First observation of clusters for solvated tropylium ions

We have first observed clusters for solvated tropylium ions (Tr+(ROH)n) which were isolated from ROH-CH3CN (1:1 by vol.; R = Me, Et, and Prn) solutions by using a specially designed mass spectrometer and found the clear-cut essential features concerning the solvation structure around Tr+.

Long-term survival after surgical resection for pancreatic cancer

BACKGROUND/AIMS

Pancreatic cancer remains one of the most formidable tumors defying early detection and effective treatment. Long-term survivors, however, do exist after resection. We investigated the clinicopathologic features of patients with pancreatic cancer who survived more than 5 years to draw out some suggestions concerning the indication of surgical treatment.

METHODOLOGY

We studied the clinicopathologic features of 13 patients with pancreatic cancer who survived more than 5 years after resection. We reviewed their clinical records to investigate preoperative symptoms, serum tumor markers, operative findings, postoperative adjuvant therapy, and modes of recurrence and survival periods. Information on the location, size, histology and spread of the primary tumors were mainly obtained from pathology reports.

RESULTS

Histologic types of the long survivors included ductal adenocarcinoma of common type in 4 patients, mucinous noncystic adenocarcinoma in 2, intraductal papillary-mucinous carcinoma (invasive) in 4, undifferentiated carcinoma in 1, endocrine tumor (islet cell carcinoma) in 1 and acinar cell carcinoma in 1. All 4 cases of ductal adenocarcinoma of the common type showed a moderate invasion either to the retroperitoneum, the portal vein or the duodenum. Two patients with mucinous noncystic carcinoma attained a long survival despite extensive invasion of the pancreatic stroma, although one died of peritoneal carcinomatosis. Two of 4 patients with intraductal papillary-mucinous cancer (invasive) died of peritoneal dissemination 6 and 11 years after resection, respectively. Three patients with cancer of other special histologic types, i.e., undifferentiated, well-differentiated endocrine carcinoma and acinar cell carcinoma, showed invasion of the portal vein and splenic artery, involvement of the retroperitoneum and a metastatic tumor in the liver, respectively.

CONCLUSIONS

Whereas special histologic types including ductal variants tended to predispose to long-term survival, ductal adenocarcinoma of the common type had some chance of long survival even with invasion of the surrounding tissues.

Role of the NMDA receptor subunit in the expression of the discriminative stimulus effect induced by ketamine

Ketamine, which is a non-competitive NMDA receptor antagonist, has been used as a dissociative anesthetic agent. However, chronic use of ketamine produces psychotomimetic effects, such as nightmares, hallucination and delusion. Therefore, the present study was designed to ascertain the role of the NMDA receptor and sigma receptor in the discriminative stimulus effect induced by ketamine. Fischer 344 rats were trained to discriminate between ketamine (5 mg/kg, i.p.) and saline under a fixed-ratio 10 food-reinforced procedure. Non-competitive antagonists for both NR2A- and NR2B-containing NMDA receptors, such as phencyclidine (0.1--1 mg/kg, i.p.) and dizocilpine (3--30 microg/kg, i.p.), and the NR2A-containing NMDA receptor-preferred antagonist dextromethorphan (3--56 mg/kg, i.p.) fully substituted for the ketamine cue in a dose-dependent manner. By contrast, the NR2B-containing NMDA receptor antagonist ifenprodil (5--20 mg/kg, i.p.) exhibited no generalization. Additionally, the competitive NMDA antagonist 3-[(+/-)-2-carboxypiperazine-4-yl] propyl-1-phosphonic acid ((+/-)-CPP; 0.3--5.6 mg/kg, i.p.) and a sigma receptor ligand DTG (0.3--3 mg/kg, s.c.) displayed no generalization to the ketamine cue. These results suggest that NR1/NR2A subunit containing NMDA antagonism may be critical for the production of the ketamine cue.

A theoretical study of alcohol oxidation by ferrate

The conversion of methanol to formaldehyde mediated by ferrate (FeO(4)2-), monoprotonated ferrate (HFeO4-), and diprotonated ferrate (H2FeO4) is discussed with the hybrid B3LYP density functional theory (DFT) method. Diprotonated ferrate is the best mediator for the activation of the O-H and C-H bonds of methanol via two entrance reaction channels: (1) an addition-elimination mechanism that involves coordination of methanol to diprotonated ferrate; (2) a direct abstraction mechanism that involves H atom abstraction from the O-H or C-H bond of methanol. Within the framework of the polarizable continuum model (PCM), the energetic profiles of these reaction mechanisms in aqueous solution are calculated and investigated. In the addition-elimination mechanism, the O-H and C-H bonds of ligating methanol are cleaved by an oxo or hydroxo ligand, and therefore the way to the formation of formaldehyde is branched into four reaction pathways. The most favorable reaction pathway in the addition-elimination mechanism is initiated by an O-H cleavage via a four-centered transition state that leads to intermediate containing an Fe-O bond, followed by a C-H cleavage via a five-centered transition state to lead to formaldehyde complex. In the direct abstraction mechanism, the oxidation reaction can be initiated by a direct H atom abstraction from either the O-H or C-H bond, and it is branched into three pathways for the formation of formaldehyde. The most favorable reaction pathway in the direct abstraction mechanism is initiated by C-H activation that leads to organometallic intermediate containing an Fe-C bond, followed by a concerted H atom transfer from the OH group of methanol to an oxo ligand of ferrate. The first steps in both mechanisms are all competitive in energy, but due to the significant energetical stability of the organometallic intermediate, the most likely initial reaction in methanol oxidation by ferrate is the direct C-H bond cleavage.

Hepatocarcinogenesis inhibition by caffeine in ACI rats treated with 2-acetylaminofluorene

The inhibitory effects of caffeine have been demonstrated on the development of various organs in animals. The purpose of the present study was to examine the inhibitory effect of caffeine on hepatocarcinogenesis and to determine the responsive dose of caffeine on hepatocarcinogenesis in young male ACI rats. Animals given a diet containing 2-acetylaminofluorene (2-AAF) for 12 weeks and then a basal diet and tap water containing caffeine for 18 weeks showed statistically significant decreases in the incidence, multiplicity (the number of hepatic tumors per rat) and histological grade compared with rats fed a diet containing carcinogen for 12 weeks followed by tap water alone. Dose-dependent inhibition of hepatocarcinogenesis by caffeine was also seen. The inhibitory effect of caffeine on hepatocarcinogenesis in rats was found when caffeine was administered during the initiation phase.

Seroepidemiological study of hepatitis E virus infection in Japan using a newly developed antibody assay

PURPOSE

A seroepidemiological study of hepatitis E virus (HEV) infection was conducted in Japan, where HEV infection is not considered endemic.

METHODS

IgG and IgM class antibodies to HEV were measured with a newly developed enzyme-linked immunosorbent assay in which recombinant virus-like particles were used as an antigen. A total of 1253 individuals (401 males and 852 females; age range, 6-89 years) were enrolled from two different areas: area 1 (n = 478), in which hepatitis C was endemic; and area 2 (n = 775), in which it was not endemic.

