bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of monoclonal and polyclonal antibody-based immunoassays for osteocalcin: A study of sources of variation in assay results
Authors: Tracy R. P. , Andrianorivo A. , Riggs B. L. , Mann K. G. 
Published: February 2010

Abstract
We have compared two assays for osteocalcin (BGP, bone gla protein), one based on a monoclonal antibody, the other based on a polyclonal serum, in an effort to better understand the factors that contribute to the wide variation reported for osteocalcin normal ranges. The two assays compared well using serum samples, with a correlation coefficient of 0.9071 (n = 48). However, the monoclonal antibody assay returns values increased over the polyclonal assay by approximately 1.5-fold. Gel permeation studies indicate that these larger values are due primarily to increased reactivity in the monoclonal assay with high- and low-molecular-weight forms of osteocalcin in plasma; both assays give similar reactions to intact osteocalcin. Analysis of samples from individuals with increased bone resorption due to parathyroid hormone administration reveals that the decrease seen in osteocalcin values after hormone infusion occurs primarily in the fraction that corresponds to intact osteocalcin.
During the course of these studies, we re-evaluated the extinction coefficient for osteocalcin, arriving at the value E = 1.33 mg/ml−1, cm−1. We also observed a significant negative interference in both assays (and a commercial assay) caused by hemolysis. This interference is due to proteolysis of osteocalcin by enzymatic activity released from the lysed red cells.
Characterization and hormonal modulation of il-1 binding in neonatal mouse osteoblastlike cells
Authors: Dr. Shen Victor , Cheng Su-Li , Kohler Nancy G. , Peck William A. 
Published: February 2010

Abstract
Considerable evidence indicates that interleukin-1 (IL-1) is a potent regulator of bone cell activity. Consequently, we studied its binding to neonatal mouse osteoblastlike cells. Purified, labeled recombinant IL-1α bound specifically to neonatal mouse osteoblastlike cells with a dissociation constant of 30-200 pM at 22°C. There were 3000-15,000 receptors per cell. IL-1 bound to cell surfaces at 4°C was rapidly internalized when the temperature was raised to 37°C. Receptor specificity was confirmed by demonstrating that, among a series of 11 polypeptides, only IL-1 inhibited 125I-IL-1 binding. Treatment of surface-bound 125I-IL-1α with a bivalent water-soluble cross-linker identified a membrane peptide of Mr 70,000 cross-linked to IL-1. The apparent IL-1 receptor was solubilized from a plasma membrane-enriched fraction using 3-[(3-cholamido-propyldimethylammonio]-1-propanesulfonate (CHAP). The resulting material exhibited specific IL-1 binding. Preincubation of cells with IL-1, retinoic acid, transforming growth factor ß (TGF-ß), or phorbol ester caused a reduction in apparent receptor numbers per cell, while preincubation with epidermal growth factor (EGF), dexamethasone, or parathyroid hormone (PTH) increased receptor numbers per cell. Preincubation with insulin, vitamin D, prostaglandin E2 (PGE2), interferon-γ (IFN-γ), and 17ß-estradiol had no effect. These results suggest that specific, high-affinity IL-1 receptors are present on osteoblastlike cells and that the receptor number can be modified by various osteotropic agents. Regulation of bone cell IL-1 receptors may contribute to the control of bone remodeling.
1α,25-dihydroxyvitamin D3-induced increments in hepatocyte cytosolic calcium and lysophosphatidylinositol: Inhibition by pertussis toxin and 1ß,25-dihydroxyvitamin D3
Authors: Baran Daniel T. , Sorensen Ann M. , Honeyman Thomas W. , Ray Rahul , Holick Michael F. 
Published: February 2010

