Molecular cloning, differential expression, and chromosomal localization of human frizzled-1, frizzled-2, and frizzled-7

cDNAs for three human Wnt receptors, Frizzled-1 (FZD1), Frizzled-2 (FZD2), and Frizzled-7 (FZD7), have now been cloned and characterized. The FZD1, FZD2, and FZD7 genes encode the 647-, 565-, and 574-amino-acid proteins, respectively. FZD1, FZD2, and FZD7 share a common structure consisting of seven transmembrane domains, a cysteine-rich domain in the N-terminal extracellular region, and the C-terminal Ser/Thr-Xxx-Val motif. Relatively large amounts of FZD 1 mRNA, 4.5 kb in size, were detected in adult heart, placenta, lung, kidney, pancreas, prostate, and ovary and in fetal lung and kidney. FZD2 mRNAs 4.0 and 2.4 kb in size were detected in adult heart, fetal brain, lung, and kidney. The level of FZD7 mRNAs 5.0 and 4.0 kb in size was high in adult skeletal muscle and fetal kidney, followed by fetal lung, adult heart, brain, and placenta. The FZD1 and FZD7 genes have been mapped to human chromosome 7q21 and 2q33, respectively.

Cardiac angiotensin II receptors are upregulated by long-term inhibition of nitric oxide synthesis in rats

It has been shown that nitric oxide (NO) may regulate angiotensin II (Ang II) receptors in vitro. To determine whether the chronic inhibition of NO synthesis upregulates cardiac Ang II receptors in a rat model, we evaluated the in vivo effect of Nomega-nitro-L-arginine methyl ester (L-NAME) on several Ang II receptors and on the expression of AT1 receptor mRNA in heart tissue. The chronic administration of L-NAME to normal rats increased the arterial blood pressure. The number of AT1 and AT2 receptors was increased, with no change in affinity, during the first week of L-NAME administration but returned to control levels after 4 weeks of treatment. The AT1 receptor mRNA was changed parallel to AT1 receptor number. Inflammatory changes (monocyte infiltration and myofibroblast formation) in perivascular areas surrounding coronary vessels and myocardial interstitial spaces were observed during the first week. The immunohistochemistry revealed that myofibroblasts expressed AT1 receptor. AT1 receptor blockade or cotreatment with L-arginine, but not cotreatment with hydralazine, prevented the L-NAME-induced increase in Ang II receptors and inflammatory changes. In conclusion, rat cardiac Ang II receptors are upregulated at an early phase of chronic inhibition of NO synthesis. This may contribute to cardiovascular inflammatory changes in an early phase and to remodeling at the later phase, which occurs after inhibition of NO synthesis.

Design, synthesis and evaluation of transition-state analogue inhibitors of Escherichia coli gamma-glutamylcysteine synthetase

Phosphinic acid-, sulfoximine- and sulfone-based transition-state analogues were synthesized and evaluated as inhibitors of Escherichia coli gamma-glutamylcysteine synthetase. These compounds have a carboxyl function at the beta-carbon to the tetrahedral central hetero atom so as to mimic the carboxyl group of the attacking cysteine in the transition state. The phosphinic acid- and the sulfoximine-based compounds were found to be potent ATP-dependent inactivators, both showing a slow-binding kinetics with overall affinities and second-order inactivation rates of one to two orders of magnitude greater than those of L-buthionine (SR)-sulfoximine (L-BSO). The sulfone was a simple reversible inhibitor without causing ATP-dependent enzyme inactivation, but its affinity toward the enzyme was still five times greater than that of L-BSO, indicating that the beta-carboxyl function plays a key role in the recognition of the inhibitors by the enzyme. The sulfoximine with (S)-beta-carbon to the sulfur was synthesized stereoselectively, and the two diastereomers with respect to the chiral sulfur atom were separated as a cyclic sulfoximine derivative. The sulfoximine with R-configuration around the sulfur served as an extremely powerful ATP-dependent inactivator with an overall inhibition constant of 39 nM and an inactivation rate of 6750 M-1 s-1, which correspond to 1260-fold higher affinity and almost 1400-fold greater inactivation rate as compared with L-BSO. The sulfoximine with (S)-sulfur was a simple reversible inhibitor with an inhibition potency comparable to that of the sulfone. The synthesis and inhibition profile of the N-phosphoryl sulfoximine is also described.

