Mouse placental cells secrete immunoreactive growth hormone-releasing factor

The initial objective of this study was to establish a placental cell culture system in which the secretion of mouse growth hormone-releasing factor (mGHRF) could be examined during a several-day period. To determine when during pregnancy placental cells begin to express mGHRF, Northern blot analysis was carried out on total RNA from placentas collected on Days 6, 9, 11, 13, 15, 17, and 18 of pregnancy. Mouse GHRF mRNA could be detected as early as Day 11 of pregnancy. Its steady-state levels increased to maximum values on Days 15-17 and then declined slightly on Day 18. Placentas from Day 12 of pregnancy were selected for cell culture. The basal zone and labyrinth were dispersed in collagenase, and the cells were fractionated on a Percoll gradient. Two bands of cells were selected for further study. Both released significant amounts of immunoreactive mGHRF during a 5-day culture period. Effects of prolonged exposure of the cells to 8-bromo-cAMP and to agents that elevate intracellular cAMP concentration were then examined. Treatment of the cells with 0.5 mM 8-bromo-cAMP resulted in a significant decrease in the mGHRF concentration of the medium by the second day of culture. Mouse GHRF secretion was also inhibited by treatment of the cells with 100 ng/ml cholera toxin or 0.1 mM forskolin. The effect of 8-bromo-cAMP was concentration-dependent, with 0.1 mM being the lowest concentration that was active. 8-Bromo-cAMP treatment also reduced the steady-state level of mGHRF mRNA in the cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Transforming growth factor-beta 1 post-transcriptionally inhibits mouse growth hormone releasing factor secretion in placenta

The aim of this study was to investigate whether TGF-beta 1 regulates mouse GHRF secretion by primary cultures of placental cells from day 12 of pregnancy. Ten ng/ml TGF-beta 1 significantly inhibited mouse GHRF secretion by the third day of culture. The lowest concentration of TGF-beta 1 that significantly inhibited mouse GHRF secretion was 1 ng/ml. The inhibitory effect of TGF-beta 1 on mouse GHRF secretion was completely eliminated by addition of an anti-TGF-beta 1 antibody. Steady-state levels of mouse GHRF mRNA as assessed by Northern analysis was not reduced by incubation of placental cells from day 12 of pregnancy with 10 ng/ml TGF-beta 1 for 5 days. Both placenta and decidua expressed TGF-beta 1 mRNA, and the level of TGF-beta 1 mRNA in decidua increased during gestation while the level of TGF-beta 1 mRNA was constant throughout gestation. These findings suggest that TGF-beta 1 is one of the potent regulators of mouse GHRF secretion and that TGF-beta 1 regulates mouse GHRF secretion in an autocrine or paracrine manner in the mouse placenta in vivo.

[A survey on elderly patients' knowledge of management of health care]

We conducted a questionnaire survey on the awareness of elderly patients in our hospital concerning medical management. As to the recognition of their own diseases, patients aged 80 or older, showed a lower degree of understanding than those under age 80. The proportion of patients who wished to known about their diagnosis decreased with age, although no statistical significance was recognized. Those who wished to known about their diagnosis, even if it were malignant, reduced significantly depending on the increase in age. In addition, the proportion of patients who would not like to know their diagnosis, if it were malignant, increased significantly as age increased. Proportions of patients who wanted to know other information, such as prognosis, the aims, methods and results of medical examination, the methods and adverse effects of treatment, and the names, effects and side effects of drugs, also decreased significantly as age increased. However, there were no statistical significant differences in the proportion of answers between cases of malignant and non-malignant disease. These data show that elderly patients had more anxiety or fear about malignancy, and wished to know less about medical management than non-elderly patients.

An osteometrical study of the cranium and mandible of Ryukyu wild pig in Iriomote island

We measured crania and mandibles of Ryuku wild pigs from Iriomote Island. Sex and age were determined by observation of lower teeth. From the present data, the growth pattern was established for some items. For several parts of the cranium and mandible, the relative growth coefficient was compared. The results obtained here are summarized as follows: (1) Although sexual dimorphism was already shown in the younger group, a significant difference in profile length and length from the angle was not seen in the adult group. (2) As the animal grew, the proportion of length to width became larger in the skull. (3) The visceral cranium grew more rapidly in length than the cerebral cranium. On the other hand, growth of the cerebral cranium contributed to width in cranial development. (4) The body of the mandible was shown to grow more rapidly in length than the ramus of the mandible. (5) The growth pattern of some items was related to that of their associated muscles. These basic data are expected to be compared with data from other population of the same subspecies and Japanese wild pig. The comparisons will contribute to the establishment of origin and phylogeny of this animal.