RESULTS

The HEV antibody (IgG class) positive rate was 6.7% in area 1 and 4.6% in area 2. Similarly, the HAV antibody (IgG class) positive rates were 65.3% and 72.3%. The age- and sex-specific prevalence of both HAV and HEV antibodies was quite similar in the two areas, and the HAV antibody positive rate clearly increased with age in both males and females. On the other hand, the HEV antibody positive rate showed a slight tendency to increase with age in males, but not in females. None of the 32 individuals with the HEV antibody who were interviewed had a history of visiting countries in which hepatitis E was endemic. In both areas, the mean age, percentage of males, and HAV antibody positive rate were significantly higher in the group of individuals with the HEV antibody than in the group of those without it, according to conventional statistical analyses. Of the three factors age, male sex, presence of HAV antibody, and the area factor, only male sex was statistically significant (P < 0.001) on multivariate logistic regression analysis. Two (0.2%) of the total of 1253 individuals were positive for the IgM class antibody to HEV.

CONCLUSIONS

Our results suggest the possibility that HEV infection is circulating in Japan at a low level. HEV infection was associated with male sex, but not with HAV infection.

Plant hormone regulation on scopoletin metabolism from culture medium into tobacco cells

Tobacco (Nicotiana tabacum L. Bright Yellow) T-13 cell line has an ability for production of scopoletin. In this cell culture, scopoletin is taken up from culture medium and accumulated in vacuoles after conversion to scopolin when cells are treated with 2,4-dichlorophenoxyacetic acid (2,4-D) (Taguchi et al. (2000)). To clarify the effect of 2,4-D on tobacco cells, its interaction with several other plant hormones was investigated. Other auxins also stimulated the uptake in the same manner as 2,4-D did, although higher concentrations were required than that of 2,4-D. When p-chlorophenoxyisobutyric acid (PCIB), an antiauxin, was added to the cell culture before 2,4-D, it inhibited 2,4-D-stimulated scopoletin uptake. This result suggests that the stimulation of scopoletin uptake was one of the auxin effects on tobacco cells. Among other classes of plant hormones that were tested, only salicylic acid stimulated the uptake. When these hormones were added to the cell cultures before 2,4-D, methyl jasmonate and kinetin reduced scopoletin uptake. These results suggest that this scopoletin uptake by tobacco cells is regulated by the interaction between different plant hormones.

Persistent infection mechanism of GB virus C/hepatitis G virus differs from that of hepatitis C virus

OBJECTIVE

Changes in the deduced amino acid sequence of the envelope 2 (E2) region of the GB virus C/hepatitis G virus (GBV-C/HGV) were analyzed to investigate whether or not the region contributes to persistent infection with the virus.

METHODS

Eight patients with acute hepatitis C and 1 patient with acute hepatitis of unknown etiology were included in the study. GBV-C/HGV RNA was detected in 6 patients, including the patient with hepatitis of unknown origin. The nucleotide sequence of the E2 region of hepatitis C virus (HCV) and GBV-C/HGV was determined by direct sequencing of polymerase chain reaction products in 5 patients with HCV infection and in 6 patients with GBV-C/HGV infection twice during the period of early infection and several months or years later in each patient.

RESULTS

The mean substitution rate of the deduced amino acid sequence in the E2 region was over 100 times lower (p < 0.001) in GBV-C/HGV (0.01 +/- 0.04/month/100 sites) than in HCV (2.4 +/- 1.7/month/100 sites). The amino acid sequence of the loop domain of GBV-C/HGV-E2 did not change in any of the 6 patients. On the other hand, the sequence of the hypervariable region of HCV-E2 changed remarkably (5.9 +/- 4.3/month/100 sites). No amino acid substitution in the loop domain was observed in 7 additional patients who showed persistent GBV-C/HGV viremia for more than 2 years.

CONCLUSION

These results indicate that changes in the amino acid sequence of the E2 region are not involved in the mechanism of persistent GBV-C/HGV infection.

Non-point pollution of Ishikari river, Hokkaido, Japan

We researched the Ishikari river, Japan's second-longest river, to clarify the characteristics of non-point pollution by comparing flux characteristics of chemical components in three periods of one year: the snow melting period, the typhoon flooding period and the stable period. We found non-point pollutants present in great amounts because a large amount of suspended matter, which is contained in soil, flows into the river and concentrations of nutrients and organic matters do not decrease in a short time in the flooding period by rain and in the snow melting period.

Caspase-3 inhibitor rescues N -methyl- N -nitrosourea-induced retinal degeneration in Sprague-Dawley rats

The effect of a caspase-3 inhibitor on N -methyl- N -nitrosourea (MNU)-induced retinal degeneration was investigated. Sixty mg kg(-1)MNU was given intraperitoneally to 50 day old female Sprague-Dawley rats, and 4000 ng Ac-DEVD-CHO, a caspase-3 inhibitor, was injected intravitreally twice at 0 and 10 hr after MNU. In both peripheral and central retina, an apoptotic index of the photoreceptor cells 24 hr after MNU treatment was calculated by TUNEL labeling, and retinal damage 7 days after MNU treatment was evaluated from retinal thickness and a retinal damage ratio (length of damaged retina : whole retinal length). In MNU-treated rats, the TUNEL index 24 hr post-MNU was 79.5% in the peripheral and 83.7% in the central retina, while the Ac-DEVD-CHO injection significantly reduced it to 59.7 and 71.8%, respectively. Total retinal thickness 7 days after MNU was 38 microm in the peripheral and 75 microm in the central retina. Ac-DEVD-CHO injection increased these values to 72 and 77 microm, respectively. The retinal damage ratio 7 days after MNU was 98.5%. Ac-DEVD-CHO injection significantly reduced this value to 54.4%. The use of a caspase-3 inhibitor was effective in the suppression of MNU-induced retinal apoptosis and may be a therapeutic intervention in human retinitis pigmentosa.

The electronic and vibrational structures of iron-oxo porphyrin with a methoxide or cysteinate axial ligand

Hybrid density functional theory (DFT) calculations for the electronic and vibrational structures of compound I species with a methoxide (MeO-) (1) or cysteinate (CysS-) (2) axial ligand are carried out in order to elucidate the natures of a methoxide-coordinating new type of compound I species (Bull. Chem. Soc. Jpn. 71 (1998) 1343) and cysteinate-coordinating compound I species of chloroperoxidase (CPO-I) and cytochrome P450s (P450-I). DFT computations of 1 and 2 demonstrate that these "anionic" ligands are a spin carrier; 70% (80%) of a spin density resides on the O (S) atom of the axial ligand and 30% (20%) is distributed on the porphyrin ring. These results suggest that for the generation of the compound I species, one electron is removed from the iron centers and the rest of the one electron is supplied from the oxidizable axial ligands instead of the iron centers or the porphyrin ring. Vibrational analyses demonstrate that the Fe=O bond is more strongly activated in 1 compared with 2 with the stretching mode at 849 cm(-1) (878 cm(-1)) for the doublet state1a (2a) and at 814 cm(-1) (875 cm(-1)) in the quartet state 1b (2b). This reverse order of the Fe=O bond strength with respect to the axial donor strength should have relevance to the significantly oxidized character of the CysS- axial ligand. In conjunction with the recent results of the extensive resonance Raman (RR) studies, some interpretations of unsettled RR results for compound I of chloroperoxidase (CPO-I) and a synthetic compound I species [O=FeIV(TMP*+)(alcohol)] (J. Am. Chem. Soc. 113 (1991) 6542) concerning the O=Fe stretching frequencies are discussed.