Successful graft replacement of the descending aorta after an extended reconstruction of the ascending and transverse aorta in a patient with Marfan's syndrome

A 27-year-old man with Marfan's syndrome underwent a total aortic graft replacement in three separate stages. Initially the abdominal aorta was replaced, followed by the ascending aorta and aortic arch, and finally the residual portion. The extensive reconstruction of both the ascending and transverse aorta at the second operation, even though no dissection was present in the aortic arch, reduced the risk of the subsequent operation since the same surgical approach did not have to be used.

Regulation of angiotensin II receptor expression by nitric oxide in rat adrenal gland

We recently reported that administration of Nomega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) production, activates the vascular and cardiac renin-angiotensin systems and causes vascular thickening and myocardial hypertrophy in rats with perivascular and myocardial fibrosis. It has been reported that aldosterone may contribute to the development of cardiac fibrosis, but it is not known whether inhibition of NO synthesis affects angiotensin II (Ang II) receptor gene expression and aldosterone secretion. The aim of this study was to investigate the effect of NO inhibition on the expression of Ang II receptors in the adrenal gland and on aldosterone secretion in rats. Wistar King A rats received normal water, L-NAME alone (1 mg/mL in the drinking water), or L-NAME and the alpha1-adrenergic receptor blocker bunazosin (0.1 mg/mL in the drinking water) for 1 week. After 1 week of treatment with L-NAME, systolic blood pressure, plasma aldosterone concentration (PAC), and mRNA level and number of Ang II type 1 receptor (AT1-R) were increased. Plasma renin activity, serum angiotensin-converting enzyme activity, and the number of AT2-R were unchanged. Although addition of bunazosin to L-NAME restored systolic blood pressure to the control level, PAC and AT1-R numbers remained significantly higher than those of control level. These results suggest that the increased AT1-R number and PAC induced by the inhibition of NO synthesis were independent of blood pressure and systemic renin-angiotensin system. Therefore, hypertension and myocardial fibrosis induced by NO blockade may be due in part to an elevation of PAC caused by increased AT1-R in the adrenal gland.

Expression of MAGE-1, MAGE-2 and MAGE-3 genes in human gastric carcinomas; lack of evidence for cytotoxic effects in cases with simultaneous expression of MAGE-3 and HLA-A2

The human MAGE gene products are recognized by major histocompatibility complex-restricted cytotoxic T lymphocytes. We analyzed by RT-PCR the expression of MAGE-1, MAGE-2, MAGE-3 and HLA-A2 genes in 10 human gastric cancer cell lines and 46 human stomachs removed due to advanced gastric carcinomas. All the cell lines expressed MAGE genes, except for MKN-45 and -74 which lacked the expression of MAGE-1 and -3 genes in this study. Of the 46 gastric carcinomas, MAGE-1, -2 and -3 genes were expressed in 14 (30%), 10 (22%) and 26 (57%) cases, respectively, regardless of histological type. Normal gastric mucosa and intestinal metaplastic mucosa showed no expression of these genes. HLA-A2 gene expression was noted in 14 both normal and carcinoma cases. Simultaneous expression of MAGE-3 and HLA-A2 genes was noted in 7 cases. Mean apoptotic and Ki-67-labeling indices (AI and KI) of carcinoma cells were 2.3 +/- 0.5 and 48.1 +/- 6.0 in 7 cases, and 2.8 +/- 0.2 and 47.3 +/- 2.7 in the other 39 cases lacking the expression of MAGE-3 and/or HLA-A2 genes, respectively. The two-year survival rate did not differ between the two groups. Although this study confirmed the relatively higher expression of the MAGE gene family in human advanced gastric carcinomas, it might suggest that simultaneous expression of MAGE-3 and HLA-A2 genes does not necessarily imply the induction of cancer cell apoptosis by CTL.

[Cooperative inhibitory effects of cervical mucus and neutrophils on growth of Candida albicans]

Preparations of human cervical mucus were obtained from fifteen female volunteers with or without vaginal candidiasis. Their content of lactoferrin and inhibitory effects on the growth of Candida albicans were estimated. The concentration of lactoferrin in cervical mucus was measured by enzyme linked immunosorbent assay (ELISA). Lactoferrin concentration of the eleven preparations among them was more than 0.2 mg/ml. The effects of these cervical mucus preparations on Candida growth were examined in vitro. Candida growth was not inhibited by the addition of 1/200 diluted cervical mucus alone, however, anti-Candida activity of murine neutrophils was augmented by such an addition. These results suggest that the combination of neutrophils and cervical mucus may have an important role in defense against Candida infection in the vaginal mucosa.