Abstract
1α,25-Dihydroxyvitamin D3 rapidly increases cytosolic calcium and alters membrane phospholipid metabolism in hepatocytes. To define the causal relationship between these events, we examined the effects of 1α,25-dihydroxyvitamin D3 on 32P-labeled lysophosphatidylinositol levels and cytosolic calcium as affected by pertussis toxin and 1ß,25-dihydroxyvitamin D3, the biologically inactive analog. 32P-labeled lysophosphatidylinositol was determined by two-dimensional thin-layer chromatography. Cytosolic calcium was measured in cells loaded with quin-2AM. Within 5 min, 1α,25-dihydroxyvitamin D3 increased hepatocyte cytosolic calcium by 31% (p &lt; 0.05) and 32P-labeled lysophosphatidylinositol by 38% (p &lt; 0.05). Pertussis toxin inhibited the hormone-induced rise in cytosolic calcium but not the increase in 32P-labeled lysophosphatidylinositol. Exposure to exogenous lysophosphatidylinositol for 5 min increased cytosolic calcium by 40% (p &lt; 0.05), an effect that was also inhibited by pertussis toxin. 1ß,25-Dihydroxyvitamin D3 had no effect on either hepatocyte cytosolic calcium or 32P-labeled lysophosphatidylinositol but prevented the 1α,25-dihydroxyvitamin D3-induced increments. The results suggest that a G protein sensitive to pertussis toxin is required for the transduction of the lysophosphatidylinositol signal but not the generation of the signal. The ability of 1ß,25-dihydroxyvitamin D3 to inhibit the 1α,25-dihydroxyvitamin D3-induced changes in phospholipids suggests that the epimer may compete with 1α,25-dihydroxyvitamin D3 for an initiating receptor.
Lateral dual-photon absorptiometry: A new technique to measure the bone mineral density at the lumbar spine
Authors: Uebelhart D. , Duboeuf F. , Meunier P. J. , Dr. Delmas P. D. 
Published: February 2010

Abstract
Bone mineral density (BMD) measurement of the lumbar spine by dual-photon absorptiometry (DPA) using a radioactive source and more recently an x-ray tube (DEXA) is a useful noninvasive technique to assess bone loss in vertebral osteoporosis. Because an anteroposterior (AP) projection is used, DPA measures not only the mainly trabecular bone of the vertebral body but also the cortical bone of the posterior processes, which does not contribute to the development of crushed fractures. Using a DPA apparatus equipped with a 153 Gd source coupled with an 18-detector system that provides better collection efficiency for the narrow beam of 153 Gd radiation, we have developed a technique measuring the BMD of the vertebral body of L2, L3, and L4 on a lateral projection based on previous studies using radiographic photodensitometry for lateral spine. The precision of the method — 1.7% in vivo and 0.88% in vitro — is similar to that obtained with the AP projection (respectively, 1.7 and 1.0%). Lateral BMD decreased with age in 143 normal women and was best accounted for by a cubic curve (r = −0.51, p &lt; 0.001). The age-related bone loss between 30 and 80 years of age was much higher with the lateral (-44%) than with the AP (-22%) projection, a pattern consistent with the greater trabecular than cortical age-related bone loss. When osteoporotics (OP) were compared to age-matched normal women, the decreased in BMD was larger with the lateral (-30%) than with the AP projection (-23%), but in terms of Z scores, no difference could be found between both projections. Correlation between AP and lateral BMD was highly significant in the normal women (r = 0.58, p &lt; 0.001) but not in the OP (r = 0.22, NS), indicating a predominant loss of the spongy bone in patients with vertebral osteoporosis. The influence of an osteoarthritis of the posterior processes on BMD according to the projection was assessed in 15 patients; expressed in Z score, the mean value was high with the AP projection (+1.26 SD) but normal (+0.20 SD) with the lateral projection, confirming that posterior OA interferes substantially with AP BMD.
In conclusion, BMD measurement of the vertebral body is achievable by lateral DPA with a good precision. Applied to the new DEXA densitometers, this technique should be even more precise and accurate. Lateral DPA avoids the interference of posterior OA, a common problem in the elderly, and seems to be more sensitive than conventional anteroposterior DPA to detect early vertebral bone loss. It should be valuable in the clinical investigation of osteoporosis.
Localization of the gene responsible for the op (osteopetrotic) defect in rats on chromosome 10
Authors: Remmers Elaine F. , Du Ying , Ding Yan-Ping , Kotake Shigeru , Ge Lynn , Zha Hongbin , Goldmuntz Ellen A. , Wilder Ronald L. , Hansen Carl 
Published: February 2010

