Localization of a gene for Fukuyama type congenital muscular dystrophy to chromosome 9q31-33.

Fukuyama type congenital muscular dystrophy (FCMD) is an autosomal recessive severe muscular dystrophy associated with an anomaly of the brain. Twenty-one FCMD families, 13 of them with consanguineous marriages, were analysed by genetic linkage analyses with polymorphic microsatellite markers to map the FCMD gene. Significant lod scores were obtained with the markers D9S58 (Zmax = 5.81 at theta = 0.06), D9S59 (Zmax = 4.33 at theta = 0.02), and HXB (Zmax = 3.28 at theta = 0.09) on chromosome 9q31-33. Multipoint analysis placed FCMD between D9S58 and D9S59, with a maximum lod score of 16.93. These markers will be useful for presymptomatic, prenatal and carrier diagnosis of family members carrying FCMD, and they represent important resources for the identification of a gene responsible for FCMD.

Enhancement of lysolecithin acyltransferase activity by LDL in thrombin-stimulated porcine-cultured endothelial cells.

Changes of intracellular activity of lysolecithin acyltransferase (LAT) during an interaction between endothelial cells (EC) and low-density lipoprotein (LDL) were investigated. Following an incubation of EC with LDL, endothelial LAT activity was assayed using [3H]lysophosphatidylcholine as the substrate. Stimulation of EC with either thrombin (0.01-1 U/ml) or Ca(2+)-ionophore A23187 (10(-10)-10(-7) M) dose- and time-dependently enhanced LAT activity in the presence of LDL (1 mg protein/ml), but no enhancement was observed in quiescent cells. Ionomycin together with 1-oleoyl-2-acetyl glycerol, a synthetic analog of diacylglycerols enhanced LAT activity in a similar degree to thrombin in the presence of LDL. Either staurosporine, a protein kinase C inhibitor or neomycin, a phospholipase C inhibitor completely blocked an increase of LAT activity in stimulated EC. Stimulation of EC with various agonists including 12-o-tetradecanoylphorbol-13-acetate, an activator of protein kinase C caused a marked increase in cellular uptake of LDL, and staurosporine inhibited the uptake. These results suggest that the transport of LDL into EC is facilitated by stimulation with thrombin and other agonists, and LDL subsequently activates intracellular LAT. Protein kinase C seems to mediate LDL uptake into EC. Intracellular regulatory roles of LDL in the presence of vasoactive substances were discussed.

Caseins are cross-linked through their ester phosphate groups by colloidal calcium phosphate.

Artificial casein micelles were prepared by adding 30 mM calcium, 22 mM phosphate and 10 mM citrate to sodium caseinate solutions, and the content of the casein aggregates cross-linked by colloidal calcium phosphate was determined by high-performance gel chromatography on a TSK-GEL G4000SW column in the presence of 6 M urea. The content of the casein aggregates cross-linked by colloidal calcium phosphate in artificial whole casein micelles was 48% of total casein, and their relative casein composition determined by high-performance ion-exchange chromatography was 53.1% for alpha s1-casein, 15.8% for alpha s2-casein, 31.1% for beta-casein and 0% for kappa-casein. The order of cross-linking by colloidal calcium phosphate agreed with that of the ester phosphate content of casein constituents. The content of the casein aggregates cross-linked by colloidal calcium phosphate was higher in alpha s1-kappa-casein micelles than in beta-kappa-casein micelles. kappa- and gamma-caseins and dephosphorylated alpha s1-casein were not cross-linked by colloidal calcium phosphate. Although kappa-casein was not cross-linked, chemically phosphorylated kappa-casein, of which the average phosphate content was 8.5 per molecule, was cross-linked. It is concluded that caseins are cross-linked through their ester phosphate groups by colloidal calcium phosphate.

Inhibition of cholesterylester accumulation by 17 beta-estradiol in macrophages through activation of neutral cholesterol esterase.

