, syncope, transient loss of consciousness, neuroleptic sensitivity, and systematized delusions. CDLB pathologic criteria include the presence of Lewy bodies as the only essential feature, and associated features included Lewy-related neurites, senile plaques, neurofibrillary tangles, and regional neuronal loss in the areas vulnerable to Parkinson's disease. Lewy bodies are counted and scored from 0 to 2 in 5 designated cortical areas. Total Lewy body score of 7-10 indicates DLBD.

Nascent synthesis of leader sequence-containing subgenomic mRNAs in coronavirus genome-length replicative intermediate RNA

Infection with coronavirus results in the accumulation of genomic-sized mRNA and six to eight subgenomic mRNAs that make up a 3' coterminal nested-set structure. Genome-length negative-strand RNA and subgenomic-length negative-strand RNAs, each of which corresponds to each of the subgenomic mRNAs, also accumulate in infected cells. The present study examined whether the genome-length negative-strand RNA serves as a template for subgenomic mRNA synthesis. Genome-length replicative intermediate (RI) RNA was purified by two-dimensional gel electrophoresis of intracellular RNAs from cells infected with mouse hepatitis virus. RNase A treatment of the purified genome-length RI resulted in the production of the genome-length replicative form RNA, indicating that the genome-length RI included genome-length template RNA. RNase protection assays using the purified genome-length RI and two probes, which corresponded to the 5' 300-nt region of mRNA 6 and to the same region of mRNA 7, showed the presence of nascent leader sequence-containing subgenomic mRNAs in the genome-length RI. These data demonstrated that the genome-length negative-strand RNA serves as a template for subgenomic mRNA synthesis.

Molecular recognition of amines and amino esters by zinc porphyrin receptors: binding mechanisms and solvent effects

Zinc porphyrin receptors bearing 12 ester groups in the meso phenyl groups (1-3) were prepared, and binding of amines and alpha-amino esters was studied with emphasis on the binding mechanisms. The X-ray crystallographic analysis of 5,10,15,20-tetrakis(2, 6-bis(carbomethoxymethoxy)-4-carbomethoxyphenyl)porphyrin (free base of 1) showed that the receptor has a binding pocket above the porphyrin plane. UV-visible titration experiments revealed that the zinc porphyrin receptors bound amines and alpha-amino esters with binding constants (K(a)) ranging from 0.5 to 52 700 M(-1) in CH(2)Cl(2) at 25 degrees C. The ester functional groups of 1 assisted the binding of aromatic alpha-amino esters (K(a) = 8 000-23 000 M(-1) in CH(2)Cl(2) at 25 degrees C) and inhibited the binding of bulky aliphatic alpha-amino esters (K(a) = 460 M(-1) for Leu-OMe in CH(2)Cl(2) at 25 degrees C), indicating that CH-pi type interactions and steric repulsions control the selectivity. The binding of amines and alpha-amino esters was tight both in a nonpolar solvent (CH(2)Cl(2)) and in a polar solvent (water) but loose in a solvent of intermediate polarity (H(2)O-MeOH (1:1)), demonstrating that two competitive driving forces are operating: (1) attractive electrostatic forces between host and guest such as coordination of the amino group to the zinc atom, and (2) entropic forces stemming from desolvation as well as enthalpic forces due to the host-guest dispersion forces. The former forces drive the binding in CH(2)Cl(2) while the latter forces drive the binding in water. The enthalpy changes in the binding in CH(2)Cl(2) and those in water range from -50 to -30 kJ mol(-1) and from -35 to 0 kJ mol(-1), respectively. The entropy changes in CH(2)Cl(2) and those in water range from -120 to -60 J K(-1) mol(-1) and from -50 to +60 J K(-1) mol(-1), respectively. Thus the binding in CH(2)Cl(2) is characterized by large negative enthalpy changes, while that in water by less negative entropy changes. These thermodynamic parameters also indicate that host-guest polar interactions (enthalpic forces) drive the binding in CH(2)Cl(2) while both host-guest dispersion interactions (an enthalpic force) and desolvation (an entropic force) drive the binding in water. Enthalpy-entropy compensation observed for the binding in water indicates that the binding of amines and amino esters in water by zinc porphyrins is associated with conformational changes as well as a high degree of dehydration. In CH(2)Cl(2), no clear compensation was observed, consistent with the mechanism that neither desolvation processes nor conformational changes contribute significantly to the binding energetics.

