Correlation of the mutation of p53 gene and the polymorphism at codon 72 in smoking-related non-small cell lung cancer patients

The polymorphism of p53 gene at codon 72 consisting of either arginine (Arg)- or proline (Pro)-encoded allele is suggested to be associated with the susceptibility of tobacco-related lung cancer. In this study we examined the polymorphism of 224 non-small cell lung cancer (NSCLC) patients and that of 303 control persons with a polymerase chain reaction method and found that Pro-allele carriers were significantly more frequent in those patients who smoked and were affected at a younger age (<65) (P<0.05). We also investigated whether the mutational alterations of this gene could be influenced by the genotype. The overall mutation rate of 114 NSCLC patients examined with a single-strand conformation polymorphism method was 31%, which agreed with previous reports. However, the mutation rate was significantly increased in those patients who smoked and were affected at a younger age (<65) (P<0.05). Although the Pro-allele carriers among the smoker patients showed higher mutation rate than the Arg/Arg homozygotes, the difference between the genotypes had marginal significance (0.1<P<0.05) and was statistically insignificant, if the study was confined to younger patients. Thus, the present data cannot confirm a possible association of the p53 polymorphism with its mutation rate regarding smoking-related lung cancer.

Characterization of disease resistance gene-like sequences in near-isogenic lines of tomato

We examined near-isogenic lines (NILs) carrying either of the tomato mosaic virus (ToMV) resistance genes Tm-1 and Tm-2 for sequences homologous to the isolated disease-resistance genes. DNA fragments were amplified from the genomic DNA of the NILs by the polymerase chain reaction (PCR) using primers designed on the basis of sequences of certain domains conserved among some disease-resistance genes. Of ten PCR products cloned, five were identified as having homology to either of the two classes of disease-resistance genes. The first class encoded proteins containing leucine-rich repeats (LRRs) and a nucleotide-binding site (NBS), such as the RPS2 gene in Arabidopsis and the N gene in tobacco. The second class encoded proteins containing a C-terminal membrane anchor but no NBS, such as the Cf 2 and Cf 9 genes in tomato. In Southern hybridization of the genomic DNAs of the NILs carrying either Tm-1 or Tm-2 and their parental NIL carrying neither of these resistance genes, multiple bands could be detected with most of the clones used as probes. This suggests that the genomes of the NILs contain multiple copies of sequences homologous to some of the known disease-resistance genes. No evidence was obtained to show that the Tm-1 and/or Tm-2 loci encode either class of protein, since no polymorphic band patterns between the NILs were detected by Southern hybridization.

Foramen magnum syndrome caused by atlanto-occipital assimilation

Atlanto-occipital assimilation is one of the most common congenital anomalies of the craniovertebral junction, and it usually is asymptomatic. We report a case of this malformation with unusual neurological symptoms which correlate with radiological findings. The anomaly caused the so-called foramen magnum syndrome, which was difficult to localize with neurological examination. The patient also had atlanto-axial dislocation, which was thought to enhance the symptoms with change of head/neck position.

Superoxide formation and DNA damage induced by a fragrant furanone in the presence of copper(II)

2,5-Dimethyl-4-hydroxy-3(2H)-furanone (2,5-DMHF), a caramel-like fragrant compound found in may processed foodstuff, has been reported to be mutagenic. 4,5-Dimethyl-3-hydroxy-2(5H)-furanone (4,5-DMHF), which is a similar characteristic fragrant compound, has no report concerning its mutagenicity. DNA damage by 2,5-DMHF and 4,5-DMHF was investigated by using DNA fragments obtained from the p53 tumor suppressor gene. 2,5-DMHF induced DNA damage extensively in the presence of Cu(II), but only slightly in the presence of Fe(III). 4,5-DMHF did not cause metal-dependent DNA damage. Bathocuproine, a Cu(I)-specific chelator, and catalase inhibited DNA damage induced by 2,5-DMHF plus Cu(II), whereas free hydroxyl radical scavengers did not. The order of DNA cleavage sites was thymine, cytosine > guanine residues. The site-specific DNA damage and effects of scavengers show that DNA-copper-oxygen complex rather than free .OH are involved in the DNA damage. Formation of 8-oxodeoxyguanosine (8-oxodG) by 2,5-DMHF increased with its concentration in the presence of Cu(II), whereas 8-oxodG formation increased only slightly in the presence of Fe(III). Degradation of 2,5-DMHF was efficiently accelerated by Cu(II), but only slightly accelerated by Fe(III). The degradation of 4,5-DMHF was little even in the presence of metal ions. Examination using cytochrome c suggest that superoxide was generated from 2,5-DMHF. Stoichiometric study of Cu(II) reduction revealed that autoxidation of 2,5-DMHF could offer 4-electron reduction. These results suggest that, at least in vitro and in an acellular system, 2,5-DMHF generates superoxide and subsequently hydrogen peroxide to induce metal-dependent DNA damage.