Premenopausal women are at a lower risk of coronary heart disease relative to age matched men. However, the underlying mechanisms are not clearly understood. This article studies the effects of 17 beta-estradiol (17 beta-E2) at physiological concentrations on the cholesterylester metabolism in macrophages (J774 A.1 cells) with a particular focus on neutral cholesterol esterase (N-CEase). Cells were incubated with beta-VLDL, [1-14C]oleic acid and 17 beta-E2 (0.25 and 2.5 nM). 17 beta-E2 dose-dependently reduced cholesteryl-[1-14C]oleate (14C-CO) at 36 h and 48 h relative to the control. It also stimulated hydrolysis of 14C-CO in foam cells on 36 h and 48 h incubation. In addition, 17 beta-E2 markedly increased N-CEase activity at 24 h and 36 h. This increase preceded the enhanced hydrolysis of cholesterylester, 17 alpha-E2 (inactive isomer), estrone and estriol had no stimulatory action on N-CEase, whereas progesterone and testosterone inhibited it. 17 beta-E2-treatment (24 h) increased the activity of cyclic AMP-dependent protein kinase (A-kinase). DEAE-cellulose column chromatography revealed that an isoform (type II) of A-kinase appeared in 17 beta-E2-treated cells in addition to type I of A-kinase found in the control cells. These results suggest that inhibition of cholesterylester accumulation in macrophages by 17 beta-E2 is mediated by an enhancement of N-CEase activity possibly through an increase in A-kinase.

Phase II study of irinotecan, leucovorin, 5-fluorouracil and tegafur/uracil for metastatic colorectal cancer.

Irinotecan combined with continuous-infusion 5-fluorouracil (5FU) has been shown to be an effective and tolerable regimen in the treatment of metastatic colorectal cancer (MCRC). Tegafur/uracil (UFT) during 5FU infusion enhances plasma 5FU concentration, mimics continuous 5FU infusion and delivers the drug to target tumor cells. We conducted a phase II trial of four-agent combined therapy for MCRC, giving patients (pts) intravenous irinotecan (30 mg/m2 on day 1), leucovorin (LV, 200 mg/m2 on day 1 and 2), 5FU (300 mg/m2 on day 1 and 2), and UFT (400 mg/day for 14 days). The main endpoint was the objective tumor response rate. Sixteen pts with a good performance status were enrolled from February 2001 to May 2002. The response rate was 19% (3 partial responses), and 13 pts had stable disease. The median time to progression was 5.2 months, and the median survival time was 20.2 months. Considering the low toxicity and reasonable cost, this regimen deserves further investigation.

Environment: peculiar pigment cell neoplasm in fish.

Chromatophoroma in the croaker (Nibea mitsukurii) showed a unique geographic distribution. The contribution of environmental chemicals to the cause of chromatophoroma in the feral croaker is considered likely on the basis of the following results in our studies. 1) Chromatophoroma was induced in tank-reared N. mitsukurii by administration of certain kinds of known carcinogens such as 7,12-dimethyl-benz(a)anthracene, N-methyl-N'-nitro-N-nitrosoguanidine, and nifurpirinol. 2) Local accumulation of pigment-cell hyperplasia in the catfish (Protosus anguillaris) showed similar tendencies to those of chromatophoroma in N. mitsukurii. 3) Removal of contaminated sediment from the harbor and the river appeared to reduce the incidence from 47% in 1973-1983 to about 20% in 1985-1987. 4) Waste water from a factory located at the station where the incidence of the neoplasm was the highest contained mutagenic substances such as chloroacetones and glyoxals [5]. Exposure of catfish to the waste water induced pigment-cell hyperplasia on the skin.

Lewy body-type degeneration in cardiac plexus in Parkinson's and incidental Lewy body diseases.

Heart tissues of patients with PD or incidental Lewy body (LB) disease (ILBD) were examined by light and electron microscopy. LBs and alpha-synuclein-positive neurites were identified in the hearts from 9 of 11 patients with PD and from 7 of 7 patients with ILBD. LBs were present in both tyrosine hydroxylase-positive and -negative nerve processes, which are nerves of extrinsic sympathetic and intrinsic origin, respectively. These findings provide histologic evidence that the postganglionic sympathetic and intrinsic neurons in the heart are involved in the PD disease process.