Clinical impact of genotype 1 TT virus infection in patients with chronic hepatitis C and response of TT virus to alpha-interferon

BACKGROUND

The relationship between genotype 1 TT virus (TTV) infection and the status of chronic hepatitis C was studied.

METHODS

A total of 52 patients with chronic hepatitis C who were treated with interferon (IFN)-alpha were enrolled in the present study. Of those, 12 were infected with genotype 1 TTV and 40 were uninfected.

RESULTS

Clinical backgrounds, including mean age, sex, blood transfusion history, serum alanine aminotransferase (ALT) level, and the results of liver biopsy did not differ between patients with and without genotype 1 TTV infection. The distribution of hepatitis C virus (HCV) genotypes did not differ between the two groups of patients, but TTV-infected patients tended to have a lower serum HCV-RNA level than uninfected patients (median (range) 26.0 (< 1-460) vs 135 (1.2-740) kilo copies/mL, respectively; P = 0.065). Patients with a sustained response of HCV to IFN-alpha were significantly more common in TTV-infected than -uninfected patients (58 vs 23%, respectively; P = 0.018). Multivariate logistic regression analysis revealed that patients with a sustained response of HCV correlated significantly with the serum HCV-RNA level (P = 0.006), but not with the presence or absence of genotype 1 TTV infection (P = 0.161). Serum TTV-DNA decreased with IFN-alpha therapy in all 12 patients and remained negative in six patients even after treatment. There was no correlation between patients with a sustained response of HCV and the same of TTV. Serum ALT levels correlated with changes in the status of HCV viremia, but not with changes in the status of TTV viremia.

CONCLUSIONS

An opposing relationship between HCV and TTV proliferation was suggested, but coinfection with genotype 1 TTV did not affect the status of chronic hepatitis C.

Clinical impact of genotype 1 TT virus infection in patients with chronic hepatitis C and response of TT virus to alpha-interferon

BACKGROUND

The relationship between genotype 1 TT virus (TTV) infection and the status of chronic hepatitis C was studied.

METHODS

A total of 52 patients with chronic hepatitis C who were treated with interferon (IFN)-alpha were enrolled in the present study. Of those, 12 were infected with genotype 1 TTV and 40 were uninfected.

RESULTS

Clinical backgrounds, including mean age, sex, blood transfusion history, serum alanine aminotransferase (ALT) level, and the results of liver biopsy did not differ between patients with and without genotype 1 TTV infection. The distribution of hepatitis C virus (HCV) genotypes did not differ between the two groups of patients, but TTV-infected patients tended to have a lower serum HCV-RNA level than uninfected patients (median (range) 26.0 (< 1-460) vs 135 (1.2-740) kilo copies/mL, respectively; P = 0.065). Patients with a sustained response of HCV to IFN-alpha were significantly more common in TTV-infected than -uninfected patients (58 vs 23%, respectively; P = 0.018). Multivariate logistic regression analysis revealed that patients with a sustained response of HCV correlated significantly with the serum HCV-RNA level (P = 0.006), but not with the presence or absence of genotype 1 TTV infection (P = 0.161). Serum TTV-DNA decreased with IFN-alpha therapy in all 12 patients and remained negative in six patients even after treatment. There was no correlation between patients with a sustained response of HCV and the same of TTV. Serum ALT levels correlated with changes in the status of HCV viremia, but not with changes in the status of TTV viremia.

CONCLUSIONS

An opposing relationship between HCV and TTV proliferation was suggested, but coinfection with genotype 1 TTV did not affect the status of chronic hepatitis C.

Synthesis, structure, and H2O2-dependent catalytic functions of disulfide-bridged dicopper(I) and related thioether-copper(I) and thioether-copper(II) complexes

A disulfide-bridged dicopper(I) complex, [Cu2(Py2SSPy2)](ClO4)2 (1) (Py2SSPy2 = bis(2-[N,N-bis(2-pyridylethyl)-amino]-1,1- dimethylethyl)disulfide), a thioether-copper(I) complex, [Cu(iPrSPy2)](ClO4) (2) (iPrSPy2 = N-(2-isopropylthio-2-methyl)propyl-N,N-bis-2-(2-pyridyl)ethylamine, and a thioether-copper(II) complex, [Cu-(PheSPy2)(H2O)](ClO4)2 (3) (PheSPy2 = N-(2-methyl-2-phenethylthio)propyl-N,N-bis-2-(2- pyridyl)ethylamine), were newly synthesized by the reactions of Cu(ClO4)2.6H2O with a thiol ligand of Py2SH (N,N-bis[2-(2-pyridyl)-ethyl]-1,1-dimethyl-2- mercaptoethylamine) and thioether ligands of iPrSPy2 and PheSPy2, respectively. For complexes 1 and 2, X-ray analyses were performed. Complex 1 crystallizes in the triclinic space group P1, and complex 2 crystallizes in the orthorhombic space group Pbca with the following unit cell parameters: for 1, a = 15.165 (3) A, b = 22.185 (4) A, c = 14.989 (3) A, alpha = 105.76 (1) degrees, beta = 90.82 (2) degrees, gamma = 75.23 (1) degrees, and Z = 2; for 2, a = 17.78 (2) A, b = 17.70 (1) A, c = 15.75 (1) A, and Z = 8. Complex 1 is the first structurally characterized example obtained by the redox reaction Cu(II) + RSH-->Cu(I) + RSSR and has two independent structures (1a, 1b) which mainly differ in S-S bond distances, Cu(I)...Cu(I) separations, and C-S-S-C dihedral angles of the disulfide units. The S-S bond distances of 2.088(7) A in 1a and 2.070(7) A in 1b are indicative of significant activation of the S-S bonds by the dicopper centers. Fragment molecular orbital (FMO) analyses and molecular orbital overlap population (MOOP) analyses based on the extended Hückel method clarify the preferable formation of the disulfide S-S bond in 1 rather than the formation of a thiolate-copper(II) complex within the Py2S- ligand framework. Catalytic functions of complexes 1-3 were investigated with peroxides (H2O2 and tBuOOH) as oxidants. Complex 1 catalyzed the selective oxidation of cyclohexane to cyclohexanol and mediated the cyclohexene epoxidation in the presence of H2O2. A transient dark green intermediate observed in the reaction of 1 with H2O2 is characterized by UV-vis, EPR, and resonance Raman spectroscopies, identifying it as a Cu(II)-OOH species, 1(OOH). The resonance Raman features of the nu(O-O) bands at 822 and 836 cm-1, which are red-shifted to 781 and 791 cm-1, respectively, upon introduction of H2(18)O2, are indicative of formation of two kinds of Cu-OOH species rather than the Fermi doublet and the significant weakening of the O-O bonds. These mechanistic studies demonstrate that by virtue of the electron-donating ability of the disulfide unit the Cu-OOH species can be actually activated for one-electron oxidation, which has been reported so far unfavorable for other vibrationally characterized Cu-OOH species.

