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It has been demonstrated that the intermittent administration of human parathyroid hormone (hPTH) is beneficial for restoration of bone mass in osteoporotic patients. The mechanisms of anabolic effects of hPTH have been determined by ovariectomized rat models and other larger remodeling animals. However, treatment with hPTH may increase the cancellous bone mass at the expense of cortical bone mass and cessation of the treatment results in rapid bone loss. Efforts have been made to maintain newly formed bone mass after withdrawal of the hPTH treatment. These issues are not well understood. In this article, the authors would like to represent previous studies of their own and others concerning these issues.

Osteoblast progenitor cells derive from pluripotent, mesenchymal stem cells in the bone marrow stroma, and play a crucial role in the formation of bone in remodeling and fracture healing. Mechanical stimuli and humoral factors, including systemic and local growth factors, regulate the proliferation and differentiation of bone marrow stroma cells into osteoblasts. When the bone marrow cells are cultured in vitro, osteoblast progenitor cells proliferate to form colonies of cells (colony-forming unit-flbroblastic, or CFU-F), and express alkaline phosphatase (ALP). These CFU-Fs exhibit osteoblastic phenotype, and form calcified nodules in vitro. The number of nucleated cells and ALP-positive CFU-Fs in marrow specimens obtained from human ilia were quantified in order to examine the concentration of osteoprogenitor cells with osteoblastic features. Human bone marrow cells were harvested by aspiration of the anterior iliac crests of 74 female donors whose ages ranged from 2 to 88 years, and who were without systemic or metabolic bone disease. These aspirated human bone marrow cells formed calcified nodules in vitro, and exhibited osteoblastic phenotype such as the expression of ALP, osteopontin (OPN), osteocalcine (OSC), parathyroid hormone-receptor (PTH-R), collagen type III (COL-III), collagen type I (COL-I), core-binding factor-1 (CBFA-1) and bone morphogenetic protein (BMP-2) mRNAs. The 2 ml aspirates of bone marrow yielded an average total number of 81.0 ± 6.3 × 106 nucleated cells, and an average of 21.2 ± 2.4 ALP-positive CFU-Fs. There was a decrease in the number of ALP-positive CFU-Fs with age, while there was no significant correlation between the total cell number and age. These results indicate that (a) human bone marrow contains osteoblast progenitor cells, and (b) the total number of cells and the number of ALP-positive CFU-Fs in the iliac bone marrow differ from one another. However, the number of ALP-positive CFU-Fs were negatively correlated with age. These findings suggest that the number of ALP-positive CFU-Fs is one of the indices that reflect bdhe-forming activity, and bone-forming activity is related to the age-dependent change in the number of osteoprogenitor cells.

The purpose of this study was to determine the efficacy of human parathyroid hormone, hPTH (1–34), in augmenting cortical bone mass in ovariectomized (OVX) growing rats. Thirty 11-week-old female Sprague-Dawley rats were divided into five groups of six animals each. Ovariectomy was performed on 18 rats and 12 rats were subjected to sham surgery. All rats were left untreated for the 4 weeks postsurgery. At the end of pretreatment period, groups of baseline sham (Group 1) and OVX (Group 2) rats were killed. The remaining rats were divided into three groups and each treated as follows. Sham-operated rats (Group 3) and ovariectomized rats (Group 4) were injected with saline vehicle. Ovariectomized rats (Group 5) were injected with hPTH (1–34), 30jLlg/kg, five times per week. All treatments were initiated at 4 weeks postsurgery for a 4-week period. To classify the effects of PTH on cortical bone modeling and remodeling during the treatment period, the PTH-treated group was injected subcutaneously with Oxytetracycline just prior to the initiation of the PTH treatment. All animals were double-labeled with subcutaneous injections of calcein on day 6 and day 2 before euthanization. Cross sections of the tibial diaphysis were subjected to quantitative bone histomorphometry. PTH treatment of OVX rats (Group 5) increased cortical bone area and width, tended to decrease the bone marrow area, and did not significantly increase the endocortical resorbing surface compared to the vehicle-treated OVX rats. PTH administration in the OVX rats increased cortical bone by the addition of new circumferential bone on both the periosteal and endocortical surfaces by stimulating osteoblastic recruitment; the newly formed bone was lamellar in nature. PTH administration activated cortical bone modeling in the formation mode (activation-formation) on either the periosteal or endocortical envelopes. The present data indicate that PTH stimulated cortical bone modeling in the formation mode and augmented cortical bone mass in the tibial diaphysis of OVX rats. These findings are in agreement with previous observations that dogs and humans respond similarly to PTH, suggesting that PTH administration may be a useful anabolic agent in the prevention and treatment of postmenopausal osteoporosis.