Gene structure and cell type-specific expression of the human ATP synthase alpha subunit

The gene structure of the human ATP synthase alpha subunit (hATP1) was determined by cloning and sequencing. This gene is approximately 14 kbp in length and contains 12 exons interrupted by 11 introns. Mapping of the clones of hATP1 and Southern blot analysis of the genomic gene showed that there were a single copy of bona fide hATP1 gene and two pseudogenes. Primer extension and S1 mapping analysis showed the presence of multiple transcription initiation sites of the hATP1 gene. No TATA box or CAAT box was found near the transcription initiation sites. Comparison with the bovine gene showed that the 5'-flanking region of the hATP1 gene has an unconserved guanine-cytosine (GC) rich region, including several binding motifs of transcriptional factors, such as Sp1, AP-2, and GCF. By functional assay of gene expression, the basal promoter activity was located near the GC rich region. Comparison of the 5'-upstream region of the hATP1 gene with those of the genes for bovine ATP synthase alpha, human beta, and human gamma subunits indicated three common sequences, suggesting that putative cis-elements coordinate the expressions of the three subunit genes for the ATP synthase. The enhancer activities derived from the 5'-deletion mutants of a hATP1-CAT chimeric gene were different in cell lines from four different human tissues, suggesting the existence of cell type-specific gene regulation.

Involvement of S100-related calcium-binding protein pEL98 (or mts1) in cell motility and tumor cell invasion

We examined the relationship between cell motility and the expressions of pEL98 (mts1) mRNA and protein in various murine normal and transformed cells. The expression of pEL98 (mts1) in v-Ha-ras-transformed NIH3T3 cells and in normal rat kidney cells transformed by either v-Ha-ras or v-src was increased over that in the corresponding parental cells at both mRNA and protein levels. The expression in normal rat fibroblasts (3Y1) transformed by v-Ha-ras was also increased compared with that in 3Y1 cells. However, the expression of pEL98 (mts1) in 3Y1 cells transformed by v-src was increased in one clone (src 3Y1-K), but decreased in another clone (src 3Y1-H). The expression level of pEL98 (mts1) correlated well with cell motility, which was examined by measuring cell tracks by phagokinesis. In order to test direct involvement of the pEL98 (mts1) protein in cell motility, src 3Y1-H cells that showed low cell motility were transfected with pEL98 cDNA. The transfectants expressing large amounts of the pEL98 protein showed significantly higher cell motility than src 3Y1-H cells. The expression of pEL98 (mts1) was also found to be correlated with motile and invasive abilities in various clones derived from Lewis lung carcinoma. These results suggest that the pEL98 (mts1) protein plays a role in regulating cell motility and tumor cell invasiveness.

Effects of KCA-098 on bone metabolism: comparison with those of ipriflavone

We previously found that 3,9-bis(N,N-dimethylcarbamoyloxy)-5H- benzofuro[3,2-c]quinoline-6-one (KCA-098) inhibited bone resorption in organ culture. In this study, to determine if KCA-098 is therapeutically applicable for the treatment of osteoporosis, we compared the effect of KCA-098 on bone tissues with that of ipriflavone, a drug that is clinically used for the treatment of osteoporosis. Both KCA-098 and ipriflavone inhibited parathyroid hormone-, prostaglandin E2-, 1 alpha,25-dihydroxyvitamin D3- and interleukin 1 beta-induced bone resorption of fetal rat bones, but the inhibitory activity of KCA-098 was more potent than that of ipriflavone. In fact, the effective concentrations of KCA-098 were 10 to 100 times lower than those of ipriflavone. Oral administration of KCA-098 (1 and 3 mg/kg) or ipriflavone (100 mg/kg) to ovariectomized rats on a low-calcium diet increased the breaking force and bone density of the femora, indicating that KCA-098 is an effective on the whole animal as ipriflavone. Furthermore, KCA-098 increased the length and calcium content of 9-day chick embryonic femora cultured in vitro, whereas ipriflavone did not, suggesting that KCA-098 had a direct stimulatory effect on bone mineralization. Therefore, KCA-098 seems to be more potent than ipriflavone in stimulating bone tissue formation and may thus be expected to become a useful agent for the treatment of osteoporosis.