Cataractogenesis in neonatal Sprague-Dawley rats by N-methyl-N-nitrosourea

Cataract was induced by a single intraperitoneal injection of 100 mg/kg N-methyl-N-nitrosourea (MNU) to 0-, 5-, 10-, 15-, or 20-day-old male and female Sprague-Dawley rats. In day 0, 5, 10, and 15 MNU-treated rats, mature cataracts were constantly seen 7, 14, 14, and 30 days after dosing, respectively. In the day 20 MNU-treated rats, only subcapsular cataract was seen 30 days after dosing. Therefore, the rats exposed to MNU at an earlier age caused cataract more rapidly and severely. In the day 0 MNU-treated rats, 7-methyldeoxyguanosine DNA adduct was detected in the lens epithelial nuclei 12 hours after MNU dosing, followed by apoptosis, which was confirmed by morphology, by TUNEL signals, and by DNA ladder and peaked 3 days after MNU dosing. In the apoptosis cascade, upregulation of Bax, downregulation of Bcl-2, and increased CPP32 protease (caspase-3) activity were seen 12 hours after MNU dosing. Therefore, the pathogenesis of MNU-induced cataract was associated with DNA adduct formation in the lens epithelial cell nuclei leading to apoptosis by upregulation of Bax protein, downmodulation of Bcl-2 protein, and activation of caspase-3.

T cell repertoire in the liver of patients with primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune chronic liver disease characterized by the destruction of the bile ducts with an accumulation of lymphocytes. To investigate the roles of T cells accumulating around the bile ducts, we analyzed the clonality of alphabeta T cell populations in the livers of patients with PBC by size spectratyping and sequencing of the T cell receptor (TCR) Vbeta transcripts.TCR Vbeta spectratyping of PBC patients showed several skewed complementarity determining region 3 (CDR3) size patterns suggestive of clonal predominance as well as Gaussian-like patterns suggestive of polyclonal expansion. We observed Vbeta4 clones sharing the Gly (G)-G motif in the CDR3 nDn regions and a Vbeta4-Jbeta2.7 combination in three patients bearing HLA-DR2 and -DQ1. G-Leu (L)-Ala (A) or G-L motifs were also seen in the nDn regions of Vbeta17 with Jbeta2.1 of the two patients having HLA-A26. However, there were no whole CDR3-shared clones in any of the patients. In conclusion, we have observed that T cell clones are heterogeneous in each patient, but that they have some common motifs in the TCR Vbeta CDR3. We strongly suggest that these clonally expanded T cells might be involved in the immunopathogenesis of PBC.

Analysis of T cell repertoire in the liver of patients with chronic hepatitis C

Many T cells infiltrate into the liver of patients with chronic hepatitis C (CH-C). They are believed to play a crucial role in the immunopathogenesis of hepatic inflammation, but their clonality and specificity are unknown. The aim of this study was to clarify the characteristics of these T cells. We analysed the complementarity-determining region (CDR)3 size lengths of T cell receptor (TCR) beta-chains by size spectratyping, and determined the sequences of Vbeta CDR3 after subcloning Vbeta-specific polymerase chain reaction products. Spectratyping showed clonal expansions in all liver specimens, most of which showed more than two T cell clones. Moreover, many non-clonal T cells also accumulated in the liver. Clonality of the T cells suspected by spectratyping was confirmed by CDR3 sequencing. Although the sequences revealed no whole CDR3-shared clones among different patients, some common motif sequences were observed. Our data suggest that T cells are stimulated by several hepatitis C virus (HCV) epitopes, then accumulate in the liver of CH-C patients. Shared motifs of expanded T cell clones suggest that they might recognize the same regions of HCV peptides, but have differences due to HCV peptide mutational changes. These clones might also interact with non-clonal T cells and play a crucial role in the immunopathogenesis of CH-C.

Retinal damage induced by cisplatin in neonatal rats and mice

PURPOSE

The morphologic response of the retina at different neonatal ages to various doses of cis-platinum(II)diamminedichloride (cisplatin) was examined in rats and mice.

METHODS

Cisplatin was given to rats at a dose of 1, 3 or 5 mg/kg at 0 days or 5 mg/kg at 7 or 14 days of age, and to mice at 0.5, 1.5, 3 or 6 mg/kg at 0 days or 6 mg/kg at 7 or 14 days of age, and the animals examined 12 and 24 hrs, and 3 and 7 days after the treatment.

RESULTS

In both species, regardless of gender, with > or = 3 mg/kg cisplatin treatment (lethal dose) at day 0, retinal damage characterized by the appearance of aggregations of TUNEL-positive cells scattered in the undifferentiated neuroblastic layer was seen at 24 hrs, and led to rosette formation at day 3 and 7 (retinal dysplasia). At the ultrastructural level, neuroblastic cells showed condensation of chromatin and shrinkage of the cytoplasm, and rosettes encircled by an outer limiting membrane. Cell debris phagocytosed by pigment epithelial cells was seen. However, cisplatin at < 3 mg/kg in 0-day-old animals or at high dose in > or = 7-day-old animals caused no damage to the retina.

CONCLUSIONS

A critical period (day 0) for the administration and a threshold dose (> or =3 mg/kg) of cisplatin in the development of retinal damage in rats and mice was seen. Although the cisplatin dose necessary to damage the retina caused a high incidence of mortality, it was below the human therapeutic dose.

A gene on SCA4 locus causes dominantly inherited pure cerebellar ataxia

BACKGROUND

Several different genes or their loci have been identified for autosomal dominant cerebellar ataxia (ADCA). However, other types of ataxia remain unassigned.

OBJECTIVE

To identify a new locus for ADCA.

METHODS

Six Japanese families with ADCA with pure cerebellar syndrome (ADCA type III) were examined. These families had been molecularly excluded for spinocerebellar ataxia (SCA) types 1 through 3, 5 through 8, and 10. Clinical examination was undertaken, and a genome-wide linkage search was performed on 250 microsatellite DNA markers.

RESULTS

Strong evidence for linkage was found with markers on human chromosome 16q, and haplotype and multipoint analyses further refined the gene locus in a 10.9-cM interval between D16S3089 and D16S515. Linkage disequilibrium was further found with the marker D16S3107 within the interval. The locus was exactly the candidate interval of SCA4, a rare form of ADCA clinically characterized by ataxia with sensory neuropathy and pyramidal tract signs. This would suggest that SCA4 and our ADCA type III are likely to be allelic disorders with different clinical features.

CONCLUSION

The current study provides evidence that a gene on the SCA4 locus causes a pure cerebellar syndrome.

Comedogenicity of squalene monohydroperoxide in the skin after topical application

The comedogenicity of squalene peroxides was examined on the rabbit ear skin after topical application of squalene-monohydroperoxide (Sq-OOH), the initial product when squalene was irradiated with UV-A. Since comedogenic products from UV-irradiated squalene were extracted with methanol solution, we isolated Sq-OOH by reverse-phased HPLC with a methanol mobile phase solvent. The degree of comedogenic reaction induced by Sq-OOH was higher than that of well-known comedogenic cosmetic ingredients. Unlike two other mono-peroxides, tert-butyl hydroperoxide and cumene-mono-hydroperoxide, Sq-OOH induced comedo-formation in the rabbit ear skin. However, the comedogenicity of reduced Sq-OOH, squalene-hydroxide (Sq-OH) and squalene itself was lower than that of Sq-OOH. These results indicate that Sq-OOH is a potent comedogenic mono-hydroperoxide chemical to rabbit skin.