Intermittent administration of human parathyroid hormone (hPTH) (1–34) activates bone formation and increases cancellous bone mass in ovariectomized (OVX) rats. However, PTH-induced increases in cancellous bone volume rapidly decrease to the original levels after withdrawal of hPTH(l-34). Besides confirming that intermittent PTH administration increases cancellous bone mass, this study determined whether PTH-induced cancellous bone mass could be maintained by running exercise after PTH treatment was discontinued, whether a bisphosphonate, incadronate disodium (YM-175), could also maintain that bone, and, if so, whether that maintenance effect persisted after YM-175 withdrawal. Eleven-week-old Sprague-Dawley rats were OVX and hPTH (1–34), 30 μg/kg, was injected subcutaneously three times per week for 12 weeks, beginning 1 week after OVX in experiment 1, and for 8 weeks beginning 4 weeks after OVX in experiment 2. After withdrawal of PTH, treadmill exercise was done for the next 8 weeks (15.7m/min, 1h/day, 5 days/week), or YM-175, 10 μg/kg, was injected subcutaneously three times per week for 4 weeks. In the proximal tibial metaphysis, histomorphometric analysis with standard bone histomorphometry and node-strut analyses revealed that hPTH administration partially prevented OVX-induced cancellous bone loss. Eight weeks after PTH administration stopped, PTH-induced increases in cancellous bone mass had returned to the OVX/V (vehicle injection) level. Treadmill exercise helped to maintain the PTH-induced bone mass but did not increase bone mass in OVX control rats. YM-175 administration maintained the PTH-induced additions to tibial cancellous bone mass after PTH treatment stopped and even for 8 weeks after treatment with YM-175 had also stopped.

Osteosarcomas are malignant tumours producing osteoid and/or bone. It is difficult to distinguish tumour bone formation from reactive, based on their morphological features alone. The objective of this study was two-fold: to clarify the origins of bone-forming cells in human osteosarcoma transplanted into nude mice; and to examine the role of bone morphogenetic proteins (BMPs) in the tumour-induced osteogenesis. DNA in situ hybridization was carried out with digoxigenin (DIG) polymerase chain reaction (PCR) labelled DNA probes for human-specific ‘Alu’ and mouse-specific ‘mouse L1 (m-L1)’ genes. Human osteosarcoma cells, established cell lines of NOS-1, NOS-2, and HuO9, were transplanted separately into nude mice. Bone-forming cells of the bone in the NOS-1 or NOS-2 tumours were positive for Alu, while they were negative for m-L1. The cells lining the surface of trabeculae in the HuO9 tumour were positive for Alu, but a few of them were also positive for m-L1. The m-L1-positive cells expressed mouse osteocalcin and type I collagen mRNAs. These facts suggest that the mouse cells were involved in osteoid synthesis of the HuO9 tumour. The NOS-1 or NOS-2 tumours expressed human BMP 2–7 mRNAs, whereas the HuO9 tumour expressed human BMPs 2, 4, 5, and 7. The osteogenetic potential of the tumours may depend on the expression patterns of BMPs. These results demonstrate two distinct types of bone formation, by tumour cells and by an admixture of tumour and non-tumour cells. The present study showed that the HuO9 tumour produces chimeric bone formation. This is the first report to demonstrate the relationships between tumour cells and non-tumour cells in bone formation, using genetic markers. © 1998 John Wiley & Sons, Ltd.