The beneficial effect of dibutyryl cyclic adenosine monophosphate on warm ischemic injury of the rat liver induced by cardiac arrest.

Dibutyryl cAMP (DBcAMP) has a high membrane permeability, and maintenance of the intracellular cAMP concentration may improve the viability of organs. In this study, the effect of DBcAMP pretreatment on warm ischemic injury of rat livers was evaluated. Warm ischemic liver injury was induced in adult Wistar rats weighing 250-280 g by leaving them at room temperature (22-25 degrees C) after cardiac arrest. The hepatic cAMP concentration, %ATP, and trypan blue-positive nuclear ratio were determined after different durations of warm ischemia. In addition, transaminase and endothelin-1 (ET-1) release into the perfusate were examined during 60 min of isolated liver perfusion with Krebs-Henseleit solution. The optimal dose and time of DBcAMP pretreatment were determined to be 15 mg/kg and 60 min prior to warm ischemia, respectively. Data on the trypan blue-positive nuclear ratio and the release of transaminases and ET-1 revealed that warm ischemia first damaged the endothelial cells and then the hepatocytes. DBcAMP pretreatment appeared to protect the liver from warm ischemic injury by increasing the intracellular cAMP concentration and stabilizing the cell membranes of endothelial cells and hepatocytes.

Loss of 123I-MIBG uptake by the heart in Parkinson's disease: assessment of cardiac sympathetic denervation and diagnostic value.

UNLABELLED: Myocardial imaging with 123I-metaiodobenzylguanidine (MIBG) was performed on 35 patients with Parkinson's disease and 24 control subjects to evaluate cardiac sympathetic function in patients with Parkinson's disease, verify this phenomenon and examine whether myocardial MIBG uptake and clearance are correlated with the clinical severity of Parkinson's disease. METHODS: We studied 35 patients with Parkinson's disease and 24 control subjects with other central nervous system diseases. The latter group consisted of 12 subjects with other neurodegenerative disorders (4 with spinocerebellar degeneration, 2 with amyotrophic lateral sclerosis, 3 with progressive supranuclear palsy and 3 with corticobasal degeneration and 12 patients with cerebral infarction (CI), 6 with vascular parkinsonism and 6 without it. Early and delayed images of the anterior view were obtained 15 min and 4 h after injection of 123I-MIBG, respectively. MIBG uptake was quantified by calculating a heart-to-mediastinum count (H/M) ratio. RESULTS: The H/M ratio was markedly reduced in the patients with Parkinson's disease (II to V on the Hoehn and Yahr scale) compared with the control subjects. None of the subjects with neurodegenerative diseases showed a marked decrease in myocardial MIBG uptake nor did any subject with CI. CONCLUSION: Our findings indicate that, in Parkinson's disease, a reduction in myocardial MIBG uptake is a very common, specific phenomenon that can be used to detect cardiac autonomic dysfunction to diagnose Parkinson's disease, particularly in patients without typical signs and symptoms.

Fetotoxic effects of mono-2-ethylhexyl phthalate (MEHP) in mice.

Mono(2-ethylhexyl) phthalate (MEHP), one of the main metabolites of di(2-ethylhexyl) phthalate (DEHP), exerted embryo/fetotoxic effects similar to those of DEHP at lower doses. Oral administration of MEHP (1 mL/kg) to the mice of 8 days gestation resulted in less than 32% of live fetuses, all of which were deformed. When DEHP (10 mL/kg) was given to the pregnant mice of 8 days gestation, approximately 0.03% and 0.003% of the administered dose was found in fetuses as DEHP and MEHP, respectively, after 12 hr. The presence of the MEHP in fetuses is probably due to the transplacental crossing of the MEHP formed in the maternal body, since the fetuses of mice up to day 9 of pregnancy showed no hydrolytic activity of DEHP to MEHP. Crossing of MEHP through the placenta was proven by an experiment in which MEHP was administered in pregnant mice. A single injection of MEHP (25 or 50 mg/kg), but not DEHP (500 mg/kg) into pregnant mice, induced a significantly high incidence of somatic mutations in the coat hair of offspring of mice (KYG, female X PW, male; C57BL/6Crj, female X PW, male). All these data suggest that MEHP could be responsible for the embryotoxic/fetotoxic effects observed with DEHP.