Effects of EGF and TGF-alpha on invasion and proteinase expression of uterine cervical adenocarcinoma OMC-4 cells

Uterine cervical adenocarcinoma typically is an aggressive neoplasm with a propensity for early invasion and dissemination; however, the regulatory mechanism of invasive activity of cervical adenocarcinoma cells has not been fully understood. In this study, biological effects of epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha on invasion and proteinase expression of human cervical adenocarcinoma OMC-4 cells were investigated. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into the reconstituted basement membrane were stimulated by 0.1-10 nM EGF and TGF-alpha in a concentration-dependent manner. Their effects on tumor cell migration were also confirmed by wound assay. The zymography of tumor-conditioned medium showed that the treatment of OMC-4 cells with EGF and TGF-alpha resulted in the increase of matrix metalloproteinase (MMP)-2 and urokinase-type plasminogen activator (uPA). Matrilysin (MMP-7), also secreted by OMC-4 cells, was not affected by these growth factors. These results suggest that EGF and TGF-alpha act as positive regulators on the invasion of cervical adenocarcinoma cells, which may be associated with their stimulatory effects on tumor cell motility and the induction of type IV collagenase and uPA secreted by tumor cells.

Time-specific occurrence of alopecia in neonatal C57BL mice treated with N-methyl-N-nitrosourea and the therapeutic efficacy of tacrolimus hydrate

Alopecia was induced in male and female neonatal C57BL mice by a single intraperitoneal injection of 60 mg/kg N-methyl-N-nitrosourea (MNU). MNU administration was most effective in the 8-day-old mice and less effective in the 5-day-old mice (at active and early anagen stages of the first hair cycle, respectively). No alopecia was seen in the day 14 MNU-treated animals (at telogen stage of the first hair cycle). MNU effectively induced hair follicular cell apoptosis at the anagen stage by up-regulation of Bax protein without down-modulation of Bcl-2 protein. In day 8 MNU-treated mice, the immunosuppressive agent 0.01% tacrolimus hydrate (FK506), when topically applied for 5 days from 1 day after MNU treatment (before the occurrence of alopecia), decreased the severity of alopecia. However, it did not stimulate hair growth when applied for 5 days from 20 days of age (after occurrence of alopecia).

Cross-cultural traits for personality of patients with Parkinson's disease in Japan

Recent studies suggest that Parkinson's disease (PD) is associated with particular personality traits. Using Cloningers's Tridimensional Personality Questionnaire (TPQ), Menza and colleagues [1993: Neurology 43:505-508] reported a possible association between PD and a reduced score in the novelty seeking (NS) dimension of the TPQ. We sought to determine whether this association, which was found in a study conducted in the United States, could also be found among Japanese PD patients. We performed personality assessments of 67 Japanese PD patients, using the TPQ test. The results suggest that Japanese PD patients have significantly lower scores in the NS dimension of the TPQ, as well as significantly higher harm avoidance (HA) scores, compared with matched control subjects. Furthermore, the PD patients undergoing treatment for depression using antidepressant drugs scored significantly higher in the HA dimension than PD patients who did not receive antidepressant drug treatment. Our results suggest that the high HA score, and the low NS score in the TPQ test observed in patients with PD, is a cross-cultural phenomenon, although the influence of depression, long-term treatment, and premorbid gene/environmental interactions may also affect these personality traits. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:1-3, 2000.

Spontaneous remission of a solitary intraspinal synovial cyst of the lumbar spine

We report on a 15-year-old boy in whom a spontaneous remission of a symptomatic synovial cyst, possibly emanating from the L4-5 facet joint, was noted. The medical history suggested that sport-related overactivity and/or minor trauma was the underlying cause. Conservative treatment for several months may be one treatment option if the cyst wall is not calcified and the symptoms and signs related to radiculopathy show a gradual decrease.

Two-step concerted mechanism for methane hydroxylation on the diiron active site of soluble methane monooxygenase

A new concerted mechanism is proposed for the conversion of methane to methanol on intermediate Q of soluble methane monooxygenase (sMMO), the active site of which is considered to involve an Fe2(mu-O)2 diamond core. A hybrid density functional theory (DFT) method is used for our mechanistic study on the important reactivity of the bare FeO+ complex and a diiron model of intermediate Q. The reaction pathway for the methane hydroxylation on the diiron complex is essentially identical to that for the gas-phase reaction by the bare FeO+ complex. Methane is highly activated on the dinuclear iron model through the formation of a methane complex, in which a coordinatively unsaturated iron plays a central role in the bonding interaction between the diiron model and substrate methane. A H atom abstraction via a four-centered transition state and a recombination of the OH and CH3 groups via a three-centered transition state successively occur on the dinuclear iron-oxo species, leading to the formation of a methanol complex that corresponds to intermediate T. These electronic processes take place in a concerted manner. Our mechanism for methane hydroxylation by sMMO is different from the radical mechanism that has been widely accepted for enzymatic hydrocarbon hydroxylation, especially by cytochrome P450.

20-W ultraviolet-beam generation by fourth-harmonic generation of an all-solid-state laser

We have obtained UV power of 20.5 W with a repetition rate of 10 kHz by the use of a high-brightness high-power all-solid-state green laser and a high-quality CsLiB(6)O(10) crystal. This power is, to our knowledge, the highest UV power achieved so far in all-solid-state lasers.

Biological implications of growth factors on the mechanism of invasion in gynecological tumor cells

We investigated the effects of epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) on migration, invasion and proteinase expression of gynecological cultured cancer cells (SKG-IIIb cervical squamous cell carcinoma, OMC-4 cervical adenocarcinoma, SNG-M endometrial adenocarcinoma and OMC-3 ovarian adenocarcinoma), and whether these growth factors affect thymidine phosphorylase/platelet-derived endothelial cell growth factor expression of tumor cells. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were stimulated by 0.1-10 nM EGF and TGF-alpha in a concentration-dependent manner. The zymography of tumor-conditioned medium showed that the treatment of tumor cells with EGF and TGF-alpha resulted in the increase of type IV collagenases, stromelysin and urokinase-type plasminogen activator which was partly confirmed by immunoblot analysis. The expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor which has angiogenic activity, was also upregulated by these growth factors. These results suggest that EGF and TGF-alpha act as positive regulators on the invasion process of gynecological tumor cells which may be associated with their stimulatory action on the motility of tumor cells, the expression of proteinases secreted by tumor cells and the angiogenic phenotype.

Association between polymorphism of the cholecystokinin gene and idiopathic Parkinson's disease

Parkinson's disease (PD) is characterized by major alterations of neurotransmitter activity due to damage of the substantia nigra. Changes in neuropeptide concentration within the basal ganglia may play an important role in the putative dopaminergic-peptidergic interactions associated with the disease. Cholecystokinin (CCK) modulates the release of dopamine in the mesolimbic pathway and affects dopamine-related behavior. We analyzed genetic variations in the CCK gene, in both the coding and promoter region, in order to investigate the role of polymorphism in idiopathic PD. Four polymorphic sites of the CCK gene (-196G/A, -45C/T, 1270C/G, 6662C/T) were found in PD patients and controls. Complete linkage disequilibrium was observed between the -45 locus and the 1270 locus, and also a possible linkage disequilibrium was found between the -45 and -196 loci. A significant difference was found in the distributions of three identified genotypes at the -45 locus between 116 PD patients and 95 age-matched control subjects (chi2 = 7.95, p = 0.018, Bonferroni correction; p = 0.054). In addition, a significant difference was obtained amongst the three genotypic groups at the -45 locus when compared between PD patients who experienced hallucinations (n = 23) and those (n = 93) who did not (chi2 = 8.08, p = 0.018, Bonferroni correction, p = 0.126). Our data suggested that mutations at the -45 locus in the promoter region of the CCK gene may influence vulnerability to hallucinations in PD patients treated with L-dopa.