Cloning genomic DNA encoding apple polyphenol oxidase and comparison of the gene product in Escherichia coli and in apple

Two PCR-amplified genomic DNA fragments encoding apple (cv. Fuji) polyphenol oxidase (PPO) were cloned and sequenced. A comparison of genomic DNA with cDNAs revealed that the PPOs lacked introns. Both PPO DNAs appear to encode a 66-kDa precursor protein consisting of a 56-kDa mature protein and a N-terminal transit peptide of 10-kDa N-terminal transit peptide. Apple PPO DNA was expressed in Escherichia coli, and the gene product (56 kDa) without a transit peptide was immunochemically detected and was the same size (ca. 65 kDa) as the main PPO of apple fruit by SDS-PAGE.

BMP-induced osteogenesis on the surface of hydroxyapatite with geometrically feasible and nonfeasible structures: topology of osteogenesis

Bone morphogenetic protein (BMP) is known to require a suitable carrier to induce ectopic bone formation in vivo. Hydroxyapatite ceramics have been reported to be effective in some forms but ineffective in others as a carrier of BMP-induced bone formation. In this study we compare three geometrically different forms of hydroxyapatite to examine their functions as carriers of BMP-induced bone formation. A fraction containing all the active BMPs (BMP cocktail) was partially purified from a 4M guanidine extract from bovine bone by a three-step chromatographic procedure. The BMP cocktail was combined with each of three forms of hydroxyapatite--solid particles (SPHAP), porous particles (PPHAP), and coral-replicated porous tablets (coral-HAP)--and implanted subcutaneously into rats. Both the PPHAP and coral-HAP systems induced osteogenesis 2 weeks after implantation, as evidenced by morphological and biochemical observations. Details of the osteogenetic process were followed by double-fluorescence labeling in the coral-HAP system to confirm bone formation on the surface of hydroxyapatite. However, there was no evidence of osteogenesis or chondrogenesis in the SPHAP system. The results indicate that the geometry of the interconnected porous structure in PPHAP and coral-HAP create spaces for vasculature that lead to osteogenesis while the smooth structure and close contact of particles in SPHAP inhibit vascular formation and proliferation of mesenchymal cells, preventing bone and cartilage formation. It was concluded that the geometrical structure in hydroxyapatite ceramics that induces vasculature is crucial as a carrier for BMP-induced bone formation.

Primary structure and functional expression of a novel non-selective cation channel

A non-selective cation channel is believed to play important roles in various tissues. A novel complementary DNA encoding non-selective cation channel was isolated from MIN6, a mouse insulin secreting beta-cell line. This channel (mNSC1) conducts predominantly monovalent cations in Xenopus oocytes and is selective for cations over anions (PK/PCl = 10). The current was completely blocked by lanthanum and niflumate. The mNSC1 of 423 amino acids contains a characteristic leucine repeat and unique membrane topology. The messenger RNA of this channel are abundant in the brain, heart, and lung. We may therefore conclude that studies with this channel will provide important information for understanding physiological functions of the excitable cells as well as non-excitable epithelia.