Activin A stimulates type IV collagenase (matrix metalloproteinase-2) production in mouse peritoneal macrophages

The role of activin, a dimer of inhibin beta subunit, in mouse peritoneal macrophages was evaluated. Activin activity in the cultured macrophages was augmented in response to activation by LPS. In Western blot analysis, immunoreactive activin A was detected in the culture medium only when the macrophages were stimulated by LPS. Although mRNA expression of betaA subunit was detected, that of alpha and betaB subunit was not found in macrophages by reverse RT-PCR. The activin betaA mRNA level was increased in macrophages by LPS, suggesting that the activin production augmented by LPS is regulated at the mRNA level of the betaA gene. The mRNAs of four activin receptors (ActRI, ActRIB, ActRII, and ActRIIB) were also detected in the peritoneal macrophages, and the mRNA levels, except for ActRIB, were decreased during the LPS treatment. Exogenous activin A stimulated the mRNA expression and gelatinolytic activity of matrix metalloproteinase-2 (MMP-2) in macrophages in both the presence and the absence of LPS. In contrast, activin did not affect the production of MMP-9 in macrophages. These results suggested that 1) mouse peritoneal macrophages produced activin A; 2) expression of activin A was enhanced with activation of the macrophages; 3) the macrophages also expressed activin receptors; and 4) exogenous activin A stimulated MMP-2 expression and activity, implicating activin A as an positive regulator of MMP-2 expression. Considering that MMP-2 constitutes the rate-limiting proteinase governing the degradation of basement membrane collagens, activin A may be involved in migration and infiltration of macrophages through the basement membrane in an inflammatory state.

Expression of steroidogenic acute regulatory protein (StAR) in rat granulosa cells

Steroidogenic acute regulatory protein (StAR) is a vital mitochondrial protein that is indispensable for the synthesis of steroids. To study the mechanisms of regulation of StAR in rat granulosa cells, we used granulosa cells obtained from diethylstilbestrol-treated immature rats. Northern blot analysis revealed two major transcripts of about 3.6 kb and 1.6 kb of rat StAR mRNA. Rat StAR mRNA had strongly increased within 2 h due to the treatment of FSH or 8-Br-cAMP in this culture, a parallel increase of transcripts of both sizes was observed. Compared to the control, StAR mRNA levels increased in a dose-dependent manner in the presence of increasing concentrations of FSH (1-100 ng/ ml) and 8-Br-cAMP (0.25-5 mM). Although co-treatment of rat granulosa cells with FSH and TGF-beta did not change FSH-induced StAR mRNA levels, these levels in granulosa cells were markedly increased by pretreatment with TGF-beta before being acutely (2 h) stimulated with an effective dose of FSH. The stimulatory effect of TGF-beta was time- and concentration-dependent (1-30 ng/ml).

Characterization of mSelB, a novel mammalian elongation factor for selenoprotein translation

Decoding of UGA selenocysteine codons in eubacteria is mediated by the specialized elongation factor SelB, which conveys the charged tRNA(Sec) to the A site of the ribosome, through binding to the SECIS mRNA hairpin. In an attempt to isolate the eukaryotic homolog of SelB, a database search in this work identified a mouse expressed sequence tag containing the complete cDNA encoding a novel protein of 583 amino acids, which we called mSelB. Several lines of evidence enabled us to establish that mSelB is the bona fide mammalian elongation factor for selenoprotein translation: it binds GTP, recognizes the Sec-tRNA(Sec) in vitro and in vivo, and is required for efficient selenoprotein translation in vivo. In contrast to the eubacterial SelB, the recombinant mSelB alone is unable to bind specifically the eukaryotic SECIS RNA hairpin. However, complementation with HeLa cell extracts led to the formation of a SECIS-dependent complex containing mSelB and at least another factor. Therefore, the role carried out by a single elongation factor in eubacterial selenoprotein translation is devoted to two or more specialized proteins in eukaryotes.