A split cord malformation

This report describes a case of split cord malformation without a septum. A 2-year-old boy presented with a 3-month history of neurogenic bladder. MRI did not show any apparent abnormality around the conus medullaris. However, CT myelography clearly demonstrated the presence of a split filum terminale. The patient underwent laminectomy of L1-5 laminas and untethering of the split filum terminale. CT myelography was superior to MRI in diagnosing split cord malformation in this case. As MRI is currently regarded as the superior imaging modality, this reported case may have been missed because the pathology was not apparent on MRI.

Early induction of transforming growth factor-beta via angiotensin II type 1 receptors contributes to cardiac fibrosis induced by long-term blockade of nitric oxide synthesis in rats

We previously reported that the chronic inhibition of nitric oxide (NO) synthesis increases cardiac tissue angiotensin-converting enzyme expression and causes cardiac fibrosis in rats. However, the mechanisms are not known. Transforming growth factor-beta (TGF-beta) is a key molecule that is responsible for tissue fibrosis. The present study investigated the role of TGF-beta in the pathogenesis of cardiac fibrosis. The development of cardiac fibrosis by oral administration of the NO synthesis inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) to normal rats was preceded by increases in mRNA levels of cardiac TGF-beta1 and extracellular matrix (ECM) proteins. TGF-beta immunoreactivity was increased in the areas of fibrosis. Treatment with a specific angiotensin II type 1 receptor antagonist, but not with hydralazine, completely prevented the L-NAME-induced increases in the gene expression of TGF-beta1 and ECM proteins and also prevented cardiac fibrosis. Intraperitoneal injection of neutralizing antibody against TGF-beta did not affect the L-NAME-induced increase in TGF-beta1 mRNA levels but prevented an increase in the mRNA levels of ECM protein. These results suggest that the early induction of TGF-beta1 via the angiotensin II type 1 receptor plays a major role in the development of cardiac fibrosis in this model.

IR Spectroscopic Study of Adsorption of Binary Gases over Ion-Exchanged ZSM-5 Zeolites

Adsorption of binary gases (CH4/CO, CO/NO, and CO/CO2) on alkali metal (Li, Na, K, Rb, and Cs) ion-exchanged ZSM-5 zeolites were studied using IR spectroscopy. IR absorption bands of preadsorbed CH4, particularly that of nu1 (induced band), decreased with the increase in the partial pressure of CO, indicating the preferential adsorption of CO on the cation site of zeolite. In addition, IR band profiles of adsorbed CO changed in a different manner when CH4, NO, or CO2 was added to the system, suggesting that the selectivity of adsorption was governed not only by the polarity of adsorbates but also by the nature of sites present in the ZSM-5 pore bearing different electric field strengths. Copyright 1998 Academic Press.

Expression and localization of matrix metalloproteinase-12 in the aorta of cholesterol-fed rabbits: relationship to lesion development

Degradation of extracellular matrix (ECM) proteins in the aorta is a critical step for the development of atherosclerosis. Expression of matrix metalloproteinase (MMP)-12 (macrophage elastase), an elastin-degrading proteinase in the MMP family, was investigated in the thoracic aorta of rabbits fed a 1% cholesterol-containing diet for 16 weeks. In the atherosclerotic lesions, MMP-12 was produced abundantly at both the mRNA and protein levels, whereas no expression was observed in the normal rabbit aortas. The principal source of MMP-12 was macrophage foam cells (MFCs) that had infiltrated the atherosclerotic intima; this was demonstrated in both in vitro culture studies of MFCs purified from atherosclerotic lesions and immunohistochemical studies of aortic lesions. Additional biochemical studies using recombinant rabbit MMP-12 revealed that MMP-12 digested elastin, type IV collagen, and fibronectin and also activated MMP-2 and MMP-3. Expression of MMP-12 by human macrophage cell lines was increased by stimulation with acetylated low-density lipoprotein, implying augmentation of MMP-12 production during foam cell formation. Increased expression of MMP-12 in atherosclerotic lesions, concomitant with foam cell generation, which triggers the acceleration of ECM breakdown, is likely to be a critical step in the initiation and progression of the atherosclerotic cascade.

ATP-dependent inactivation of Escherichia coli gamma-glutamylcysteine synthetase by L-glutamic acid gamma-monohydroxamate

Incubation of Escherichia coli gamma-glutamylcysteine synthetase with L-glutamic acid gamma-monohydroxamate and ATP caused slow but irreversible inhibition of the enzyme, and more than 90% activity was lost in three days. The enzyme was not inactivated when ATP was absent or L-aspartic acid beta-monohydroxamate was substituted for L-glutamic acid gamma-monohydroxamate, suggesting that the inactivation process reflected a mechanism-based reaction of L-glutamic acid gamma-monohydroxamate and ATP.