Abstract
Osteopetrosis, a skeletal disorder of inadequate bone resorption with an abnormal increase in skeletal mass, results from a variety of independent single gene mutations that affect osteoclast differentiation and/or function. The osteopetrotic defect, op, is one of four spontaneous, nonallelic mutations in rats that result in osteopetrosis. In intercross progeny of (BN/SsN x LEW/SsN.+/op) F1 carriers, we mapped this locus by linkage analysis with microsatellite markers to rat chromosome 10. The linkage group contained, as well as op, 15 anonymous DNA loci and 9 DNA loci associated with genes (interleukin-3, myosin heavy chain [skeletal, embryonic], asialoglycoprotein receptor [hepatic lectin]-1, vesicle-associated membrane protein [synaptobrevin-2], sex hormone binding globulin, aldolase C, nitric oxide synthase [inducible], erythroblastic leukemia avian viral oncogene homolog-2, and proline-rich protein). The markers for these loci include nine not previously reported. The op locus mapped to the end of the chromosome 10 linkage group, within 1 cM of the anonymous DNA locus, D10Mit6. Based on its location, the op gene is likely to be distinct from seven described mutations in mice as well as three other mutations in rats. These results may permit a positional cloning strategy to be undertaken to identify the gene and mutation underlying the op defect.
Lack of evidence for an increase in interleukin-6 expression in adult murine bone, bone marrow, and marrow stromal cell cultures after ovariectomy
Authors: Vargas Socorro J. , Naprta Anica , Lee Sun-Kyeong , Kalinowski Judith , Kawaguchi Hiroshi , Pilbeam Carol C. , Raisz Lawrence G. , Lorenzo Joseph A. 
Published: February 2010

Abstract
Interleukin-6 (IL-6) has been implicated as a mediator of postmenopausal bone loss. In vitro studies of bone and bone marrow cells have suggested that estrogen regulates bone turnover by controlling the production of IL-6, a potent stimulator of osteoclastogenesis and bone resorption. To investigate this hypothesis in an in vivo model, we examined the effect of ovariectomy or estrogen replacement on IL-6 mRNA and protein expression in adult mouse bone and bone marrow in vivo and in marrow stromal cell cultures. Eight-week-old CD-1 mice were sham-operated (SHAM), ovariectomized (OVX), or ovariectomized and subcutaneously implanted with 21-day slow-release pellets containing 10 μg of 17β-estradiol (O+E). Placebo pellets were implanted in the SHAM and OVX mice. Uterine weights at 1, 2, or 3 weeks after surgery were significantly decreased (68–76%) in OVX animals compared with SHAM or O+E. In mice sacrificed at 1 or 3 weeks after surgery, we found by nonquantitative reverse transcribed polymerase chain reaction (RT-PCR), that SHAM, OVX, and O+E calvariae (CALV) constitutively expressed IL-6 mRNA. In contrast, IL-6 mRNA was either barely detectable or absent in the tibia (TIB) and bone marrow (BM). In the mice sacrificed 3 weeks after surgery, we determined by quantitative RT-PCR that IL-6 mRNA in the CALV from the OVX and O+E groups were decreased by 81 and 92%, respectively, compared with SHAM. IL-6 protein levels in the flushed bone marrow (BMSups) were detectable and were not significantly different among the groups. In bone marrow cells that were cultured for 1 week, basal levels of IL-6 protein were low and did not differ significantly among the SHAM, OVX, or O+E groups sacrificed 1, 2, or 3 weeks after surgery. After the addition of hrIL-1α, IL-6 protein levels increased 100- to 1300-fold over control. IL-6 levels in cells from animals sacrificed 2 weeks after surgery were significantly lower in the hrIL-1α-stimulated OVX and O+E groups than in hrIL-1α-stimulated SHAM cell cultures. In conclusion, in this model we could find no increase in IL-6 production with in vivo estrogen withdrawal in calvaria, long bones, bone marrow, or marrow stromal cell cultures. If increases in IL-6 expression are involved in the effects of estrogen withdrawal on bone, the magnitude of these changes are relatively small and below the limits of detection of the assays that we employed.
Chronic axial compression of the mouse tail segment induces MRI bone marrow edema changes that correlate with increased marrow vasculature and cellularity
Authors: Papuga M. Owen , Proulx Steven T. , Kwok Edmund , You Zhigang , Rubery Paul T. , Dougherty Paul E. , Hilton Matthew J. , Awad Hani A. , Schwarz Edward M. 
Published: February 2010