Mutagenic/carcinogenic potential of DEHP and MEHP.

The mutagenic/carcinogenic activities of DEHP and MEHP were studied in bacteria and mammalian cells. MEHP but not DEHP exerted a dose-dependent DNA damaging effect to B. subtilis in Rec-assay. DEHP and MEHP showed mutagenic activities to S. typhimurium TA-100, with and without S-9 mix, respectively. MEHP produced not only the mutation in E. coli WP2B/r but also sister chromatid exchanges (SCE) in Chinese hamster V79 cells. It also induced 8AG/6TG-resistant gene mutations and chromosomal aberrations in the V79 cells. Transplacental administration of DEHP or MEHP to the Syrian golden hamster embryos was carried out by administering DEHP or MEHP to gravid animals on day 11 of gestation, followed by the cultivation of embryonic cells for 15-20 days. Both DEHP and MEHP induced 8AG/6TG-resistant mutation, chromosomal aberrations and morphological transformation in the embryonic cells of the Syrian golden hamster.

Teratogenicity/fetotoxicity of DEHP in mice.

The embryonic/fetotoxic effects of DEHP on pregnant mice (ddY-Slc female x CBA male) were studied. DEHP was administered orally in dosages of 0.05 ml/kg to 30.0 mg/kg on day 6, 7, 8, 9 or 10 of gestation. A single administration of DEHP over 0.1 ml/kg (1/300 of LD50) on day 7 of gestation decreased the numbers and the body weight of living fetuses, whereas no significant changes in the numbers of living fetuses (with no gross and skeletal abnormalities) were observed compared with those of the control group, when 0.05 ml/kg (1/600 of LD50) of DEHP was administered. The fetotoxicity (fetal death) was dose dependent. The LD50 and the nonfetolethal maximum dosage of DEHP in its single, oral administration was 592 mg/kg and 64 mg/kg, respectively. The latter value is much higher than an estimated DEHP intake from commercial foodstuffs in men, which is approximately 0.03 mg/kg/day.

Increases in 4-hydroxynonenal and hexanal in bone marrow of rats subjected to total body X-ray irradiation: association with antioxidant vitamins.

Radiation-induced lipid peroxidation and its association with antioxidant vitamins in the bone marrow (BM), of rats subjected to total body irradiation (TBI) of X-rays at a dose of 3 Gy was investigated. The concentration of vitamin C in the BM decreased at 4 h, and reached about 2% of the control level at 24 h after irradiation. The concentration of vitamin E in the BM also decreased to 43% at 24 h. Corresponding to the decrease in vitamin E concentration, the concentration of 4-hydroxynonenal (HNE) in the BM increased 2.5-fold at 24 h. Similarly, increases in the concentrations of hexanal and thiobarbituric acid-reactive substances (TBA-RS) were detected in the BM. In the plasma, these parameters of lipid peroxidation were unchanged up to 48 h, but were increased at 96 h after irradiation. Four days of vitamin E administration to rats (p.o. 460 mg/kg body weight) prior to the 3 Gy X-irradiation increased the vitamin E concentration in the BM to 1.3-fold the control level, but did not attenuate the increases in HNE and hexanal in the BM. The slight accumulation of vitamin E in the BM as a result of the vitamin E treatment may be partly related to this lack of vitamin E effect.

The regulation of cholesteryl ester metabolism by 17 beta-estradiol in macrophages. Activation of neutral cholesterol esterase.