Mutagenic specificity of 2-amino-3-methylimidazo[4,5-f]quinoline and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine in the supF shuttle vector system

2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are heterocyclic amine mutagens/carcinogens formed from the cooking of meat. Here we used the pSP189 shuttle vector developed by Parris and Seidman (Gene, 117: 1-5, 1992) to study and compare the mutation spectra induced by these compounds. pSP189 was adducted by reaction with the N-acetoxy derivatives of IQ or PhIP. 32P-Postlabeling analysis was used to measure the C8-guanine adduct level and the total adduct levels formed in the plasmid. Plasmids were replicated and mutagenized in repair-proficient [GM0637(SV40)] or repair-deficient [XP12Be(SV40)] human fibroblasts. Resulting inactivation mutations in the supF gene were determined by the formation of white or light blue colonies on indicator bacteria (carrying a lacZ amber mutation) and cycle sequencing. With both compounds in either cell line, 85-93% of the mutations induced were base substitutions and the remainder of the mutations were base deletions. The majority of the substitution mutations involved a single base, and nearly all base substitution mutations (> 97%) were at guanine. This latter finding is consistent with the results from 32P-postlabeling showing that both compounds adduct to the guanine base with the major adduct being formed at the C8-guanine position. The predominant mutation found with IQ and PhIP in either cell line was G:C to T:A transversion, followed by G:C to A:T transition, and then G:C to C:G transversion; these mutations accounted for 59-72%, 19-27%, and 6-14% of total base substitution mutations, respectively. There was a preference seen with both compounds to induce mutations at a guanine base having a neighboring guanine or cytosine (i.e., GG and GC sites). However, despite the striking similarity in the kinds of base substitution mutations induced by IQ and PhIP, their mutation spectra were distinct. For example, in repair-proficient cells, 26% of the mutations induced with PhIP, but not with IQ, also involved a GA site, containing the 5-base pair sequence 5'-GCAGA-3'. Mutation spectra for IQ and PhIP were also different between repair-deficient and repair-proficient cells. The findings shown here may serve to be predictive of the kinds of mutations induced by the adducts of IQ and PhIP in oncogenes and tumor suppressor genes altered during heterocyclic amine-induced carcinogenesis.

Acrylamide alters neurofilament protein gene expression in rat brain

Acrylamide, a prototype neurotoxin, alters neurofilament protein (NF) gene expression in rat brain. Levels of mRNA coding for neurofilament protein subunits NF-L, NF-M, and NF-H have been determined by Northern blot analysis using 32P-labeled cDNA probes. Acrylamide given acutely (100 mg/kg, single intraperitoneal injection) causes a selective increase in NF-M mRNA (approximately 50%) compared to controls. The expression of NF-L or NF-H mRNA is not affected by acrylamide. In contrast, chronic treatment with acrylamide [0.03% (w/v) in drinking water for 4 weeks] induces a modest but significant increase (approximately 22%) in NF-L mRNA compared to controls. Levels of NF-M, and NF-H mRNA are not altered by acrylamide treatment. The expression of beta-actin mRNA, an ubiquitous protein, is not affected by either treatment regimen of acrylamide. The results of this study show that acrylamide increases the expression of mRNA for NF protein subunits in rat brain. The increase of specific mRNA for NF subunits depends on the dose, duration and route of acrylamide administration.

Induction of osteopenia in confined rats

We have developed a simple model of osteopenia in rats which is induced by confinement without requiring surgical operation. Each rat was maintained for 8 weeks in a compartment of a commercially-available wire netting cage subdivided into 10 areas (compartment size, 9 x 16 x 14 cm) to restrict exercise. The femora isolated from the confined rats showed significant decreases in mineral (calcium and phosphorus) content, compared with the level in normal rats, 2 weeks after the start of their confinement. Confined rats showed significantly lower values for the physical properties of bones such as breaking energy and breaking force and also density composed with normal rats 4 weeks after the start of confinement. KCA-098 (1 mg/kg), a new benzofuroquinoline derivative that inhibits bone resorption and at the same time stimulates bone mineralization in organ culture, protected against these decreases when given orally for 8 weeks. All these results show that confinement of rats offers a simple and useful animal model of osteopenia.