AbstractMagnetic resonance imaging (MRI) of bone marrow edema (BME) has been found to be helpful in the diagnosis of back pain attributed to degenerative disk disease (DDD) and spondyloarthropathy (SA), but its interpretation is limited by a lack of knowledge of its nature and natural history. We assessed effects of compressive forces to mouse tail segments of WT and TNF‐Tg mice with SA, via contrast enhanced‐MRI and histology. Normalized marrow contrast enhancement (NMCE) of uninstrumented WT vertebrae significantly decrease, threefold (p < 0.01) from 8 to 12 weeks of age, while the NMCE of TNF‐Tg vertebrae remained elevated. Compressive loading (6× body weight) increased NMCE twofold (p < 0.02) within 2 weeks in WT tails, which was equal to 6× loaded TNF‐Tg tails within 4 weeks. Histology confirmed degenerative changes and that load‐induced NMCE corresponded to increased vascular sinus tissue (35 ± 3% vs. 19 ± 3%; p < 0.01) and cellularity (4,235 ± 886 vs.1,468 ± 320 cells/mm2; p < 0.01) for the loaded versus unloaded WT, respectively. However, micro‐computed tomography (CT) analyses failed to detect significant load‐induced changes to bone. While the bone marrow of loaded WT and TNF‐Tg vertebrae were similar, histology demonstrated mild cellular infiltrate and increased osteoclastic resorption in the WT tails versus severe inflammatory‐erosive arthritis in TNF‐Tg joints. Significant (p < 0.05) decreases in cortical and trabecular bone volume in uninstrumented TNF‐Tg versus WT vertebrae were confirmed by micro‐CT. Thus, chronic load‐induced DDD causes BME signals in vertebrae similar to those observed from SA, and both DDD and SA signals correlate with a conversion from yellow to red marrow, with increased vascularity. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1220–1228, 2010
Extracellular matrix expression of human tenocytes in three‐dimensional air–liquid and PLGA cultures compared with tendon tissue: Implications for tendon tissue engineering
Authors: Stoll Christiane , John Thilo , Endres Michaela , Rosen Christian , Kaps Christian , Kohl Benjamin , Sittinger Michael , Ertel Wolfgang , Schulze‐Tanzil Gundula 
Published: February 2010