Slowly progressive heart failure due to subepicardial myocardial fibrosis in a patient with chronic pericardial effusion

A 65-year-old woman was admitted to hospital because of orthopnea. She had been followed-up for chronic pericardial effusion detected by echocardiography 10 years previously. Initial echocardiography showed that the left ventricular diastolic diameter (LVDd) was 39 mm and percent fractional shortening (%FS) was 33.3%. Neither fluid samples nor a pericardial biopsy specimen identified the etiology. Cardiac tamponade was not evident, and C-reactive protein and creatine-kinase values were within normal limits. During follow-up, the %FS decreased gradually, but the LVDd remained unchanged. On admission, echocardiography showed that the %FS was 12.5% and LVDd was 40 mm. She developed intractable hyponatremic heart failure with bilateral pleural effusion. Autopsy findings revealed that infiltration of small lymphocytes in the epicardium had penetrated into the subepicardial myocardium. The subepicardial myocardium and the interventricular septal myocardium were diffusely replaced by fibrosis, which could have induced restrictive diastolic heart failure and reduced left ventricular contractility. The fibrosis was not detected in the epicardium itself nor the subendocardial myocardium. This is the first report describing diffuse subepicardial myocardial fibrosis in a patient with chronic pericardial effusion and progressive heart failure.

NACP/alpha-synuclein and tau constitute two distinctive subsets of filaments in the same neuronal inclusions in brains from a family of parkinsonism and dementia with Lewy bodies: double-immunolabeling fluorescence and electron microscopic studies

The co-localization of NACP/alpha-synuclein and tau epitopes was examined in the brain stem and hippocampal formation in two patients from a family of autosomal dominant parkinsonism and dementia with Lewy bodies (LBs) without two reported missense mutations in the NACP gene. Double-labeling immunofluorescence study revealed that some brain stem LBs, cortical LBs, pale bodies, Lewy-related neurites, and neurofibrillary tangles expressed both NACP epitopes and the PHF tau AT8 epitope. Double-immunolabeling electron microscopy demonstrated that the NACP antibody selectively labeled 9- to 13-nm-thick straight filaments (LB filaments), whereas AT8 recognized twisted tubules with 80-to 100-nm-interval constrictions in the same neuronal inclusions. We show that NACP and tau aggregate into different filamentous components even if both proteins are incorporated into the same inclusions.

Transcriptional regulation of rat scavenger receptor class B type I gene

The scavenger receptor class B type I (SR-BI) mediates the selective transport of lipids from high density lipoprotein to cells and plays an important role in the reverse uptake of cholesterol to the liver and in the delivery of substrates for steroidogenesis in steroidogenic organs. We report here on the isolation and characterization of the upstream promoter region of the rat SR-BI gene. The transcription start site for rat SR-BI was mapped, and DNA sequence analysis revealed the presence of binding sites for the Sp1 family in the proximal 5'-flanking region. Analysis of deletion mutants with different 5' lengths revealed that the region between -121 and -90 base pairs from the transcription start site is essential for the efficient transcription of SR-BI. Both Sp1 and Sp3 bind to three GC boxes in the region (-141 to -1 base pairs) in a sequence-specific manner. Mutations in any of the GC boxes decreased efficient transcription from this promoter in MA-10 mouse Leydig tumor cells. The overexpression of Sp1 or Sp3 protein enhanced the rat SR-BI promoter activity. These results indicate that Sp1 family members of transcription factors are essential for transcription of the rat SR-BI gene.