Recently, an imaging technique using microcomputed tomography (micro-CT) has emerged as a method for nondestructively assessing the microarchitecture of unprocessed surgical bone biopsy specimens. Using micro-CT, two-dimensional (2D) axial images were obtained from undecalcified transiliac bone biopsies which were taken from 15 patients with various metabolic bone diseases. Total area, bone area, and bone perimeter were determined, from which the bone volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) were calculated semiautomatically and instantaneously. To evaluate the validity of this technique as a useful tool, the results were compared with those obtained from conventional histomorphometry. There were significant correlations between the two techniques for all parameters, with correlation coefficients ranging from 0.759 (Tb.N, P < 0.005) to 0.949 (BV/TV, P < 0.0001). Different resolutions seem to lead to major differences in perimeter values measured by the two methods. These factors may explain why the correlation coefficients of Tb.N and Tb.Th estimated from the perimeter and area is lower than that of BV/TV. Our results show that the micro-CT based on 2D images is a useful tool for imaging and nondestructively quantifying the microarchitecture of trabecular bone in unprocessed surgical bone specimens.

This study assessed the effect of low dose human parathyroid hormone [hPTH(1-34)] administration on cancellous and cortical bone of lumbar vertebrae in intact male beagles. 16 19-20-month-old beagle dogs were randomized into four groups: in group 1, the vehicle control group, saline was injected daily; in group 2, the sequential group, 0.375 microg/kg of PTH was injected daily for 4 weeks, then off 8 weeks, and this sequence was once repeated for another 4 and 8 weeks; in group 3, the same dose of PTH was injected once per week for 24 weeks; and, in group 4, PTH was injected three times per week for 24 weeks. Histomorphometric assessment on cancelllous and cortical bone (both ventral and dorsal shell) and two-dimensional node-strut analysis were done on the fifth lumbar vertebral bodies after calcein double bone labeling. In intact adult beagles, on the group treated with 0.375 microg/kg per day three times per week (group 4): (1) had a higher mean value in cancellous bone formation parameters [osteoid surface (+74%), osteoid volume (twofold), mineral apposition rate (+21%), and bone formation rate (twofold)]; (2) exhibited no effect on cortical thickness and porosity in both the ventral and dorsal shell; and (3) showed a lower mean value of node to termini (0.11 +/- 0.02 vs. 0.22 +/- 0.09) and a higher mean value of cortex to node (0.18 +/- 0.06 vs. 0.08 +/- 0.02), but not in trabeculae to trabeculae node, than age-related controls. In conclusion, we found that a low dose of PTH administration: (1) stimulated cancellous bone formation; (2) improved connectivity of trabeculae joined to the cortex; (3) did not decrease cortical thickness; and (4) did not increase cortical porosity in both ventral and dorsal cortexal shell of the lumbar vertebrae during this dosage and period in intact male beagles.

We demonstrated a single-substrate polymer-stabilized blue phase liquid crystal (PSBP LC) display using a bar-coating technique. The BP temperature range and the electro-optical (EO) properties of PSBP LC cells fabricated on a single-substrate of glass, polycarbonate (PC) and polyethylene terephthalate (PET) were investigated. It was found that PSBP LC cells fabricated on the single-substrate of glass, PC, and PET exhibited a narrower BP temperature range in comparison with the conventional PSBP LC cell. This is necessary to improve the mechanical stability, the thermal stability and the EO performance of the single-substrate PSBP LC cells.