Presence of follipsin complexed with alpha 2-macroglobulin in porcine ovarian follicular fluid

Using the follicular fluid of porcine ovaries as a source, a high-molecular-weight protein having enzyme activity toward t-butyloxycarbonyl-Gln-Arg-Arg-4-methylcoumaryl-7-amide was purified to an apparent homogeneity. Its molecular weight was estimated to be approximately 720,000. The protein was immunoprecipitated with antihuman alpha 2-macroglobulin antibody and was visualized in Western blot analysis using the same antibody. Using Western blot analysis, an 85 kDa polypeptide, which was recognized by antiporcine follipsin antibodies, was detected in this high-molecular-weight protein. When tested for substrates and inhibitors with low molecular weight, the protein showed substrate specificity and an inhibitor profile similar to those of follipsin. On the basis of these results, it was concluded that the protein is a complex of follipsin with alpha 2-macroglobulin. The complexed enzyme activated a single-chain precursor tissue-type plasminogen activator at a drastically reduced rate compared with free follipsin. The present results suggest that intrafollicular follipsin activity is regulated by the proteinase inhibitor alpha 2-macroglobulin.

Correlation between surface morphology and surface forces of protein A adsorbed on mica

We have investigated the morphology and surface forces of protein A adsorbed on mica surface in the protein solutions of various concentrations. The force-distance curves, measured with a surface force apparatus (SFA), were interpreted in terms of two different regimens: a "large-distance" regimen in which an electrostatic double-layer force dominates, and an "adsorbed layer" regimen in which a force of steric origin dominates. To further clarify the forces of steric origin, the surface morphology of the adsorbed protein layer was investigated with an atomic force microscope (AFM) because the steric repulsive forces are strongly affected by the adsorption mode of protein A molecules on mica. At lower protein concentrations (2 ppm, 10 ppm), protein A molecules were adsorbed "side-on" parallel to the mica surfaces, forming a monolayer of approximately 2.5 nm. AFM images at higher concentrations (30 ppm, 100 ppm) showed protruding structures over the monolayer, which revealed that the adsorbed protein A molecules had one end oriented into the solution, with the remainder of each molecule adsorbed side-on to the mica surface. These extending ends of protein A overlapped each other and formed a "quasi-double layer" over the mica surface. These AFM images proved the existence of a monolayer of protein A molecules at low concentrations and a "quasi-double layer" with occasional protrusions at high concentrations, which were consistent with the adsorption mode observed in the force-distance curves.

Inhibition of maitotoxin-induced Ca2+ influx in rat glioma C6 cells by brevetoxins and synthetic fragments of maitotoxin

45Ca2+ influx in rat glioma C6 cells induced by 0.3 nM maitotoxin (MTX) was markedly inhibited by brevetoxin A (PbTx1) and brevetoxin B (PbTx2), with EC50 values of 16 and 13 microM, respectively. This inhibition was observed immediately after addition of MTX when monitored with fura-2, which suggests that PbTx2 directly blocks the action of MTX. This blockade by PbTx2 was not affected by tetrodotoxin, which excludes the involvement of voltage-sensitive sodium channels. The depolarizing effects of these brevetoxins were also not a likely cause of this inhibition, because melittin, a channel-forming peptide, did not significantly block MTX-induced 45Ca2+ influx. Instead, this inhibition was thought to be mediated by blockade of an MTX-binding site by the brevetoxins, based on the fact that these toxins, particularly PbTx2, closely mimic the partial structure of MTX. Synthetic fragments of MTX corresponding to the hydrophilic EF-GH rings (200 microM) and LM-NO rings (500 microM) of MTX significantly reduced MTX-elicited Ca2+ influx. The observation that the effects of MTX were inhibited by structural mimics of both its hydrophobic and hydrophilic portions implies that both portions of the MTX molecule recognize its target.

Maturation and degradation of beta-galactosidase in the post-Golgi compartment are regulated by cathepsin B and a non-cysteine protease

Lysosomal beta-galactosidase precursor is processed to a mature form and associated with protective protein in lysosomes. In this study we used two cysteine protease proinhibitors, E64-d for cathepsins B, S, H, and L, and CA074Me for cathepsin B. They are converted intracellularly to active forms, E-64c and CA074, respectively. Both active compounds inhibited maturation of the exogenous beta-galactosidase precursor, but E-64c did not inhibit further degradation to an inactive 50-kDa product. We concluded that cathepsin B participated exclusively in maturation of beta-galactosidase, and a non-cysteine protease was involved in further degradation and inactivation of the enzyme molecule.