AbstractTenocyte transplantation may prove to be an approach to support healing of tendon defects. Cell–cell and cell–matrix contacts within three‐dimensional (3D) cultures may prevent tenocyte dedifferentiation observed in monolayer (2D) culture. The present study compares both neotissue formation and tenocyte extracellular matrix (ECM) expression in 2D and 3D cultures directly with that of native tendon, in order to determine optimal conditions for tendon tissue engineering. Primary human tenocytes were embedded in poly[lactic‐co‐glycolic‐acid] (PLGA)‐scaffolds and high‐density cultures. Neotissue formation was examined by hematoxyline–eosine (H&E) and immunofluorescence staining. Gene expression of ECM proteins and vascular endothelial growth factor (VEGF) was compared at days 0 (2D), 14, and 28 in 3D cultures and tendon. Histomorphology of 3D culture showed tendon‐like tissue as tenocyte cell nuclei became more elongated and ECM accumulated. Type I collagen gene expression was higher in 2D culture than in tendon and decreased in 4‐week‐old 3D cultures, whereas type III collagen was only elevated in high‐density culture compared with tendon. Decorin and COMP were reduced in 2D and increased in 3D culture almost to ex vivo level. These results suggest that the 3D high‐density or biodegradable scaffolds cultures encourage the differentiation of expanded monolayer tenocytes in vitro to tendon‐like tissue. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1170–1177, 2010
Anti‐biofilm activity of sub‐inhibitory povidone‐iodine concentrations against Staphylococcus epidermidis and Staphylococcus aureus
Authors: Oduwole Kayode O. , Glynn Aaron A. , Molony Diarmuid C. , Murray David , Rowe Sarah , Holland Linda M. , McCormack Damian J. , O'Gara James P. 
Published: February 2010

AbstractBiomaterial‐related infections continue to hamper the success of reconstructive and arthroplasty procedures in orthopaedic surgery. Staphylococci are the most common etiologic agents, with biofilm formation representing a major virulence factor. Biofilms increase bacterial resistance to antimicrobial agents and host immune responses. In staphylococci, production of polysaccharide intercellular adhesin (PIA) by the enzyme products of the icaADBC operon is the best understood mechanism of biofilm development, making the ica genes a potential target for biofilm inhibitors. In this study we report that the antibacterial agent povidone‐iodine (PI) also has anti‐biofilm activity against Staphylococcus epidermidis and Staphylococcus aureus at sub‐inhibitory concentrations (p < 0.001). Inhibition of biofilm by PI correlated with decreased transcription of the icaADBC operon, which in turn correlated with activation of the icaR transcriptional repressor in Staphylococcus epidermidis. These data reveal an additional therapeutic benefit of PI and suggest that studies to evaluate suitability of PI as biomaterial coating agent to reduce device‐related infections are merited. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1252–1256, 2010
Current neoadjuvant strategies in rectal cancer
Authors: Julien Lucas A. , Thorson Alan G. 
Published: February 2010

AbstractTreatment modalities in rectal cancer have undergone a slow, evolutionary transition over the past 30 years. More recently, contemporary descriptions of advanced preoperative chemotherapy and radiation schema have led to a rapid revolution in the management of this disease. In this review we focus on current evidence‐based neoadjuvant strategies used in the treatment of locally advanced rectal cancer and metastatic rectal disease. Finally, we provide a foundation for discussion of still unresolved issues. J. Surg. Oncol. 2010; 101:321–326. © 2010 Wiley‐Liss, Inc.
The role of neoadjuvant chemotherapy in treating advanced epithelial ovarian cancer
Authors: Weinberg Lori E. , Rodriguez Gustavo , Hurteau Jean A. 
Published: February 2010

AbstractThe current management of advanced ovarian cancer consists of aggressive primary cytoreductive surgery (PCS) followed by combination platinum based chemotherapy. Recent studies have suggested that platinum‐based chemotherapy may be of benefit in patients with advanced ovarian cancer prior to cytoreductive surgery (neoadjuvant chemotherapy, NACT). The concept of NACT has not been completely validated in the treatment of ovarian cancer. This review will discuss the role of NACT in patients with advanced epithelial ovarian cancer. J. Surg. Oncol. 2010; 101:334–343. © 2010 Wiley‐Liss, Inc.
Fast separation and determination of coumarins in Fructus cnidii extracts by CEC using poly(butyl methacrylate‐co‐ethylene dimethacrylate‐co‐[2‐(methacryloyloxy)ethyl] trimethylammonium chloride) monolithic columns
Authors: Wang Jiajing , Chen Danxia , Chen Zhao , Fan Guorong , Wu Yutian 
Published: February 2010