Antitumor effect of biological response modifier, PSK, on C57BL/6 mice with syngeneic melanoma B16 and its mode of action

The effects of PSK, a protein-bound polysaccharide, on the survival period and effector cell activity were examined using C57BL/6 mice with melanoma B16. PSK prolonged the survival period of the mice with tumors in a schedule- and dose-dependent manner. However, no life-prolonging effect was observed when carrageenan-treated mice or congenitally athymic mice were used as hosts. PSK enhanced the cytostatic activity and interleukin-1-producing capacity of peritoneal exudate plastic-adherent cells in C57BL/6 mice with tumors. These findings suggested that PSK prolongs the survival period of mice with B16 tumors through T-cell- and macrophage-dependent mechanisms.

Cytoskeletal neurofilament gene expression in brain tissue from Alzheimer's disease patients. I. Decrease in NF-L and NF-M message

The cytoskeletal changes seen in brains of patients with Alzheimer's disease include neurofibrillary tangles, neuritic plaques, Hirano bodies, and granulovacuolar degeneration. Northern and slot blot analyses were used to investigate the expression of the genes coding for actin, tubulin, neurofilaments, and histone in brain tissue from Alzheimer's disease patients and normal aged controls. We found a marked decrease of 94% in the expression of the neurofilament gene coding for the medium size subunit (150 kDa) and a 73% decrease in the expression of the gene coding for the small subunit (68 kDa) in Alzheimer's disease patients as compared to controls. Expression of the other genes, such as actin and histone, did not show any significant difference. Expression of the gene coding for medium size, neurofilament gene was not decreased in other neurodegenerative diseases, such as amyotrophic lateral sclerosis and Parkinson's disease. This abnormality in neurofilament gene expression may explain some of the pathologic features found in Alzheimer's disease patients.

Chondroitin sulfate proteoglycans protect cultured rat's cortical and hippocampal neurons from delayed cell death induced by excitatory amino acids

Protective effects of chondroitin sulfate proteoglycans (CSPGs) from rat's brain against delayed cell death induced by excitatory amino acids were examined in cultured neurons of the rat. CSPGs reduced delayed neuronal death induced by 10 min exposure to glutamate at a concentration between 100 microM and 1 mM when lactate dehydrogenase activity of culture medium was assayed 24 h after the exposure. CSPGs also protected neuronal death induced by 200 microM N-methyl-D-aspartate (NMDA), kainate or 100 microM alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA). CSPGs reduced death of cortical and hippocampal neurons even when they were administered at 2 h, but not 6 and 12 h, after the exposure to glutamate. These results indicate that CSPGs may have a neuroprotective action against acute noxious conditions in the brain.

Antineutrophil cytoplasmic autoantibodies in 6 patients with renal failure and systemic sclerosis

OBJECTIVE

To elucidate the distribution and frequency of antineutrophil cytoplasmic autoantibodies (ANCA) in systemic sclerosis.

METHODS

Patient sera were analyzed by indirect immunofluorescence and by enzyme linked immunosorbent assay.

RESULTS

High titers for perinuclear ANCA correlated with rapid deterioration of renal function. Patients were normotensive with normal plasma renin levels, but anemia, pulmonary hemorrhage and thrombocytopenia were problematic. All patients had anti-myeloperoxidase antibodies and some had anti-nRNP, anti-DNA, anti-Sm and LE cell antibodies. Outcome was poor except for one patient treated by plasmapheresis and cyclophosphamide.

CONCLUSION

A renal specific subset of systemic sclerosis is suggested.