Effects of chronic levodopa therapy on dopa pharmacokinetics

We reevaluate here the effects of chronic administration of levodopa on its peripheral pharmacokinetics and the contribution of the pharmacokinetics to the pathogenesis of the wearing-off phenomenon. The peak levodopa concentration (Cmax) and the area under the time-concentration curve (AUC) were markedly increased after long-term levodopa therapy, whereas the time to the peak concentration (Tmax) and the elimination half-life (T(1/2)) were decreased. These results suggest that long-term levodopa therapy accelerates the absorption of levodopa. Furthermore, the wearing-off group had a markedly higher Cmax and AUC, and a shorter Tmax and T(1/2) than the stable group. We speculate that the clinical expression of 'stable' or 'wearing-off' depends on the absorption of levodopa as well as the presynaptic terminal and postsynaptic receptors.

A 192Arg variant of the human paraoxonase (HUMPONA) gene polymorphism is associated with an increased risk for coronary artery disease in the Japanese

Recent reports have suggested that polymorphisms in the human paraoxonase (HUMPONA) gene may be a genetic risk factor for coronary artery disease (CAD) in white populations. However, this association has not yet been confirmed in other ethnic populations. We studied 75 Japanese patients with CAD, whose coronary lesions were confirmed by angiography, and 115 Japanese control subjects with no history of CAD and a normal resting electrocardiogram. The assays for genotyping the two polymorphisms in the HUMPONA gene (192Arg/Gln and 55Leu/Met) were based on changes in restriction enzyme digestion patterns. For codon 192, the frequencies of the Arg-coding allele (B allele) in both patients and control subjects were much higher than those from published results of whites (.26 to .31), and the difference between patients (.74) and control subjects (.59) was statistically significant (P = .002). The patient group had a higher proportion of Arg/Arg (B/B) homozygotes (52.0% vs 32.2%, P = .006). For codon 55, the frequencies of the Leu-coding allele in control subjects and patients were much higher (.91 and .93, respectively) than those published results for whites, but there was no difference between Japanese control subjects and Japanese patients. When subjects with the 55Leu/Leu genotype only were analyzed, 192Arg/Arg homozygotes were still significantly more frequent in the patients than in the control subjects (55.4% vs 37.2%, P = .024), and the frequency of the 192Arg allele was also higher in patients than control subjects (P = .013). Logistic regression analysis including conventional coronary risk factors revealed that 192Arg is an independent risk factor for CAD. Thus, in the Japanese, the association of CAD with the 192Arg variant of HUMPONA (B-type enzyme) is similar to that reported for whites, although the allele frequencies for 192Arg and 55Leu are much higher in the former than the latter population.

[Relationship between subjective cognition and observed life-style in nursing students]

Complex interactions between long-standing lifestyles and genetic factors are strongly involved in the pathologenesis of adult diseases or chronic degenerative diseases. We usually use a questionnaire to obtain life-style information from subjects in a health survey. However, the response to questionnaires is a subjective recognition, therefore, it does not always precisely correspond to the actual situation. The purpose of this research is to compare the response to the questionnaire about life-styles with facts that can be objectively observed. Furthermore, each aspect of life-styles was examined on a mutual influence grade. The subjects were ninety-eight nursing college students aged from 18 to 23 years old, in good health. Subjective symptoms and daily life practices were investigated by a 15-item questionnaire, as the first step. Therefore, we asked them to record their behavior on a time chart, everyday for ten days. Seven days of serial records were obtained from sixty-four subjects (65.3% of 98 persons). 1) The response "yes" to the questionnaire "Do you sleep well?" and "Do you fall asleep, easily?" was influenced by the hours of sleep, rather than what time the subjects "go-to-bed" or "get-up". The response to "Do you wake up often during the night?" expressed an actual situation, well. 2) For subjective cognition regarding excretion, the answer for "constipation" was associated with the number of defecation per week, though the answer for "diarrhea" was not. 3) The answer to "Do you eat breakfast?" reflected the actual situation. However, the answer for "Do you eat between meals?" did not express the actual situation, that is, even the subjects who answered "occasionally" or "I don't eat between meals" had eaten between meals 6.1 times per week, on average. 4) There were mutual influences among sleeping, eating breakfast and excretion.