AbstractA rapid CEC method with poly(butyl methacrylate‐co‐ethylene dimethacrylate‐co‐[2‐(methacryloyloxy)ethyl] trimethylammonium chloride) monolithic column has been developed for separation and determination of four coumarins (isopimpinelline, bergapten, imperatorin, and osthole) in Fructus cnidii extracts. The effect of polymerization condition including the monomers ratio and the porogens ratio were studied. The mobile‐phase composition, such as the composition of organic solvent, the concentration and pH of buffer, was also optimized. Under the same condition (50% ACN and 50% of a 10 mM sodium dihydrogen phosphate electrolyte at pH 4.95), in contrast to 25 min of analysis time in HPLC and 10 min of analysis time in pCEC, a fast separation of these analytes was achieved in less than 5 min in CEC. Method validation was developed in accordance with the analytical procedures. Intra‐ and interday precisions (RSD) for relative retention time and peak area were less than 1.69 and 4.63%, and LODs were lower than 0.5 μg/mL. Calibration curves of four compounds also showed good linearity (r2>0.995). The mean recoveries ranged between 93.91 and 98.65%. With this CEC system, the quality of F. cnidii extracts from various resources was evaluated by determining the contents of the four coumarins.
A quantitative CE method to analyse tau protein isoforms using coated fused silica capillaries
Authors: Bohoyo Diego , Le Potier Isabelle , Rivière Céline , Klafki Hans , Wiltfang Jens , Taverna Myriam 
Published: February 2010

AbstractWe evaluated the potential of CE to analyse different isoforms of unphosphorylated recombinant tau protein and for separating one phosphorylated tau from the respective unphosphorylated protein. Different capillary coatings such as polyacrylamide, poly‐(ethylene oxide) and polybrene (PB) were evaluated to overcome the poor efficiencies obtained with fused‐silica capillary. Although peak asymmetry values were quite similar for the three investigated coatings, the peak efficiencies were 35‐fold and 5‐fold higher with PB coating than with polyacrylamide and poly(ethylene oxide) coatings, respectively. The recovery percentage (over 97%) was satisfactory and confirmed the efficacy of PB coating to limit the adsorption of tau protein to capillary walls. Moreover, PB coating produced higher repeatability for migration times (RSD values <1.2%) in comparison to the neutral coatings. The potential of PB‐modified capillary in producing high resolutive separations of one phosphorylated tau isoform from its unphosphorylated counterpart and of a mixture of phosphorylated and unphosphorylated tau peptides was demonstrated with 50 mM phosphate buffer pH 3.0. The separation of unphosphorylated tau isoform 352 (Tau‐352) from Tau‐352 phosphorylatedin vitroby the mitogen‐activated protein kinase ERK2, was accomplished in less than 15 min.
Hydrophilic interaction chromatography coupled to MS for metabonomic/metabolomic studies
Authors: Spagou Konstantina , Tsoukali Helen , Raikos Nikolaos , Gika Helen , Wilson Ian D. , Theodoridis Georgios 
Published: February 2010

AbstractHydrophilic interaction chromatography (HILIC) is a relatively recently introduced mode of liquid‐phase separations. Recently, HILIC has been used for coupling to MS in metabonomic/metabolomic studies to provide a complementary tool to the widely used reversed‐phase (RP) chromatographic separations. The combination of HILIC with MS detection covers a number of polar metabolites that are typically nonretained in RPLC‐mode separations and thus enlarging the number of detected analytes. This way of metabolite profiling thus provides more comprehensive metabolome coverage than using RP chromatography alone. This review describes the applications and the utility of HILIC‐MS in metabolomic/metabonomic studies and highlights certain characteristic examples in the life and plant‐food sciences.