Endothelial nitric oxide synthase gene mutation and human leukocyte antigen analyzed in three cases of familial vasospastic angina pectoris

A 50-year-old woman with rest angina underwent cardiac catheterization; coronary angiography in the presence of acetylcholine revealed 99% coronary spasm of the proximal left anterior descending artery. The patient's 82-year-old mother was also admitted to hospital with rest angina. Her Holter electrocardiogram showed ST-segment elevation during the attack at rest and coronary angiography showed 99% spasm of the right coronary artery and 90% spasm of the left coronary artery. Both women complained of chest pain during the spasm, which was accompanied by ST-segment depression. The 62-year-old brother of the original patient was also found to have coronary spasm of the left coronary artery. Human leukocyte antigen was analyzed in the 2 women: A2, B51, CW1, DR8 and DQ1 were common factors. A Glu298Asp point mutation of the endothelial nitric oxide synthase gene was investigated in both parents, their 2 daughters and 2 sons, but was not detected in the 3 patients, and was detected only in the 90-year-old father who did not suffer from angina. Nor was the T-786-C mutation found in the 3 cases. Other causes of familial spasm need to be elucidated.

Direct evidence for in vivo hydroxyl radical generation in blood of mice after acute chromium(VI) intake: electron spin resonance spin-trapping investigation

Although it is assumed from in vitro experiments that the hydroxyl radical (*OH) may be responsible for chromium(VI) toxicity/carcinogenicity, no electron spin resonance (ESR) evidence for the generation of *OH in vivo has been reported. In this study, we have employed an ESR spin-trapping technique with 5,5-dimethylpyrroline-N-oxide (DMPO), a selective *OH trap, to detect *OH in blood. The ESR spectrum of spin adduct observed in the blood of mice given 4.8 mmol Cr(VI)/kg body weight exhibited the 1:2:2:1 intensity pattern of a quartet with a hyperfine coupling constant A(N) = A(H) = 14.81 G and g-value = 2.0067. The concentration of the spin adduct detected in the blood was 7.37 microM. The adduct production was inhibited by the addition of specific *OH scavengers such as sodium benzoate and methional to the blood. The results indicate that the spin adduct is nitroxide produced by the reaction of *OH with DMPO. This is the first report of ESR evidence for the in vivo generation of *OH in mammals by Cr(VI).

[A case report of central respiratory failure due to hemimedullary syndrome]

A hemimedullary infarction, in which both medial and lateral medullary infarctions occur simultaneously, is a rare cerebrovascular disease. Pontomedullary lesions often cause central respiratory failure, and the majority of central respiratory failures are due to bilateral pontomedullary lesions. We report a 66-year-old man with central respiratory failure due to a hemimedullary infarction detected by magnetic resonance imaging. He was admitted to our hospital on March 7, 1998, because of a sudden onset of dysarthria, and both numbness and weakness on his left side. Soon after arriving at the hospital, his spontaneous respiration ceased. Therefore, he was intubated and artificial ventilation was started. Pertinent neurological abnormalities on admission consisted of dysarthria, dysphagia, right Horner's sign, right gaze evoked horizontal nystagmus, right soft palate palsy, and tongue deviation to the right. In addition, left hemiparesis, left Babinski's sign, sensory impairment on the left side including the face, and central respiratory failure were noted. Although voluntary respiration recovered in 12 days, sleep apnea continued for 5 months, which was considered to be due to the automatic respiratory failure. An important feature of this patient was that the hemimedullary infarction caused the central respiratory failure. To our knowledge, this is the third patient whose central respiratory failure occurred because of a hemimedullary infarction.

In vivo singlet-oxygen generation in blood of chromium(VI)-treated mice: an electron spin resonance spin-trapping study