Mechanisms of photoreceptor cell apoptosis induced by N-methyl-N-nitrosourea in Sprague-Dawley rats

A single intraperitoneal injection of 75 mg/kg N-methyl-N-nitrosourea (MNU) was given to 50-day-old female Sprague-Dawley rats and examined sequentially 12 and 24 hours, and 3 and 7 days after MNU treatment. Photoreceptor cell death was evoked in all treated rats. After MNU treatment, 7-methyldeoxyguanosine DNA adduct was detected selectively in photoreceptor cell nuclei at 12 hours, followed by photoreceptor cell apoptosis as confirmed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-digoxigenin nick-end labeling signals which peaked at 24 hours and continued until day 7 when several layers of photoreceptor cell nuclei were left. In apoptosis cascade, down-regulation of Bcl-2 was seen at 12 hours and up-regulation of Bax was seen at 24 hours, and caspase family (caspase 3/CPP32, caspase 6/Mch2, and caspase 8/FLICE protease) activities peaked 72 hours after MNU treatment. Therefore MNU-induced photoreceptor cell death was attributed to DNA adduct formation restricted to photoreceptor cell nuclei leading to photoreceptor cell apoptosis by up-regulation of Bax protein, down-modulation of Bcl-2 protein, and activation of caspases 3, 6, and 8.

Direct participation of potassium ion in the catalysis of coenzyme B(12)-dependent diol dehydratase

The direct ion-dipolar interactions between potassium ion (K(+)) and the two hydroxyl groups of the substrate are the most striking feature of the crystal structure of coenzyme B(12)-dependent diol dehydratase. We carried out density-functional-theory computations to determine whether K(+) can assist the 1,2-shift of the hydroxyl group in the substrate-derived radical. Between a stepwise abstraction/recombination reaction proceeding via a direct hydroxide abstraction by K(+) and a concerted hydroxyl group migration assisted by K(+), only a transition state for the latter concerted mechanism was found from our computations. The barrier height for the transition state from the complexed radical decreases by only 2.3 kcal/mol upon coordination of the migrating hydroxyl group to K(+), which corresponds to a 42-fold rate acceleration at 37 degrees C. The net binding energy upon replacement of the K(+)-bound water for substrate was calculated to be 10.7 kcal/mol. It can be considered that such a large binding energy is at least partly used for the substrate-induced conformational changes in the enzyme that trigger the homolytic cleavage of the Co-C bond of the coenzyme and the subsequent catalysis by a radical mechanism. We propose here a new mechanism for diol dehydratase in which K(+) plays a direct role in the catalysis.

Detection of mutants in polio vaccine viruses using pooled antipoliovirus monoclonal antibodies

We prepared six monoclonal antibodies (mAbs) for type 1 polioviruses, and analysed their neutralizing specificities for use in safety tests in oral poliomyelitis vaccine (OPV) production. Pools of two or more individual mAbs showed high neutralizing activity against high-titre (approximately 10(7) CCID (50)/25 microl) of Sabin type 1 virus. It was demonstrated that the pooled mAbs can be utilized effectively in detection tests of adventitious viruses, which are among the safety tests in OPV production. Moreover, some pooled mAbs were shown to be capable of detecting very small amounts of type 1 virulent viruses and mutants in high-titre Sabin type 1 virus suspensions. Neutralizing antibody titres of these pooled mAbs decreased with increasing numbers of mutants containing neurovirulent activity in high-titre Sabin type 1 viruses which were repeatedly passaged in culture. It is expected that these pooled mAbs will contribute greatly to safety tests for OPV production.

T cell repertoire in the liver of patients with autoimmune hepatitis

Despite a large number of T cells infiltrating into the liver of patients with autoimmune hepatitis (AIH), little is known about their roles or target antigens. To investigate the roles of these T cells in the pathogenesis of AIH, we have studied the clonality of alphabeta T cell populations in liver tissue by size spectratyping the complementarity-determining region (CDR)3 size lengths of T cell receptor (TCR) Vbeta-chain transcripts. Analysis of nine AIH patients who had the HLA DR4 haplotype showed clonal expansion in all samples. More than two T cell clones expanded in most patients. Although the expression of the TCR Vbeta genes was different among the nine patients, clonal expansion of T cells expressing either TCR Vbeta2, 3, 4, 16, or 22 was observed in two patients or more. TCR Vbeta4 clones expanded in 5 cases. Cloning and sequencing of TCR Vbeta CDR3 from PCR products revealed no whole CDR3-shared clones among different patients. In conclusion, several T cell clonotypes first recognize target antigens, then expand and accumulate in the liver of AIH patients. These suggest heterogeneity of autoantigens and the complexity of AIH immunopathogenesis in individual patients.

An autopsy case of malignant mesothelioma with osseous and cartilaginous differentiation: bone morphogenetic protein-2 in mesothelial cells and its tumor

An autopsy case of biphasic malignant mesothelioma with osseous and cartilaginous differentiation diffusely involving the peritoneal cavity was confirmed by light microscopic histochemistry, immunohistochemistry, and electron microscopy. A reverse transcription-polymerase chain reaction using specific primers for bone morphogenetic protein-2 (BMP-2) revealed weak positive transcript in normal mesothelial cells and up-regulated expression around bone-forming malignant mesothelioma tissue. However, BMP-2 protein expression was detected only in the marginal zone of bone trabeculae and spindle-shaped mesothelioma cells distributed around bone trabeculae in tumor tissue. The distribution of type IV collagen in tumor tissue was in accordance with the BMP-2 expression. Normal mesothelial cells and tumor cells expressed BMP-2 mRNA, but the BMP-2 protein expression was restricted to the bone-forming area in the malignant mesothelioma.

Clinical, neuropathological, and molecular study in two families with spinocerebellar ataxia type 6 (SCA6)

To clarify the clinical, neuropathological, and molecular characteristics of spinocerebellar ataxia type 6 (SCA6), two unrelated Japanese families with SCA6 were studied. A clinical feature of the two families was late onset "pure" cerebellar ataxia. Pathologically, three SCA6 brains consistently showed Purkinje cell dominant cortical cerebellar degeneration. Morphometric analysis showed that loss of the cerebellar granule cells and inferior olivary neurons were very mild compared with the severity of Purkinje cell loss. There was no obvious ubiquitin immunoreactive nuclear inclusions. All affected patients had identical expanded alleles, and the expansion was also homogeneously distributed throughout the brain without mosaicism. The present study showed that SCA6 is characterised by Purkinje cell dominant cortical cerebellar degeneration, highly stable transmission of the CAG repeat expansion, and lack of ubiquitin immunoreactive nuclear inclusions.