Dear Editor, Here, we reply to the letter to the editor about our study [1]. As pointed out, the original article written by Ueno [2], which we cited, does not define the threshold value of joint space width for classification. However, the original article was written in Japanese, and Takatori et al. [3] translated it to English. Additionally, Takatori et al. [3] recommended the modified staging classification in this translated article. It was recommended that the classification criteria should involve the joint space width in order to divide stage 2 (early stage) and stage 3 (advanced stage). Clinically, the classification of hip osteoarthritis is often used as a modified version, but a unified consensus has not yet been reached by the Japanese Orthopedic Association (JOA) Committee. In our study, we used the modified classification. However, we made an incorrect citation and should have cited the translated article by Takatori et al. with the modified classification in addition to the original article by Ueno. Therefore, our citation misled the reader and caused confusion to the authorized people of JOA. We would like to take this opportunity to apologize and correct the citation. Conflict of interest None.

Histomorphometric studies were conducted in rats to determine whether bone particles would disturb new bone formation on the interface of titanium implants inserted after reaming of the marrow cavity. In eighty 10-week-old female Wistar rats, smooth-surfaced titanium alloy implants were inserted bilaterally into the marrow cavity after reaming in the distal femur. There were three experimental groups: in the irrigated femora, sterile saline was flushed through the medullary canal; in the particle femora, autologous bone particles were inserted into the intramedullary cavity; and in the reamed femora, the implant was inserted without procedures after reaming. The rats were sacrificed at one, two, four or eight weeks postoperatively, and Villanueva bone staining was applied for histomorphometric studies. The bone volume of new bone on the interface of the implant in the irrigated femora was greater than that in the particle or the reamed femora throughout the study period. The results suggest that clearance of bone particles by irrigation after reaming of the marrow cavity significantly facilitates new bone formation on the interface of implants by one week. The findings also suggest the potential clinical application of total canal irrigation prior to insertion of cementless femoral components as well as cemented prosthesis.

To distinguish the origin of bone-forming cells in the osteosarcoma (OST) tumor inoculated into nude mice, we have developed a novel in situ hybridization technique. The system used digoxygenin (DIG) labeled DNA probes that encoded human specific repetitive gene, Alu, and mouse specific repetitive gene, mouse L1 (m-L1). The chondrogenic and osteogenic cells in the tumor had strongly positive signals for m-L1 probe without any signals for Alu probe. The expression of bone matrix proteins was also examined by in situ hybridization. The bone-forming cells were positive for mRNAs of mouse osteonectin, osteopontin, and osteocalcin relating to calcification during bone formation, while these were negative for human mRNAs of these bone matrix proteins. The OST cells in the tumor expressed the human bone morphogenetic proteins (BMPs) mRNAs by RT-PCR. These data indicated that the mouse cells, not the human sarcoma cells, are responsible for cartilage and bone formation in the OST tumor inoculated into nude mice, and we speculated that BMPs, at least in part, could play an important role in this ossification.

Two forms of the transmembrane human protein tyrosine phosphatase (PTP sigma), generated by alternative splicing, were identified by cDNA cloning and Northern hybridization with selective cDNA probes. The larger form of PTP sigma is expressed in various human tissues, human osteosarcoma, and rat tibia. The hPTP sigma cDNA codes for a protein of 1911 amino acid residues and is composed of a cytoplasmic region with two PTP domains and an extracellular region that can be organized into three tandem repeats of immunoglobulin-like domains and eight tandem repeats of fibronectin type III-like domains. In the brain, the major transcript of PTP sigma is an alternatively spliced mRNA, in which the coding region for the fibronectin type III-like domains number four to seven are spliced out, thus coding for a protein of 1502 amino acid residues similar to the rat PTP sigma and rat PTP-NE3. Using in situ hybridization, we assigned hPTP sigma to chromosome 6, arm 6q and band 6q15. The bacterial-expressed hPTP sigma exhibits PTPase activity that was inhibited by orthovanadate (IC50 = 0.02 microM) and by two bisphosphonates used for the treatment of bone diseases, alendronate (ALN) (IC50 = 0.5 microM) and etidronate (IC50 = 0.2 microM). In quiescent calvaria osteoblasts, micromolar concentrations of vanadate, ALN and etidronate stimulate cellular proliferation. These findings show tissue-specific alternative splicing of PTP sigma and suggest that PTPs are putative targets of bisphosphonate action.