The mechanism for antiatherogenic effects of 17 beta-estradiol (E2) was investigated in J774 A.1 cells incubated with beta-VLDL. E2 at physiological concentrations (0.25 and 2.5 nM) inhibited an accumulation of cellular cholesteryl esters and enhanced their hydrolysis in foam cells. These phenomena were preceded by activation of neutral cholesterol esterase through an increase in cyclic AMP-dependent protein kinase activity. 17 alpha-estradiol, progesterone, and testosterone lacked such stimulatory effects on neutral cholesteryl esterase.

Mutation of low affinity nerve growth factor receptor gene in spontaneously hypertensive and stroke-prone spontaneously hypertensive rats: one of the promising candidate genes for hypertension.

There is evidence that abnormal formation of the sympathetic nervous system might be important for pathogenesis of hypertension. In the present study we analyzed nucleotide sequences of low affinity nerve growth factor receptor (LNGFR) genes in the spontaneously hypertensive rat and its stroke-prone substrain. There was a point mutation generating an amino acid substitution in signal peptide of these LNGFRs. This result suggested that the mutated LNGFR gene is one of the promising candidate genes for hypertension.

Mutation of low affinity nerve growth factor receptor gene is associated with the hypertensive phenotype in spontaneously hypertensive inbred rat strains.

We previously reported a missense mutation in the low affinity nerve growth factor receptor (LNGFR) gene of spontaneously hypertensive rats (SHR), proposing this gene as a promising candidate in genetic hypertension. In this study we provide further support for implicating this gene in genetic hypertension using two new inbred strains, WKHT and WKHA rats. These strains originated from crossbreeding SHR rats with normotensive Wistar-Kyoto rats (WKY): WKHT rats are hypertensive but not hyperactive, and WKHA rats are hyperactive but not hypertensive. Nucleotide sequence analysis of the LNGFR gene revealed that WKHT has the same mutation as SHR, whereas WKHA has the normal sequence, as seen in WKY. These results support our original hypothesis that the mutated LNGFR gene is linked to hypertension, since the mutation had co-segregated with the hypertensive trait, and not hyperactivity trait of SHR.

Reduced functions of intracellular Ca2+ in aggregation, secretion and protein phosphorylation of permeabilized platelets from stroke-prone spontaneously hypertensive rats.

Aggregation, secretion and 47kDa protein (P47) phosphorylation by various agonists such as thrombin, ADP and ionophore A23187 were markedly reduced in platelets from stroke-prone spontaneously hypertensive rats (SHRSP) compared with those of age-matched Wistar Kyoto rat (WKY) platelets, suggesting defective functions of intracellular Ca2+ in SHRSP platelets (Tomita et al. Hypertension 1989; 14: 304-315). To clarify the mechanism of the platelet hypofunctions, saponin permeabilized platelets were prepared to compare the responses of platelets from both rats in varying concentrations of extracellular Ca2+. The leakage of lactate dehydrogenase from saponin (15 micrograms/ml)-treated platelets was approx. 5% of total activity; the degree of the leakage in both platelets did not differ. In saponin-treated platelets, extracellular Ca2+ alone did not induce either aggregation or secretion in both strains. However, in the presence of 1-oleoyl-2-acetylglycerol (10 micrograms/ml), Ca2+ dose dependently stimulated both aggregation and secretion. Under this condition, Ca2+ sensitivity of aggregation, secretion and P47 phosphorylation in SHRSP platelets were significantly reduced compared with those in WKY platelets. These results strongly suggest that intracellular Ca2+ functions are impaired in SHRSP platelets.

The differences in Ca(2+)-sensitivity of protein kinase C in platelets from Wistar Kyoto rat and stroke-prone spontaneously hypertensive rat.