Exclusion of an alternatively spliced exon in human ATP synthase gamma-subunit pre-mRNA requires de novo protein synthesis

Tissue-specific isoforms of the mitochondrial ATP synthase gamma-subunit are generated by alternative splicing, and the heart/skeletal muscle-specific transcript lacks exon 9 in a cassette fashion (Matsuda, C., Endo, H., Hirata, H., Morosawa, H., Nakanishi, M., and Kagawa, Y. (1993) FEBS Lett. 325, 281-284; and Matsuda, C., Endo, H., Ohta, S., and Kagawa, Y. (1993) J. Biol. Chem. 268, 24950-24958). Here, we show that the endogenous heart-type mRNA is cell-specifically induced by the extracellular pH value in the HT1080 (human fibrosarcoma) and KYM-1 (human rhabdomyosarcoma) cell lines. In these cells, a low extracellular pH value induced exclusion of exon 9, and this induction was inhibited by cycloheximide treatment. In contrast, a high extracellular pH value resulted in mRNA transcription of the liver type, including exon 9, and did not require de novo protein synthesis. These results suggest that alternative splicing in the gamma-subunit pre-mRNA is regulated by on-off switching of protein synthesis of a trans-acting factor involved in this exon-excluding step. The signal of low pH value was blocked by the protein kinase inhibitor H-7 or Calphostin C (protein kinase C inhibitor), indicating the involvement of protein kinase C in the alternative splicing. This is a good model system for studies on the induction mechanism of alternative splicing in cultured mammalian cells, in which intracellular factors play a pivotal role for the exon-excluding step in the tissue-specific alternative splicing mechanism.

Comparison of the ATPase activities of bovine heart and liver mitochondrial ATP synthases with different tissue-specific gamma subunit isoforms

The kinetics of heart and liver mitochondrial ATPase (FoF1) were examined using submitochondrial particles (SMPs) purified from the two tissues to obtain information on the role of gamma subunit isoforms. The F1 portion is mainly composed of the catalytic, common alpha beta subunits and tissue-specific gamma subunits. In contrast to the previous reports on the kinetics and crystallography of various F1's, the Vmax and Km of the two isoforms of FoF1 were identical although the SMPs were prepared from different tissues. Moreover sodium azide inhibited the two equally. The ATPase activity of liver SMP showed slightly steeper pH-dependency than that of heart SMP but the pH optima of the two were the same (pH 8).

Purification of rabbit C-reactive protein by affinity precipitation with thermosensitive polymer

A method of purifying rabbit C-reactive protein (CRP) based on affinity coprecipitation with a thermosensitive polymer is developed. This polymer, which was obtained by conjugation of p-aminophenylphosphorylcholine (APPC) and poly-N-isopropylacrylamide derivative with reactivity to primary amino groups, exhibited a thermally reversible phase separation profile with a critical value at 32 degrees C and high affinity for CRP in the presence of Ca2+. When rabbit acute-phase serum was incubated with APPC-conjugated polymer in the presence of Ca2+ at 4 degrees C, only CRP was bound to this affinity polymer and coprecipitated by raising the temperature of the incubation mixture above 32 degrees C. After addition of cold EDTA solution to the precipitate followed by centrifugation at 38 degrees C, CRP was recovered from the polymer in more than 80% yield with no contaminants. The binding of CRP to APPC-conjugated polymer was dependent on concentrations of both CRP and the polymer.

Effect of KCA-098, a new benzofuroquinoline derivative, on bone mineral metabolism

The effect of 3,9-bis(N,N-dimethylcarbamoyloxy)-5H-benzofuro[3,2-c]quinoli ne-6-one designated as KCA-098) on the bone mineral metabolism of chick embryonic bone was examined. KCA-098 dose-dependently inhibited bone resorption of cultured chick embryonic femora and calvariae. It increased the length, dry weight, and calcium and phosphorus contents of 9-d-old chick embryonic femurs cultivated for 6 d, indicating that it stimulated bone formation. These results show that KCA-098 has the unique effects of inhibiting bone resorption and stimulating bone formation of chick embryo. In addition, in an in vivo experiment, oral administration of KCA-098 (3.0 mg/kg/d) for 16 weeks led to an increase in calcium and phosphorus content as well as an increase in the amount of force required to break the femur from ovariectomized rats, suggesting that it may be useful for the treatment of bone diseases.