Intermittent treatment with human parathyroid hormone (1-34) [hPTH(1-34)] stimulates bone formation and increases cancellous bone mass in ovariectomized (OVX) rats. But PTH-induced cancellous bone rapidly disappears upon cessation of treatment. The fate of cortical bone treated by PTH has not been well characterized. Incadronate disodium (disodium cycloheptylaminomethylenedisphosphonate monohydrate, YM175) was expected to be antiresorptive without inhibiting bone formation. The purposes of this study were to determine (1) whether PTH treatment increases new cancellous and cortical bone mass and bone formation, (2) whether the new bone could be maintained by YM175 sequential treatment, and (3) whether the maintenance effect is persistent after YM175 withdrawal. Eighty-eight 11-week-old Sprague-Dawley rats were divided into sham operation and OVX groups. The OVX rats were treated for 8 weeks with the subcutaneous intermittent injection of 30 micrograms/kg of hPTH(1-34) three times a week beginning 4 weeks after surgery, then PTH treatment was withdrawn and YM175 (10 micrograms/kg) was injected subcutaneously three times a week for 4 weeks. YM175 treatment was withdrawn for the last 8 weeks of the protocol. The results of microstructural assessment in proximal tibial metaphysis and bone mineral density in distal and proximal femur demonstrated that PTH treatment for 8 weeks restored bone mass to the sham control level. However, after cessation of PTH treatment, the PTH-induced tibial cancellous bone mass showed a decrease at 4 weeks and almost totally disappeared after 12 weeks. Conversely, YM175 treatment maintained the PTH-induced tibial cancellous bone mass, and the bone continued to be maintained after 8 weeks of withdrawal of the YM175. Cortical bone was not lost during PTH treatment. YM175 maintained the PTH-induced new tibial cancellous bone in OVX rats by suppressing remodeling.

We demonstrated the differences of response between trabecular and cortical bone sites in the rat induced by OVX and hPTH(1–34) administration [subcutaneous injection, 30μg/kg, 3 times/week, for 12 weeks] and its withdrawal [for 8 weeks]. We observed that hPTH(1–34) administration in OVX rats partially prevented OVX-induced cancellous bone loss in the proximal tiabial metaphysis and added cortical bone in the tibial shaft. After cessation of hPTH treatment, bone loss was observed both in trabecular and cortical bone; however, it was more dramatic on endocortical surfaces.

In order to examine the mechanism of the anabolic effect of parathyroid hormone (PTH) on bone formation, human PTH(1-34) [hPTH(1-34)] (30 micrograms/kg) was injected subcutaneously to 9-week-old rats 5 times a week for 1 or 3 weeks. Trabecular bone volume (BV/TV) in the tibial metaphysis was not significantly different between the PTH- and vehicle-treated groups, but the parameters related to bone formation, including osteoid surface (OS/BS), mineralizing surface (MS/BS), mineral apposition rate (MAR), and bone formation rate (BFR/BS), were significantly increased as early as 1 week after PTH treatment. And the parameters related to bone resorption including eroded surface (ES/BS) and osteoclast number (N.Oc/BS) were also significantly increased as early as 1 week after PTH treatment. Treatment with PTH for 1 week induced no significant increase in bone mineral density at the femoral metaphysis, whereas the same treatment for 3 weeks induced a significant increase. When bone marrow cells isolated from femora and tibiae of either PTH- or vehicle-treated rats were cultured at a high density (2 x 10(7) cells/one well of 24-multiwell plate), cellular alkaline phosphatase (ALP) activity was significantly increased in the cells isolated from PTH-treated rats compared with vehicle-treated rats. When bone marrow cells were cultured at a low density (4 x 10(6) cells/a one well of 6-multiwell plate) to generate colonies (colony forming unit-fibroblastic, CFU-F), PTH induced apparent increases in both the total number of CFU-F and the number of ALP-positive CFU-F.(ABSTRACT TRUNCATED AT 250 WORDS)