Although it is assumed from in vitro experiments that the generation of reactive oxygen species such as the singlet oxygen (1O2), the hydroxyl radical, and the superoxide anion are responsible for chromium(VI) toxicity/carcinogenicity, no electron spin resonance (ESR) evidence for the generation of 1O2 in vivo has been reported. In this study, we have employed an ESR spin-trapping technique with 2,2,6,6-tetramethyl-4-piperidone (TMPD), a specific 1O2 trap, to detect 1O2 in blood. The ESR spectrum of the spin adduct observed in the blood of mice given 4.8 mmol Cr(VI)/kg body weight exhibited the 1:1:1 intensity pattern of three lines with a hyperfine coupling constant A(N) = 16.08 G and a g-value = 2.0066. The concentration of spin adduct detected in the blood was 1.46 microM (0.1% of total Cr concentration). The adduct production was inhibited by the addition of specific 1O2 scavengers such as 1,4-diazabicyclo[2.2.2]octane and sodium azide to the blood. The results indicate that the spin adduct is nitroxide produced by the reaction of 1O2 with TMPD. This is the first report of ESR evidence for the in vivo generation of 1O2 in mammals by Cr(VI).

SBP, SECIS binding protein, binds to the RNA fragment upstream of the Sec UGA codon in glutathione peroxidase mRNA

In mammals, most of the selenium contained in the body is present as an unusual amino acid, selenocysteine (Sec), whose codon is UGA. Because the UGA codon is typically recognized as a translation stop signal, it is intriguing how a cell recognizes and distinguishes a UGA Sec codon from a UGA stop codon. For eukaryotic selenoprotein mRNAs, it has been proposed that a conserved stem-loop structure designated the Sec insertion sequence (SECIS) in the 3'-untranslated (3'-UTR) region is required for recognition of UGA as a Sec codon. Some proteins which bind to SECIS (SBP) have been reported. However, it is not clear how the SECIS element in the 3'-UTR can mediate Sec insertion far at the in-frame UGA Sec codons. The idea that there must be a signal near the UGA Sec codon is still considered. Therefore, we searched for a protein which binds to an RNA sequence surrounding the UGA Sec codon on human glutathione peroxidase (GPx) mRNA. We found a protein which strongly bound to the RNA fragment upstream of the UGA Sec codon. However, this protein did not bind to the RNA sequence downstream of the UGA codon. This protein also bound to the SECIS sequence in the 3'-UTR of human GPx, and this binding to SECIS was competed with the RNA fragment upstream of the UGA Sec codon. Comparison of the RNA fragment with the SECIS fragment identified the conserved regions, which appeared in the region upstream of the in-frame UGA Sec codon of Se-protein mRNAs. Thus, this study proposes a novel model to understand the mechanisms of Sec incorporation at the UGA Sec codon, especially the regions upstream of the UGA codon of mRNAs of mammalian selenoproteins. This model explains that the stem-loop structure covering the UGA codon is recognized by SBP and how the UGA Sec codon escapes from attack by eRF of the peptide releasing factor.

[Diffuse left ventricular hypokinesis mimicking dilated cardiomyopathy with multi-vessel coronary vasospasm]

We investigated 7 patients with multi-vessel coronary vasospasm (> or = 75%) and diffuse left ventricular hypokinesis by coronary angiography and echocardiography. Four patients were male and 3 were female and mean +/- SD age was 63.0 +/- 11.2 years. Chief complaints were dyspnea in 3 patients, and chest pain, appetite loss, palpitation and general fatigue in one each. New York Heart Association functional classification was I in one patient, II in 5 and III in one. Mean heart rate was 73.9 +/- 11.6 beats/min. Initial echocardiography showed left ventricular end-diastolic diameter (LVDd) 54.4 +/- 5.5 mm, left ventricular end-systolic diameter (LVDs) 43.7 +/- 4.8 mm and percentage fractional shortening (%FS) 19.7 +/- 2.6%. The left ventricle was not remarkably enlarged despite poor contraction. Coronary vasospasm was induced after acetylcholine injection into the right coronary artery in 6 patients, left anterior descending artery in 7 and circumflex artery in 5. Four patients developed three-vessel coronary vasospasm. Three patients underwent endomyocardial biopsy which showed non-specific mild fibrosis. They were treated with nitrates and/or Ca-antagonists to prevent coronary vasospasm. Follow-up echocardiography was performed in 6 patients after 8.5 +/- 6.6 months. Echocardiography revealed marked improvement in left ventricular contraction (LVDd 49.7 +/- 4.6 mm, LVDs 35.8 +/- 4.4 mm, p < 0.05; %FS 27.9 +/- 4.5%, p < 0.05). These data suggested that left ventricular dilation was not prominent despite the poor contractility in patients with multi-vessel coronary vasospasm and diffuse left ventricular hypokinesis. The left ventricular dysfunction might be hibernating myocardium produced by multiple episodes of coronary vasospasm. Anti-vasospastic agents were effective in these patients.