Protective effects of pregnancy and lactation against N-methyl-N-nitrosourea-induced mammary carcinomas in female Lewis rats

The role of parity before and after N-methyl-N-nitrosourea (MNU) treatment in protection against mammary carcinogenesis was investigated. The effect of lactation on reduction in the incidence of mammary carcinoma was also examined. Parous rats were compared with respective age-matched virgins (AMVs). Pregnancy and lactation prior to MNU exposure significantly reduced both the incidence of mammary carcinoma (22 versus 72%) and the average number of mammary carcinomas per rat (0.22 versus 0.86) and significantly prolonged the latency of the carcinomas (247 versus 215 days). Pregnancy and lactation following MNU exposure also significantly reduced both the incidence of mammary carcinoma (25 versus 94%) and the average number of mammary carcinomas per rat (0.25 versus 1.50) and significantly prolonged the latency (240 versus 155 days). Lactation showed an additive effect on the reduction in mammary cancer. Pregnancy suppressed the number of estrogen receptor (ER)- and progesterone receptor (PgR)-positive cells and lowered the cell proliferation rate in the non-tumoral mammary glands. Since the majority (>76%) of the mammary carcinomas was hormone dependent in both the parous and AMV rats, pregnancy and lactation appear to decrease the ER- and/or PgR-positive cells presumed to be the progenitors of hormone-dependent carcinomas and they lowered the cell turnover necessary for tumor promotion in parous rats, resulting in a lower mammary carcinoma yield.

In vitro human Th-cell responses to a recombinant hepatitis C virus antigen: failure in IL-2 production despite proliferation

Hepatitis C Virus (HCV) causes chronic infection in 80-90% of those exposed and persists despite evidence of immune recognition. To understand the immunological basis of this phenomenon, we have synthesized a non structural (NS) protein that is critical to HCV infection and replication, NS3, and used it to study in vitro helper T-cell responses from infected individuals. Strong proliferative responses were generated by peripheral T-cells isolated from a subset of chronically infected patients, but not by normal, non-infected controls. Interestingly, though gamma-interferon (gammaIfn) and IL-10 were both secreted in response to stimulation by NS3 antigen, IL-2 was not. In contrast, IL-2 was secreted in response to influenza virus vaccine antigen. Lack of IL-2 induction was confirmed by a failure to amplify IL-2 mRNA upon NS3 antigen stimulation, whereas IL-4, IL-15, and gammaIfn mRNA were seen as early as 24 h. The predominance of IL-4 and IL-10 and the lack of IL-2 suggests that in vitro responses to at least some HCV antigens are biased towards a Th2 phenotype, which may be conducive to viral persistence.

Purification, characterization, and application of an acid urease from Arthrobacter mobilis

It has been shown that urea in fermented beverages and foods can serve as a precursor of ethylcarbamate, a potential carcinogen, and acid urease is an effective agent for removing urea in such products. We describe herein the purification and characterization of a novel acid urease from Arthrobacter mobilis SAM 0752 and show its unique application for the removal of urea from fermented beverages using the Japanese rice wine, sake, as an example. The purified acid urease showed an optimum pH for activity at pH 4.2. The enzyme exhibited an apparent K(m) for urea of 3.0 mM and a Vmax of 2370 mumol of urea per mg and min at 37 degrees C and pH 4.2. Gel permeation chromatographic and sodium dodecyl sulfate gel electrophoretic analyses showed that the enzyme has an apparent native molecular weight (M(r)) of 290,000 and consisted of three types of subunit proteins (M(r), 67,000, 16,600, 14,100) denoted by alpha, beta, and gamma. The most probable stoichiometry of the subunits was estimated to be alpha: beta: gamma = 1:1:1, suggesting the enzyme subunit structure of (alpha beta gamma)3. The enzyme also existed as an aggregated form with an M(r) of 580,000. The purified enzyme contained 2 g-atom of nickel per alpha beta gamma unit of the enzyme. Enzyme activity was inhibited by acetohydroxamic acid, HgCl2, and CuCl2. The isoelectric point of the native enzyme was estimated by gel electrofocusing to be 6.8. Urea (50 ppm), which was exogenously added to sake (pH 4.4, 17 +/- 1% (v/v) ethanol), was completely decomposed by incubation with the enzyme (0.09 U ml-1) at 15 degrees C for 13 days. The enzyme was unstable at temperatures higher than 65 degrees C and pHs lower than 4, and was completely inactivated under the conditions of a pasteurization step involved in the traditional sake-making processes. These results indicate that the enzyme is applicable to the elimination of urea in fermented beverages with minimal modification to the conventional process.

Hepatic arterial infusion chemotherapy of cisplatin for biliary cystadenocarcinoma

Biliary cystadenocarcinoma is a rare tumor which has a better prognosis after complete surgical removal. However, since there is no other effective therapeutic option instead of surgery, the prognosis is very poor if surgical resection is impossible. We report the case of a 78 year-old woman who was treated only by hepatic arterial infusion (HAI) chemotherapy of cisplatin (85 mg) because liver functional reserve was too bad to perform a major hepatectomy. Huge biliary cystadenocarcinoma occupying the right lobe of the liver measuring 12 cm in size before chemotherapy was drastically decreased to 2 cm in size 8 months after chemotherapy. Although she had abdominal pain and anorexia before chemotherapy, she is doing well and has no complaints 9 months after chemotherapy. In conclusion, an effective therapy may be possible using hepatic arterial infusion chemotherapy of cisplatin in patients with biliary cystadenocarcinoma for whom surgical treatment is not suitable.

Study on Parkinson's disease and alcohol drinking

To clarify alcohol drinking habits of patients with Parkinson's disease (PD) in Japanese, we compared mean values of alcohol consumption of PD patients and controls with special references to genetic polymorphism of ALDH2. Ninety-three Japanese outpatients with PD (39 males, 54 females) diagnosed by three skilled neurologists from 4 hospitals in Kanto area were analyzed for ALDH2 genotypes and alcohol consumption. A total of 297 healthy controls (156 males, 141 females) in the same area were also analyzed. PCR- SSCP (polymerase chain reaction-single strand conformational change polymorphism) analysis was used to determine ALDH2 genotypes. Mean values of alcohol consumption (ethanol g/month/person) from patients with PD were estimated by direct interview, and those from controls were obtained by questionnaire. Distributions of three genotypes and allele frequencies of ALDH2 were not different between patients and controls, however mean values of alcohol consumption of PD group were significantly lower than those of control group when compared between the same ALDH2 genotype. Our data suggested that the lower values of alcohol consumption in patients with PD for every ALDH2 genotypes may be caused by other factors such as premorbid personality rather than ALDH2 variant.