[Traditional remedy-induced Chinese herbs nephropathy showing rapid deterioration of renal function]

A 19-year-old female was referred to our hospital for azotemia and anemia. She had been taking a health food for atopic dermatitis for about three years. Urinalysis showed proteinuria, glycosuria and microscopic hematuria. Generalized aminoaciduria was observed. Moreover, severe anemia, azotemia, hypokalemia and hypophosphatemia were also observed. Renal biopsy specimen disclosed hypocellular interstitial fibrosis and degeneration of the proximal tubular epithelial cells. No remarkable changes were observed in the glomeruli. Aristolochic acid was detected in the health food. From these findings, she was diagnosed as having Chinese herbs nephropathy (CHN). Although consumption of the food intake was stopped, her renal function deteriorated rapidly. Previously, we reported that certain kinds of Chinese herbal drugs contain aristolochic acid and that the drugs should be prohibited if aristolochic acid is identified. However, we experienced a patient of CHN arising from traditional remedy, which was not proved to be safe. It should be awared that health foods may contain aristolochic acid.

Present characteristics of symptomatic amebiasis due to Entamoeba histolytica in the east-southeast area of Tokyo

Admitted medical records, from January 1988 to December 1995, of 28 symptomatic amebic patients who lived in the east-southeast area of Tokyo were studied retrospectively, in order to find the present characteristics of symptomatic amebiasis due to Entamoeba histolytica in this area. Categorized by disease, there were 14 cases of colitis, 9 cases of liver abscess, 4 cases of colitis with liver abscess, and 1 case of liver abscess with brain abscess. Patients consisted of 26 Japanese males, 0 Japanese females, 1 non-Japanese male and 1 non-Japanese female. The mean age of colitis patients and liver abscess patients was 55.4 years old and 41.3 years old, respectively. The presumed place of contraction was Japan in 64% of the patients. Forty-eight percent of male patients indicated that they engaged in homosexual or bisexual practices, and 36% of male patients who denied such sexual practices or did not answer the question had no history of marriage. Positive rate of serum titre for Treponema pallidum hemagglutination test (TPHA) and human immunodeficiency virus antibody was 42.9% and 0%, respectively. Sixty-seven percent of TPHA-positive patients indicated that they engaged in male homosexual or bisexual practices. Zymodeme patterns of E. histolytica isolated from 4 colitis patients were XIV in 1 case and II in 3 cases. Symptomatic amebiasis in the east-southeast area of Tokyo is a disease which predominantly afflicts males, especially those in their middle age, and most patients contract the disease in Japan. The high rates of patients who engaged in male homosexual or bisexual practices and the high rates of patients with positive TPHA suggest that amebiasis is likely to be sexually transmitted disease in homosexual and bisexual men in the east-southeast area of Tokyo, and zymodeme II may be the predominant type in symptomatic amebic colitis in this area.

Coronary artery disease and polymorphisms in a receptor mediating shear stress-dependent platelet activation

BACKGROUND

Platelets play pivotal roles in coronary thrombosis, and antiplatelet therapies are widely used for coronary artery disease (CAD). However, the effects of genetic variation in platelets on CAD are poorly understood. We have assessed the association between CAD and polymorphisms in a platelet receptor for von Willebrand factor, the glycoprotein (GP) Ib/IX complex, which mediates shear stress-dependent platelet activation.