Identification of the primary auditory field in archival human brain tissue via immunocytochemistry of parvalbumin

Using parvalbumin (PV)-immunocytochemistry, we identified the human primary auditory field (PAF) for the first time. The first gyrus of the right Heschl was identified, and a serial perpendicular cut to the gyrus was made. PV-immunoreactive neuropils delineated four zones, as have been described in monkeys. Unlike with conventional staining, zone 1, characterized by intense immunostaining, corresponded to the koniocortex (PAF), while zone 2, characterized by moderate immunostaining around zone 1, to the parakoniocortex. PV-immunocytochemistry was a useful way to identify PAF in formaline-fixed archival human brain tissue.

Scaled clips for aneurysm surgery: technical note

OBJECTIVE

The tips of clip blades are often invisible during operations on large, deep, or posteriorly projecting aneurysms. To overcome this problem, we sought to develop a series of scaled clips.

METHODS

We made scaled clips modified from Yaşargil titanium clips. The blades of the new clips are scaled every 5 mm from the tips with alternating colors. We have added six new types of straight scaled clips.

RESULTS

To date, we have performed approximately 40 aneurysm clippings using the new scaled clips and have confirmed their usefulness.

CONCLUSION

Scaling on the blades helps confirm accurate placement of a clip, even during operations for large, deep, or posteriorly projecting aneurysms, in which blade tips are often invisible.

Factors influencing survival in 33 patients undergoing resection of hepatic metastases from colorectal cancer

BACKGROUND/AIMS

To determine the factors influencing the prognosis of patients undergoing resection of hepatic metastases from colorectal cancer.

METHODOLOGY

Between December 1981 and March 1998, 33 patients underwent potentially curative hepatic resection for metastatic colorectal cancer at the Kiryu Kousei General Hospital. We retrospectively examined 15 factors, including 3 clinical factors, 5 primary tumor characteristics and 7 metastatic tumor characteristics. Survival rates were estimated by the Kaplan-Meier method, and the weighting of each factor was compared by the log-rank test. We used univariate and multivariate analyses to assess any associations between the factors and mortality.

RESULTS

The 30-day operative mortality was 0%. The 5-yr survival rate of the 33 patients was 43%. A significant survival advantage was noted in patients with 1 or 2 metastatic lesions (25/33, 76%), patients who underwent systematic anatomical resection (14/33, 42%) and male patients (16/33, 48%), compared with patients with 3 or more lesions (50% and 17%, P = 0.021), patients who underwent non-systematic resection (67% and 23%, P = 0.005) and female patients (65% and 20%, P = 0.011), respectively. No statistical influence on survival was found in the multivariate analysis of these 3 factors. Recurrence was identified in 24 patients (73%) and 19 of them died of recurrent cancer.

CONCLUSIONS

Surgical resection of hepatic metastases from colorectal cancer is safe and potentially curative in appropriately selected patients.

[Hepatotoxicity induction in mice after acute DL-lactic acid intake]

DL-Lactic acid and its salts are added to food as acidulants, pH control agents, leavening agents, nutrient supplements and seasonings. However, the basic data concerning the safety and toxicity of these compounds are insufficient. In this article, we examined induction of hepatotoxicity and nephrotoxicity in mice after acute intake of DL-lactic acid. Body weight change, serum glutamic pyruvic transaminase (SGPT) activity, serum urea nitrogen (SUN) concentration, liver and kidney weights, and renal lipid peroxide level could not be affected significantly in mice at 4 h after intraperitoneal administration of DL-lactic acid at 1.2 mmol/kg, indicating no induction of toxicity in the liver and kidney. In contrast, at 20 h after the treatment, SGPT activity, liver weight and lipid peroxide level were enhanced significantly, suggesting induction of hepatotoxicity. However, SUN concentration, kidney weight and lipid peroxide level could not be affected significantly at 20 h after the treatment, indicating no induction of nephrotoxicity.