Effects of sex steroids and growth factors on invasive activity and 5'-deoxy-5-fluorouridine sensitivity in ovarian adenocarcinoma OMC-3 cells

Effects of sex steroids (estradiol-17 beta, E2; progesterone, Prog) and growth factors (epidermal growth factor, EGF; transforming growth factor-alpha, TGF-alpha) on invasive activity and 5'-deoxy-5-fluorouridine (5'-dFUrd) sensitivity of ovarian adenocarcinoma OMC-3 cells were investigated. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were inhibited by 10 microM Prog, but stimulated by 0.1-10 nM EGF and TGF-alpha in a concentration-dependent manner. E2 did not have any effect on tumor cell migration or invasion. The zymography of tumor conditioned medium showed that the treatment of OMC-3 cells with EGF and TGF-alpha resulted in increases of type IV collagenase, stromelysin and urokinase-type plasminogen activator (uPA). EGF and TGF-alpha up-regulated thymidine phosphorylase (dThdPase) expression of tumor cells and consequently enhanced the antiproliferative action of 5'-dFUrd, which is converted to 5-fluorouracil by dThdPase. E2 and Prog did not have significant effects on the expression of proteolytic enzymes and dThdPase, or on the 5'-dFUrd sensitivity of tumor cells. The inhibitory effect of Prog on tumor cell invasion may depend on its inhibitory action on the motility of tumor cells. These results suggest that EGF and TGF-alpha simultaneously up-regulate the potential of ovarian adenocarcinoma cells to invade extracellular matrices and their dThdPase expression, both of which are associated with the specific action of 5'-dFUrd selectively to kill tumor cells with high invasive and metastatic potential.

Immunohistochemical localization of epithelial glycoprotein EGP-2 and carcinoembryonic antigen in normal colonic mucosa and colorectal tumors

Epithelial glycoprotein EGP-2 and carcinoembryonic antigen (CEA) are transmembrane glycoproteins and cell surface markers. Eighty-four colorectal tumors including 23 adenomas (2 mild, 13 moderate, and 8 severe atypia) and 61 adenocarcinomas (33 well- and 28 moderately differentiated) as well as adjacent normal colonic mucosa (51 cases) were studied for the immunolocalization of EGP-2 as detected by the monoclonal antibody VU-1D9, and compared with CEA expression. In the normal colonic mucosa, basolateral VU-1D9 expression in the surface epithelial cells was constantly seen in all 51 cases, while weak apical CEA staining in the surface epithelium was seen in 25% (13/51) of the cases. In 91% (21/23) of the adenomas, regardless of the grade of atypia, VU-1D9 labeled the basolateral membrane of a few surface lining cells leaving atypically proliferating glands negative, while CEA expressed strong apical staining in the surface epithelial cells as well as atypically proliferating glands. The well-differentiated adenocarcinomas showed homogeneous basolateral staining for VU-1D9 and strong apical staining for CEA; the moderately differentiated adenocarcinomas showed membranous as well as cytoplasmic VU-1D9 staining and luminal as well as cytoplasmic CEA staining. The VU-1D9 and CEA localizations and the stage of expression in relation to tumor progression were completely different. Strong CEA expression was seen in the adenomatous stage, while the homogeneous VU-1D9 expression required tumor progression to the carcinomatous stage. VU-1D9 especially when applied in combination with CEA, will be a useful marker for colorectal lesions, and its reactivity patterns in carcinoma can predict the prognosis.

Study of prediagnostic selenium level in toenails and the risk of advanced prostate cancer

BACKGROUND

In a recent randomized intervention trial, the risk of prostate cancer for men receiving a daily supplement of 200 microg selenium was one third of that for men receiving placebo. By use of a nested case-control design within a prospective study, i.e., the Health Professionals Follow-Up Study, we investigated the association between risk of prostate cancer and prediagnostic level of selenium in toenails, a measure of long-term selenium intake.

METHODS

In 1986, 51,529 male health professionals aged 40-75 years responded to a mailed questionnaire to form the prospective study. In 1987, 33,737 cohort members provided toenail clippings. In 1988, 1990, 1992, and 1994, follow-up questionnaires were mailed. From 1989 through 1994, 181 new cases of advanced prostate cancer were reported. Case and control subjects were matched by age, smoking status, and month of toenail return. Selenium levels were determined by neutron activation. All P values are two-sided.

RESULTS

The selenium level in toenails varied substantially among men, with quintile medians ranging from 0.66 to 1.14 microg/g for control subjects. When matched case-control data were analyzed, higher selenium levels were associated with a reduced risk of advanced prostate cancer (odds ratio [OR] for comparison of highest to lowest quintile = 0.49; 95% confidence interval [CI] = 0.25-0.96; P for trend = .11). After additionally controlling for family history of prostate cancer, body mass index, calcium intake, lycopene intake, saturated fat intake, vasectomy, and geographical region, the OR was 0.35 (95% CI = 0.16-0.78; P for trend = .03).

CONCLUSIONS

Our results support earlier findings that higher selenium intakes may reduce the risk of prostate cancer. Further prospective studies and randomized trials of this relationship should be conducted.

Dysfunction of the hypothalamic-pituitary system in mitochondrial encephalomyopathies

We investigated endocrine function in patients with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), myoclonus epilepsy associated with ragged-red fibers (MERRF), and chronic progressive external ophthalmoplegia (CPEO). Hypothalamic-pituitary function was impaired in all three patients with MELAS or MERRF, but none of four with CPEO. A MELAS patient with dwarfism and impaired adolescent development had decreased growth hormone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH). A MERRF patient had emaciation and low adrenocorticotropin. A patient with mitochondrial encephalomyopathy transitional between MELAS and MERRF showed delayed, blunted LH and FSH response to LH-releasing hormone stimulation. We concluded that patients with mitochondrial encephalomyopathies, especially MELAS or MERRF, are likely to have hypothalamic-pituitary dysfunction.

Clinical application of hepatitis C virus core protein in early diagnosis of acute hepatitis C

A fluorescence enzyme immunoassay (FEIA) for the quantitative measurement of hepatitis C virus (HCV) core protein has recently been developed. In this study, we studied the clinical usefulness of this measurement in patients with acute hepatitis C. Eighteen patients with post-transfusion acute hepatitis C were enrolled in the study; 5 patients showed resolution of hepatitis with disappearance of HCV viremia, while the remaining 13 patients did not. A second generation HCV antibody, HCV RNA, and HCV core protein were measured in serial serum samples taken within 1 month of the onset of acute hepatitis and 3, 6, 12, 24, and 36 months after onset. Within the first month after disease onset, the positivity rates of HCV RNA (100%; P = 0.0014) and HCV core protein (89%; P = 0.0300) were both significantly higher than that of HCV antibody (56%). Six months after disease onset, the positivity rate of HCV antibody had increased, to 100%, and the positivity rates of HCV RNA and HCV core protein began to decrease. HCV core protein levels did not differ between patients with resolved and unresolved disease in the first month after disease onset. These findings indicate that FEIA, a simple assay, for the measurement of HCV core protein was useful for the early diagnosis of acute hepatitis C.

Factors related to axillary lymph node metastasis in T1 breast carcinoma

The current study was performed on 38 cases of T1 breast cancers ( 2 cm in greatest diameter) to identify the factors related to recognition of axillary lymph node (AxLN) metastasis. Ten patients (26.3%) had lymph node metastases. Comparing the AxLN positive (+) group with the AxLN negative (-) group revealed that tumor size and hormone receptor status as well as age of the patients were not significantly different. However, the Ki-67 labeling index (22.2 +/- 5. 9% vs. 12.5 +/- 2.8%), the microvessel count (43.8 +/- 12.4/0.785 mm2 vs. 27.0 +/- 8.4/0.785 mm2) and bcl-2+ cases (70% vs. 29%) were significantly higher in the AxLN+ cases. These results suggest that the Ki-67 labeling index, microvessel count and Bcl-2 expression, especially when combined, are useful predictors of AxLN metastases in T1 breast cancers.