Experimental arthritis induced by continuous infusion of IL-8 into rabbit knee joints

To determine the roles of IL-8 in inflammatory synovitis, examination was made of the results of continuously injecting human recombinant IL-8 into the knee joints of New Zealand while rabbits. Recombinant human IL-8 was infused continuously into the joint cavity at 75 ng/h for 14 days by a polypropylene catheter connected to a mini-osmotic pump implanted in each rabbit. Infiltration of inflammatory cells into joint cavity and histopathological changes in synovial tissue were examined at 7 and 14 days following the start of infusion. The continuous infusion of IL-8 for 14 days led to severe arthritis characterized by apparent erythema and joint pain, the accumulation of leucocytes, infiltration of mononuclear cells in synovial tissue, and marked hypervascularization in the synovial lining layer. IL-8 may be a factor which can contribute to the inflammatory process of chronic arthritis by mediating leucocyte recruitment and hypervascularization in inflamed joints.

Essential involvement of interleukin-8 in neutrophil recruitment in rabbits with acute experimental arthritis induced by lipopolysaccharide and interleukin-1

Rheumatoid arthritis and related inflammatory joint diseases are characterized by massive infiltration of polymorphonuclear cells (PMN) into inflamed joints. Interleukin-8 (IL-8) has recently been identified as a leukocyte chemotactic and activating factor produced by activated tissue cells as well as monocytes/macrophages. Examination was made of the involvement of IL-8 in acute arthritis induced by injecting lipopolysaccharide (LPS) or interleukin-1 alpha (IL-1 alpha) into the joints of rabbits. The neutralizing antibody to rabbit IL-8 blocked almost completely the infiltration of PMN into the joints and provided protection from damage to tissue in the early phase of inflammation induced by LPS or IL-1 alpha. Mononuclear cell infiltration observed later was not inhibited by this antibody. This is the first paper to clearly demonstrate that IL-8 is an essential and major mediator determining whether PMN infiltration will occur in the early phase of experimental acute arthritis.

Binding of pEL98 protein, an S100-related calcium-binding protein, to nonmuscle tropomyosin

The cDNA coding for mouse fibroblast tropomyosin isoform 2 (TM2) was placed into a bacterial expression vector to produce a fusion protein containing glutathione-S-transferase (GST) and TM2 (GST/TM2). Glutathione-Sepharose beads bearing GST/TM2 were incubated with [35S]methionine-labeled NIH 3T3 cell extracts and the materials bound to the fusion proteins were analyzed to identify proteins that interact with TM2. A protein of 10 kD was found to bind to GST/TM2, but not to GST. The binding of the 10-kD protein to GST/TM2 was dependent on the presence of Ca2+ and inhibited by molar excess of free TM2 in a competition assay. The 10-kD protein-binding site was mapped to the region spanning residues 39-107 on TM2 by using several COOH-terminal and NH2-terminal truncation mutants of TM2. The 10-kD protein was isolated from an extract of NIH 3T3 cells transformed by v-Ha-ras by affinity chromatography on a GST/TM2 truncation mutant followed by SDS-PAGE and electroelution. Partial amino acid sequence analysis of the purified 10-kD protein, two-dimensional polyacrylamide gel analysis and a binding experiment revealed that the 10-kD protein was identical to a calcium-binding protein derived from mRNA named pEL98 or 18A2 that is homologous to S100 protein. Immunoblot analysis of the distribution of the 10-kD protein in Triton-soluble and -insoluble fractions of NIH 3T3 cells revealed that some of the 10-kD protein was associated with the Triton-insoluble cytoskeletal residue in a Ca(2+)-dependent manner. Furthermore, immunofluorescent staining of NIH 3T3 cells showed that some of the 10-kD protein colocalized with nonmuscle TMs in microfilament bundles. These results suggest that some of the pEL98 protein interacts with microfilament-associated nonmuscle TMs in NIH 3T3 cells.

In vitro effect of KCA-098, a derivative of coumestrol, on bone resorption of fetal rat femurs

The effects of 3,9-bis(N,N-dimethylcarbamoyloxy)-5H-benzofuro[3,2-c]quinoli ne-6-one (KCA-098), a derivative of coumestrol, on bone resorption was studied in organ cultures of 20-day fetal rat femora. KCA-098 increased the length, dry weight, and calcium and phosphorus contents of parathyroid hormone (PTH)-treated fetal rat femur. As PTH significantly reduced the calcium and phosphorus contents of the femora, probably by stimulating bone resorption, KCA-098 seems to inhibit bone resorption. In fact, KCA-098 inhibited the PTH-induced release of 45Ca from pre-labeled fetal rat femora into the medium in organ culture. Coumestrol also inhibited the release of 45Ca from bone into the medium. However, KCA-098 did not increase the uterine weight of ovariectomized rats, whereas coumestrol did so. Thus KCA-098 is a unique, new inhibitor of bone resorption that has no estrogenic activity.