METHODS AND RESULTS

Genotypes of the alpha-chain of the receptor (GP Ib alpha, 145Thr/Met) were determined in 91 patients with myocardial infarction (MI) or angina pectoris whose lesions were confirmed by coronary angiography as well as in 105 individuals from the general population with no history of angina or other heart diseases and normal resting ECGs. There was no homozygote for Met/Met in either the control or patient groups. The prevalence of the Thr/Met genotype (T/M) in all patients was not significantly different from that in the control group. However, the frequency of T/M was significantly higher in patients aged < or = 60 years (31.8%) than in control subjects aged < or = 60 years (16.0%; P<.05, odds ratio=2.5). An association was also demonstrated between CAD and the other polymorphism of GP Ib alpha, a variable number of tandem repeats of a 13-amino acid sequence, which is known to be linked to the 145Thr/Met polymorphism. There was an association between the frequency of the T/M genotype and the angiographic severity of CAD: 11.1% for Gensini score < 40 versus 50.0% for Gensini score > or = 40 (P=.0015). There was no difference in the distribution of GP Ib alpha genotypes between patients with MI and those with angina pectoris.

CONCLUSIONS

This study suggests that the presence of the Met allele in GP Ib alpha is a risk factor for the prevalence and severity of CAD in individuals aged < or = 60 years. The results need to be confirmed in a large-scale study of incident case subjects and matching control subjects.

Expression and localization of angiotensin II type 1 receptor mRNA in rat ocular tissues

Angiotensin II type 1 receptor (AT1) is expressed in a variety of tissues. However, the localization of the specific AT1 mRNA in several ocular tissues has not been fully elucidated. In the present study, we investigated the expression and distribution of AT1 mRNA in the several ocular tissues of Wistar-Kyoto rats (WKYs) using the technique of reverse transcription with polymerase chain reaction. The 5 cornea, sclera, iris, ciliary body, and choroid samples tested were negative. When we analyzed 5 retina samples, 4 were positive. AT1 mRNA was more significantly expressed in the retina of WKYs than in the other ocular tissues of WKYs (p = 0.0238 < 0.05). Our study provides the first direct evidence that the AT1 is abundantly present in the WKY retina portions. This is a strategic location for an ocular renin-angiotensin system to influence retinal cicrulation.

Ala601-Thr type dysplasminogenaemia genetically diagnosed in patients with retinochoroidal vascular disorders

Dysplasminogenaemia has been reported in patients with retinochoroidal vascular disorders. The precise genetic defects of these cases, however, remain unclear because of the limitations of conventional diagnostic techniques. In this study, three patients with these diseases were investigated at the DNA level for the first time to define the molecular bases of these disorders. Polymerase chain reaction-restriction fragment length polymorphism analysis revealed that all three cases carried the same Ala601-Thr mutation. This defect may also play a role in the pathogenesis of circulation disorders in small local vessels because of reduced fibrinolytic activity due to decreased functional plasminogen levels.

Heart rate variability during 24 hours in asthmatic children

The autonomic circadian rhythm plays an important role in asthma. In recent years it has become possible to evaluate autonomic nervous function (ANF) using analysis of heart rate variability (HRV). We analyzed the HRV in the 24h period following the state without an asthma attack in order to study the relationship between asthma and ANF. The HRV was analyzed in 94 asthmatic children (ages 5-15 years). These subjects were divided into groups according to the severity of their asthma. After recording a 24h ambulatory electrocardiograph (AECG), the HRV was analyzed by a computer. Evaluation of the HRV was carried out using time-domain and frequency-domain analyses. The ANF of asthma subjects was decreased in comparison to the normal group. The severity of asthma had a significant effect on the %RR50 (the proportion of cycles during which the difference is > 50 ms), the SD (standard deviation; mean of standard deviation of all normal RR intervals for all 5-minute periods), the low-frequency (LF) band (0.04 to 0.15 Hz), and the high-frequency (HF) band (0.15 to 0.4 Hz) (%RR50: F = 4.31, p = 0.01; SD: F = 3.48, p = 0.03; LF: F = 3.67, p = 0.02; HF: F = 3.41, p = 0.03). These values were lowest in the severe asthma group. With regard to the therapy grouping, the index that exhibited a significant difference was the NNA (mean of normal-to-normal RR intervals over 24h) (F = 4.43, p = 0.01). In conclusion, even in the normal condition in which the patient is free of an asthma attack, the ANF of asthma sufferers differs from that of normal children. It is possible that the different ANF of asthma sufferers is related to the severity of the asthma.