NER, a new member of the steroid hormone nuclear receptor (NR)-encoding gene family, was isolated from a human osteosarcoma SAOS/B10 cell line cDNA library. NER codes for a polypeptide of 461 amino acids which contains the conserved sequences of the DNA-binding and ligand-binding domains of typical steroid hormone NR. It has highest homology with the retinoic acid receptors: 55% at the DNA-binding domain and 38-40% at the ligand-binding domain. A single transcript of 2.3 kb was detected in all cells and tissues tested. Although no ligand was identified for NER-I, its wide distribution may indicate that this novel steroid hormone NR may play a basic role in cell function.

Reports of five young women who developed vertebral fractures associated with pregnancy and lactation are presented (Fig. 1). Ages ranged from 24 to 37 (mean 30) years. All five patients have osteoporosis with two to nine vertebral fractures at presentation postpartum. Bone mineral density (BMD) was measured by single-photon absorptiometry, quantitative computer tomography, and dual-energy X-ray absorptiometry. BMD of the trabecular bone was less than normal values and it remained apparently low even several years after pregnancy. Histological findings of bone biopsy identified the bone loss with increasing bone resorption. Our present findings suggest that postpregnancy osteoporosis affects mainly the trabecular bone site, and the patients might have low peak bone mass and poor reversibility probably due to a low rate of remodeling.

Insulin-like growth factors (IGF-I and IGF-II) are among the most abundant growth factors found in bone. Although their local production has been implicated in growth and development, localization of the cells that express these proteins is not well documented. We have studied, by in situ hybridization, the temporal and spatial expression of IGF-I and IGF-II mRNA in rat long bones at different stages of postnatal bone development. In 2-day-old rats, IGF-II was highly expressed in cartilage and in the mesodermal structures that surround the bone. At later stages of bone development, the IGF-II signal decreased in intensity, but could still be detected in the growth plate of tibial bones at 3 and 5 weeks. At this stage, the IGF-II signal in the epiphyseal growth plate was unevenly distributed and was stronger in the periphery than in the center, where it was mainly concentrated in the germinal layer and in some, but not all, cartilage columns. IGF-I, on the other hand, was only faintly detected in the periosteum at the early cartilaginous stage of bone development. At later stages, IGF-I was strongly associated with regions of ossification in the trabecular bone of the metaphysis and epiphysis and along the endosteal and periosteal surfaces. Surprisingly, we did not detect at any time IGF-I mRNA in chondrocytes of the epiphyseal growth plate. These results suggest that in the rat, IGF-II plays a role in early development of bone and in the longitudinal growth of the epiphyseal plate. IGF-I is more closely associated with the osteogenic regions and does not replace the declining levels of IGF-II in the growth plate.