[In vivo toxicity, lipid peroxide lowering, and glutathione, ascorbic acid and copper elevation induced in mouse liver by low dose of oxine-copper, a fungicide]

While oxine-copper (OxCu) is generally used as an agricultural fungicide and induces a harmful effect on ecosystems, little information is available regarding a toxic effect of OxCu on mammals. In this article, we examined in vivo induction of toxicity and change of levels of glutathione and ascorbic acid, major biological antioxidants, lipid peroxide and copper (Cu) in liver and kidney 4 h and 24 h after intraperitoneal administration of OxCu at a low dose (0.05 mmol/kg) to mice. Increased hepatic ascorbic acid and Cu levels were found at 4 h after the treatment. In addition, body weight change was lowered and serum glutamic pyruvic transaminase activity was elevated significantly compared to control at 24 h after the treatment, suggesting induction of systemic and hepatic toxicity respectively. These were accompanied by lowered lipid peroxide level and enhanced glutathione, ascorbic acid and Cu levels in the mouse liver. On the other hand, OxCu induced no elevation in serum urea nitrogen concentration 4 h and 24 h after the treatment, suggesting no induction of nephrotoxicity, accompanied by no change in renal lipid peroxide, glutathione, ascorbic acid and Cu levels. These results suggest that hepatic Cu elevation may induce hepatotoxicity and no renal Cu elevation may lead to no induction of nephrotoxicity after the treatment with OxCu.

Clinicopathological features of non-atherosclerotic cerebral arterial trunk aneurysms

Internal elastic lamina (IEL) is the most vital structure of the cerebral arterial wall. Longstanding weakness of the IEL due to hemodynamic stress is compensated by adaptive intimal thickening. Formation of cerebral arterial trunk aneurysm is assumed to be the result of a break in the equilibrium between hemodynamic stress and the condition of the IEL and intima. Cerebral arterial trunk aneurysms unrelated to the branching zones have several lesional patterns of IEL and the state of intima. There is a strong relationship between the pathological features of aneurysms and their clinical courses. We attempt to delineate the concept of cerebral arterial trunk aneurysms including 'dissecting aneurysms' and 'fusiform aneurysms'.

[In vivo toxicity, and glutathione, ascorbic acid and copper level changes induced in mouse liver and kidney by copper(II) gluconate, a nutrient supplement]

While copper(II) gluconate (CuGL) is generally used as a nutrient supplement for infant foods and as an oral deodorant, little information is available regarding a toxic effect of CuGL on mammals. In this article, we examined in vivo induction of toxicity and change of level of glutathione and ascorbic acid, major biological antioxidants, lipid peroxide and copper (Cu) in liver and kidney 4 h after single intraperitoneal administration of CuGL at 0.05 and 0.10 mmol/kg to mice. Serum glutamic pyruvic transaminase (SGPT) activity, an indicator of hepatotoxicity, significantly increased compared to control in proportion to doses of CuGL. Hepatic level of glutathione measured as nonprotein sulfhydryl was not proportional to CuGL doses, but enhanced after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. Like SGPT activity, serum urea nitrogen (SUN) concentration, an indicator of nephrotoxicity, significantly increased in proportion to doses of CuGL. Renal glutathione level was not different from control after dosing of 0.05 mmol/kg and lowered by 0.10 mmol/kg. In both organs, relative organ weight and lipid peroxide level were not affected by the treatment with CuGL; ascorbic acid level was elevated after dosing of 0.05 mmol/kg and was not different from control after treatment with 0.10 mmol/kg; like SGPT activity and SUN concentration, Cu level significantly increased in proportion to doses of CuGL. These results suggest that in the liver and kidney after the treatment with CuGL Cu accumulated may induce toxicity, leading to level changes of glutathione and ascorbic acid and to no induction of oxidative damage.