Thrombin-induced phosphorylation of 47 kDa protein (P47) in platelets, a substrate of protein kinase C (PKC), was defective in stroke-prone spontaneously hypertensive rats (SHRSP) (Hypertens. 14, 304-315, 1989). Platelet PKC from SHRSP and Wistar Kyoto rats (WKY) was partially purified and Ca(2+)-sensitivity of PKC activity was examined to understand the defect in the protein phosphorylation. When the platelets from SHRSP and WKY were homogenized in a buffer containing 10 mM EGTA and 2 mM EDTA, approx. 80% of PKC was in the cytosol fraction. PKC in this fraction was purified by DE52 and hydroxyapatite column chromatography. Both platelet PKC preparations contained only PKC-alpha, and there was no significant difference in the Ca(2+)-dependency of activity between them. When the platelets from SHRSP and WKY were homogenized in a buffer containing 10 microM CaCl2, 90% of PKC was found to be bound to the membrane. PKC was extracted from the membrane with a buffer containing 2.5 mM EGTA and 2.5 mM EDTA, and purified by DE52 column chromatography. PKC from WKY platelets eluted as a single peak whereas that from SHRSP platelets eluted as two peaks (peak 1 and peak 2). Ca(2+)-sensitivity of peak 1 PKC was much lower than that of WKY PKC. In contrast, the Ca(2+)-sensitivity of peak 2 PKC appeared to be slightly higher than that of WKY PKC. The specific activity of peak 2 PKC was 4% to 5% of that of peak 1 and WKY PKC. These results suggest that there are two different types of PKC, normal and low Ca(2+)-sensitive in SHRSP platelets. Defective P47 phosphorylation in SHRSP platelets might be attributable to the occurrence of this low Ca(2+)-sensitive PKC.

Congenital changes of platelet functions in stroke-prone SHR: aggregability of gel-filtered platelets, PRP and whole blood, and effects of hypotensive treatment.

Platelet aggregation in whole blood, platelet rich plasma, and gel-filtered platelets were markedly attenuated in SHRSP compared with those in age-matched normotensive WKY. The result was consistent with the previous report of washed platelets. Despite prevention of high blood pressure, a long duration of hypotensive treatment only slightly improved aggregability of washed platelets but did not restore it to the range of age-matched WKY platelets. Blood pressure, heart ratios and thrombin-induced washed platelet aggregation were examined in SHRSP, WKY, and the cross (F1: WKY x SHRSP). The higher blood pressure and heart ratios the lower platelet aggregability was observed in the three strains, and there was no overlapping distribution of these values. F1 progeny exhibited intermediate values in blood pressure, heart ratio and platelet aggregability between the parental values. These results suggested that hypofunctions of SHRSP platelet were not secondary changes due to high blood pressure, but primary changes which are genetically linked to high blood pressure.

Green tea polyphenols (flavan 3-ols) prevent oxidative modification of low density lipoproteins: an ex vivo study in humans.

Oxidation of low density lipoprotein (LDL) plays crucial roles in atherogenesis. We previously reported that green tea polyphenols (flavan 3-ols), especially epigallocatechingallate (EGCg) and epicatechingallate, exerted potent inhibitory effects on LDL oxidation in vitro. To examine whether intake of green tea polyphenols renders LDL resistant to ex vivo oxidation in humans, 22 male volunteers aged between 22 and 32 years were recruited and assigned the same dietary regimen for 2 weeks. After a 1-week baseline period, they were equally divided into two groups: control and tea. The tea group ingested 300 mg of green tea polyphenol extract twice daily for 1 week. Plasma EGCg concentration at the end of the experiment was 56 nmol/L on average (56% in free form) in the tea group; no EGCg was detected before the experiment. Plasma concentrations of lipids, ascorbate, alpha-tocopherol, and lipid peroxides did not change before and after the experiment in either group, but beta-carotene was higher in the tea group (P< 0.01 by paired Student'st-test). LDL (0.1 mg/mL) was incubated with 5 microM Cu(2+) and the oxidation was measured by absorbance at 234 nm. The lag time was significantly prolonged by 13.7 min in the tea group (P < 0.05 by paired Student'st-test, before versus after), whereas such a change was not observed in the control group. These results suggest that daily consumption of seven to eight cups (approximately 100 mL each cup) of green tea may increase resistance of LDL to in vivo oxidation, leading to reduction in the risk of cardiovascular diseases.