Oncolytic adenoviruses are being developed as novel antitumor therapeutics and currently undergoing clinical trial. Telomelysin (OBP-301) is a type 5 adenovirus that contains the replication cassette in which the human telomerase reverse transcriptase promoter drives expression of the E1 genes, and shows telomerase specific replication and cell killing effect. We previously demonstrated that the expression of coxsackie-adenovirus receptor (CAR) is high in osteosarcoma compared with the other mesenchymal tumors, and moreover, many investigators have been reported that telomerase expression predicts the unfavorable outcome in osteosarcoma. The present investigation analyzed that the selective replication and antitumor effects of Telomelysin using 8 osteosarcoma and 1 normal dermal fibroblast cell lines in vitro as well as in vivo by using athymic mice carrying xenografts. At first, all cell lines were used to examine the mRNA expression of CAR and hTERT, and 3 osteosarcoma cell lines and 1 normal fibroblast cell were chosen for Telomelysin infection. Selective E1A and E1B expression were shown in osteosarcoma cells by quantitative real-time RT-PCR and Western blot analysis, but not in normal cells such as human dermal fibroblasts. Telomelysin replicated efficiently and induced marked cell death in osteosarcoma cells, whereas replication as well as cytotoxicity was highly attenuated in normal fibroblast cells lacking telomerase activity. Expression of cleaved caspase, PARP and LC-3 I, II after Telomelysin infection was tested by Western blot, however the mechanism of induction of cell death could not be revealed in this time. For in vivo evaluation, nu/nu mice xenografted with NOS10 human osteosarcoma cell received intratumoral injection of 107 plaque-forming units of Telomelysin, and resulted in a significant inhibition of tumor growth and long-term survival in all treated mice. Moreover, selective replication of Telomelysin in tumor cell was also demonstrated by anti-E1A immunohistochemistly, and induction of apoptosis was observed by TUNEL staining. Our results suggest that the hTERT promoter confers competence for selective replication of Telomelysin in osteosarcoma cells, and the outcome has important implications for tumor-specific oncolytic chemovirotherapies for human osteosarcomas. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2593.

We have identified a novel member of the steroid hormone receptor superfamily by cDNA cloning from a human osteosarcoma SAOS-2/B10 cell library. Sequence analysis predicts a protein of 441 amino acids, which includes the conserved amino acid residues characteristic of the DNA- and ligand-binding domains of nuclear receptors. Amino acid sequence alignment and transcriptional activation experiments revealed that the new protein is closely related to the mouse peroxisome proliferator activated receptor. The overall homology is 62%, and the highest similarity is seen in the DNA- and ligand-binding domains, 86% and 71%, respectively. Northern blot analysis showed that in mature rats, the receptor is highly expressed in heart, kidney, and lung as a transcript of approximately 3500 nucleotides. In human cells, the size of the mRNA is approximately 4000 nucleotides. Transcription assays using hybrid receptors consisting of the ligand-binding domain of the new protein and the DNA-binding domain of the glucocorticoid receptor showed weak stimulation by the peroxisome proliferator activator WY14643, suggesting a relationship to that receptor. Similar stimulation was observed with arachidonic and oleic acid (100-250 microM).

Nicotinamide (NA) and its four isomeric methyl analogs [2-, 4-, 5- and 6-methylnicotinamides (MNs)] were tested as substrates for nicotinamide N-methyltransferase (NNMT) and amine N-methyltransferase (ANMT) using rat liver, kidney, spleen and brain 9000 x g supernatant fluids as model enzyme preparations. The N-methylated products were determined fluorometrically by their reaction with acetophenone or 4-methoxybenzaldehyde to form fluorescent 2,7-naphthyridine derivatives, and the lower limits of the determination were 8-30 pmol/100 microliters. N-Methyltransferase activities were detected in the liver with NA, 4-MN and 5-MN, and in the brain and spleen with 4-MN. On this basis, 5-MN is considered to be a selective substrate for NNMT in addition to NA, which is a known methyl acceptor for this enzyme. Although 4-MN appears to serve as a methyl acceptor for both ANMT and NNMT, it seems to be essentially a selective substrate for brain ANMT because of the absence of NNMT in brain. The fluorometric methods used here are also very useful because of their simplicity, sensitivity and selectivity.

There are many reports on cup placement, inclination, anteversion, and position. This article strictly defines the area of cup placement based on data from 185 healthy hip centers and Ranawat's triangle. Linear wear rate (LWR) was measured in 55 total hip arthroplasty (THA) cases and categorized as low or high. The relationships between these categories and cup size, inclination, anteversion, position, age, follow-up period, bone graft, cup osteolysis, and stem osteolysis were investigated.