Evidence for the involvement of N-methylthiourea, a ring cleavage metabolite, in the hepatotoxicity of methimazole in glutathione-depleted mice: structure-toxicity and metabolic studies

In mice depleted of GSH by treatment with buthionine sulfoximine (BSO), methimazole (2-mercapto-1-methylimidazole, MMI) causes liver injury characterized by centrilobular necrosis of hepatocytes and an increase in serum alanine transaminase (SALT) activity. MMI requires metabolic activation by both P450 monooxygenase and flavin-containing monooxygenase (FMO) before it produces the hepatotoxicity. MMI and its analogues were examined for the ability to increase SALT activity in GSH-depleted mice. Saturation of the C-4,5 double bond in MMI resulted in a complete loss of hepatotoxicity. Similarly, ring fusion of a benzene nucleus to the C-4,5 double bond, forming 2-mercapto-1-methylbenzimidazole, abolished the toxic potency. As for MMI, 2-mercapto-1,4,5-trimethylimidazole, and 2-mercapto-1-methyl-4, 5-di-n-propylimidazole, the toxic potency decreased with the increasing bulk of the 4- and 5-alkyl substituents. Furthermore, methylation of the thiol group of MMI totally reduced its toxicity. These structural requirements and the known toxicity of thiono-sulfur compounds led us to the hypothesis that MMI would undergo epoxidation of the C-4,5 double bond by P450 enzymes and, after being hydrolyzed, the resulting epoxide would be then decomposed to form N-methylthiourea, a proximate toxicant. Before N-methylthiourea would produce toxicity, it would be further biotransformed to its S-oxidized metabolites mainly by FMO. Evidence for this hypothesis was provided by the facts that N-methylthiourea and glyoxal as the accompanying fragment were identified as urinary metabolites in mice treated with MMI and that N-methylthiourea caused a marked increase in SALT activity when administered to mice in combination with BSO.

Anti-mutagenic structural modification by fluorine-substitution in highly mutagenic 4-methylquinoline derivatives

We have previously shown that fluorine-substitution at position 3 of quinoline deprived this molecule of mutagenicity, possibly due to interference with the yield of its metabolically activated form, the 1,4-hydrated 2,3-epoxide (enamine epoxide), which is directly responsible for the mutagenic modification of DNA. To further explore the possibility of a method for anti-mutagenic modification of mutagens by fluorine-substitution, 4-methylquinoline (4-MeQ), the most mutagenic form of all the quinoline derivatives examined so far, was used as a target in the present study. Five mono- and di-fluorinated derivatives of 4-MeQ, 2-fluoro-4-methylquinoline (2-F-4-MeQ), 6-F-4-MeQ, 7-F-4-MeQ, 2,6-difluoro-4-methylquinoline (2, 6-diF-4-MeQ), and 2,7-diF-4-MeQ, were subjected to analysis of their structure-mutagenicity relationships. The 2-fluorinated derivatives (2-F-4-MeQ, 2,6-diF-4-MeQ, and 2,7-diF-4-MeQ) were all non-mutagenic in the Ames test. 7-F-4-MeQ was as highly mutagenic as, and 6-F-4-MeQ was less mutagenic than non-fluorinated 4-MeQ. Metabolic studies were also conducted with 4-MeQ, 2-F-4-MeQ, 6-F-4-MeQ, and 7-F-4-MeQ, using a liver microsomal enzyme fraction prepared from the 3-methylcholanthrene-treated rat. The HPLC analytical data showed that, although the metabolic patterns (hydroxylation at 4-methyl group as a main metabolic pathway and 3-hydroxylation as a minor pathway) of these four F-MeQs were similar to one another, only the 3-hydroxy metabolite of 2-F-4-MeQ was not produced under the present experimental conditions employed. These results suggest that fluorine-substitution at position 2 of 4-MeQ inhibited the formation of the enamine epoxide in the pyridine moiety and deprived this molecule of mutagenicity as in the case of quinoline.