A protective action of chondroitin sulfate proteoglycans against neuronal cell death induced by glutamate

The role of chondroitin sulfate proteoglycans (CSPGs) on excitotoxic cell death and long-term survival of neurons were investigated in primary cultured neurons of the rat cortex. Soluble CSPGs were prepared from 10-day-old and adult rat brains by the ion-exchange chromatography on DEAE-Sephacel. CSPGs were added to the culture medium on culture day 4, and glutamate neurotoxicity was examined on culture day 7 by both microscopic cell count and measurement of lactate dehydrogenase activity in culture media. The effect on long-term survival was evaluated by counting viable neurons until culture day 28. CSPGs and core proteins, but not glycosaminoglycan chains (GAGs), protected cultured neurons from excitotoxic cell death induced by 24 h exposure to 1 mM glutamate, but CSPGs did not promote the long-term survival of neurons. The neuroprotective effect of CSPGs and core proteins was dose-dependent with ED50 about 10 microM hexuronate and 2 micrograms/ml protein respectively. This effect was not considered to be due to adsorption of glutamate by CSPGs because [3H]glutamate was not adsorbed by CSPGs added to the culture medium. Based on these findings, we suggested that CSPGs may exert their neuroprotective action through molecular interactions with the binding sites on neuronal membrane, neurotrophic factors, or other extracellular matrix molecules and may be involved in the pathogenesis of neuronal cell death in acute pathological conditions and chronic degenerative diseases of the brain.

A novel cDNA, priBc, encoding a protein with a Zn(II)2Cys6 zinc cluster DNA-binding motif, derived from the basidiomycete Lentinus edodes

A cDNA clone (designated priBc) was isolated from a primordial cDNA library of the basidiomycete, Lentinus edodes (Le). The priBc clone consisted of 2628 bp encoding 565 amino acids. As was expected, the priB transcript was abundant in primordia, while preprimordial mycelia and mature fruiting bodies contained lower levels of this Le transcript. The deduced PRIB protein (64 kDa) contained a 'Zn(II)2Cys6 zinc cluster' DNA-binding motif. PRIB was produced in Escherichia coli using the bacteriophage T7 expression system. Southwestern blot analysis revealed that PRIB binds to the DNA fragment containing the upstream region of priB.

Afterload reduction by hydralazine in children with a ventricular septal defect as determined by aortic input impedance

Hydralazine was administered at cardiac catheterization to eight children with a ventricular septal defect (age: 2.2-8.8 years), and the extent of afterload reduction was determined using aortic input impedance and wall stress. The pulmonary to systemic blood flow ratio decreased from 2.2 +/- 0.8 to 1.8 +/- 0.4 (p < 0.05) and the pulmonary systemic resistance ratio increased from 0.11 +/- 0.08 to 0.13 +/- 0.10 (p < 0.05) after hydralazine administration. Hydralazine reduced mean aortic pressure and the amplitude of the late systolic peak of the aortic pressure wave. Peak flow velocity in the descending aorta increased from 62 +/- 14 to 81 +/- 24 cm/sec (p < 0.05). Peripheral resistance decreased significantly from 13.3 +/- 5.9 to 6.6 +/- 3.7 10(3) dyn sec/cm3 (p < 0.05). The modulus of the first harmonic, indicating pulse wave reflection, decreased from 1196 +/- 575 to 815 +/- 382 dyn sec/cm3 (p < 0.05). The characteristic impedance, indicating aortic stiffness, did not change. End-systolic wall stress decreased significantly from 54.4 +/- 16.7 to 34.8 +/- 10.2 g/cm2 (p < 0.01). Hydralazine acutely achieved afterload reduction by reducing both peripheral resistance and pulse wave reflection, and increased stroke volume.