Involvement of MMP-1 and MMP-3 in collagen degradation induced by IL-1 in rabbit cartilage explant culture

To determine whether matrix metalloproteinase-1 (MMP-1) or MMP-3 is involved in cartilage collagen degradation, polyclonal antibodies were separately raised against MMP-1 and MMP-3 and their effects on collagen degradation were assessed in rabbit cartilage explant culture. We found that anti-MMP-1 antibodies completely inhibited collagen degradation induced by the combination of interleukin-1 (IL-1) and plasminogen. Anti-MMP-3 antibodies showed 40% inhibition at maximum concentration. These results indicate that MMP-1, and possibly MMP-3, are involved in collagen degradation in cartilage explant culture.

Embryogenesis-promoting factors in rat serum

Regarding whole rat embryo cultures in vitro, rat serum as a culture medium is known to support the normal growth of rat embryos in the organogenesis phase. The purpose of the present study was to isolate the embryogenesis-promoting factors from rat serum as a first step in the development of a defined serum-free medium for a whole embryo culture system. Pooled rat serum after heat inactivation was fractionated into three major peaks (frA, containing a region of void volume, frB, and frC) by gel filtration. The 9.5-day rat embryos that were cultivated for 48 hr in essential salt medium containing frB (with a molecular size range of 100-500 kDa) revealed normal growth. Three proteins (27 kDa, 76 kDa, and 190 kDa) that had the embryogenesis-promoting effects were isolated from 3-hr delayed centrifuged rat serum by the ion exchange chromatography. The 76-kDa protein was found to be rat transferrin by immunoblotting. The 27-kDa protein was identified as apo-AI (the major apoprotein of high-density lipoprotein) by immunoblotting. High-density lipoprotein obtained from pooled rat serum by a NaBr density gradient ultracentrifugation was found to have a positive effect on embryogenesis. The 10-kDa protein was also identified as alpha 1-inhibitor 3 by immunoblotting. In addition, the embryogenesis-promoting effect of the fraction containing 27-kDa and 190-kDa proteins declined within a short period of storage at -20 degrees C. This decrease was countered by supplementing its fraction (D-2) with albumin isolated from rat serum. These results in the present study suggest that transferrin, high-density lipoprotein, and alpha 1-inhibitor 3 in rat serum may be embryogenesis-promoting factors, and that albumin appeared to play a role in the embryogenesis of rat embryos in whole embryo cultures.

Reconstruction for the brilliance-upgrading project of the Photon Factory storage ring

Reconstruction of the Photon Factory storage ring (PF ring; 2.5 GeV) is now in progress to provide very brilliant synchrotron radiation to users, i.e. the emittance is being reduced by a factor of five. Components, such as the quadrupole and sextupole magnets, vacuum chambers, beamlines and beam-position monitors, are being replaced by new ones in 16 normal-cell sections of the PF ring. The accelerating cavities, injection systems and control systems are also being replaced. Operation will commence when the improvements are completed on 1 October 1997.

Design of a synchrotron radiation source at Tohoku University

The construction of a third-generation light source has been proposed at Tohoku University. The emittance is 7.3 nm rad at the nominal beam energy, 1.5 GeV. The circumference is 194 m. The ring consists of 12 double-bend achromatic cells. Ten of 12 dispersion-free long straight sections are 5 m long and will be used for insertion devices and some accelerator components. The remaining two are each 15 m long and reserved for advanced devices, such as a very long undulator or a free-electron laser. A stretcher-booster ring, which is now under commission, will be used as an injector. In total, about 50 beamlines can be constructed and ten of them will be those of insertion devices. The present status of the project is 'waiting for approval'.

Single-pass BPM system of the Photon Factory storage ring

At the 2.5 GeV ring of the Photon Factory, a single-pass beam-position monitor (BPM) system is being prepared for the storage ring and the beam transport line. In the storage ring, the injected beam position during the first several turns can be measured with a single injection pulse. The BPM system has an adequate performance, useful for the commissioning of the new low-emittance lattice. Several stripline BPMs are being installed in the beam transport line. The continuous monitoring of the orbit in the beam transport line will be useful for the stabilization of the injection energy as well as the injection beam orbit.

Characterization of interpolyelectrolyte complexes between double-stranded DNA and polylysine comb-type copolymers having hydrophilic side chains

The polyionic interaction between DNA and polycations grafted with hydrophilic dextran side chains was evaluated. The comb-type copolymers, poly(L-lysine)-graft-dextran, were successfully prepared by employing a reductive amination reaction between epsilon-amino groups of poly(L-lysine) (PLL) and the reductive ends of dextran (Dex). A coupling efficacy on the order of 70% was obtained regardless of intrinsic philicities of the solvents used, either aqueous buffer or DMSO. The resulting graft copolymers, which varied in the degree of grafting and the length of hydrophilic side chains, formed a soluble complex with DNA. They also affected the melting behavior of double-stranded DNA (dsDNA) in different ways. Copolymers having a high degree of grafting thermally stabilized dsDNA without affecting its reversible transition between single-stranded and double-stranded forms. However, copolymers with a low degree of grafting or with a high degree of grafting of short dextran chains impeded the reversibility of this transition. Furthermore, highly grafted copolymers also accelerated the hybridization of DNA strands in a low-ionic strength medium. It is of particular note that these copolymers scarcely altered circular dichroismic signals of dsDNA even when the copolymers were added in excess. This suggested that the copolymer interacted with dsDNA without affecting its native structure or physicochemical properties. Finally, the copolymer even formed a stable complex with a short oligonucleotide (20 bases). We, therefore, concluded that, by regulating the degree of grafting and the molecular weight of grafted side chains, it would be possible to design novel different graft copolymers capable of acting as carriers of functional genes to target cells or tissue.

Subchronic toxicity of Di(2-ethylhexyl)phthalate in common marmosets: lack of hepatic peroxisome proliferation, testicular atrophy, or pancreatic acinar cell hyperplasia

To evaluate the toxicological effect, di(2-ethylhexyl)phthalate (DEHP) was administered orally at 100, 500, and 2500 mg/kg to four male and four female marmosets in each group for 13 weeks. Its potentials of hepatic peroxisome proliferation, testicular atrophy, and pancreatic acinar cell hyperplasia were evaluated more closely. Clofibrate, which potently causes peroxisome proliferation in rodents, was administered in like manner at 250 mg/kg as a reference drug. DEHP induced significant suppression of weight gain in males at 2500 mg/kg. However, the increase in liver mass and hypertrophy of hepatocytes were not detected in organ weight measurements or histopathological examination. The number of peroxisomes, volume density, peroxisome morphology, and peroxisomal enzyme activities were not different from those in the control group, though the males treated with 500 and 2500 mg/kg DEHP showed 1.3- and 1.4-fold increases in mean peroxisome volume, respectively. In contrast, clofibrate induced 2.2 (in male)- and 1.9-fold (in female) increases in hepatic cyanide-insensitive acyl CoA oxidation system activity, 1. 2 (in male)- and 1.7-fold (in female) increases in hepatic carnitine-dependent acetyltransferase activity, and 1.8 (in male)- and 3.0-fold (in female) increases of carnitine-dependent palmitoyltransferase activity. Cytochrome P-450 contents tended to increase in all males and females administered 500 and 2500 mg/kg of DEHP and clofibrate associated with the increase in hepatic microsomal protein content, suggesting a relationship with the treatment. The atrophic change in the testis or proliferative change in the pancreatic acinar cells seen in rodents were not seen histopathologically; also, no changes were observed in testes weight, testicular zinc level, blood levels of testosterone and estradiol, pancreas weight, and blood levels of cholecystokinin. Finally, no changes considered to be due to the administration of DEHP were noted in blood chemical examination or pathological examination of other organs.

Molecular cloning of human Frizzled-6

The Frizzled genes encode receptors for WNTs, secreted glycoproteins implicated in development as well as in carcinogenesis. In this paper, we report molecular cloning of Hfz6, the human homologue of Mfz6. Nucleotide sequence analysis showed that the Hfz6 gene encodes the 706 amino-acid protein with seven transmembrane domains, a cystein-rich domain in the N-terminal extracellular region, two N-linked glycosylation sites, and two cystein residues in the second and third extracellular loops. Hfz6 mRNA 4.4-kb in size was detected in various normal adult and fetal tissues, and a larger amount of Hfz6 mRNA was detected in both fetal lung and fetal kidney. The Hfz6 gene has been mapped to human chromosome 8q22.3-q23.1. In conclusion, we have cloned Hfz6, which encodes a seven-transmembrane receptor with the cystein-rich domain in the N-terminal extracellular region, but without the Ser/Thr-X-Val motif in the C-terminus.