bluuebunny/crossref_metadata_2025 huggingface dataset:
Parathyroid hormone, but not prostaglandin E2, changes the shape of osteoblasts maintained on bone in vitro
Authors: Boyde A. , Jones Sheila J. , Ali Nadire N. , Melhuish Pauline B. , Bennett A.
Published: February 2010

Parietal bones from 2-week-old rats were dissected free from the sutural regions, dura mater, and periosteum, leaving the surface covered with osteoblasts and some osteoclasts. Prostaglandin (PG) production by these “stripped” bones under basal conditions and after exposure to parathyroid hormone (PTH) was measured by radioimmunoassay of the culture medium (minimum essential medium with or without added 10% heat-inactivated fetal calf serum). Cultured specimens were examined by scanning electron microscopy for changes in osteoblast length, orientation, ruffling, and overlap. As demonstrated previously, PTH caused the osteoblasts to elongate, align, and show fewer ruffles compared to controls. PTH increased PG synthesis by the stripped bones. Indomethacin inhibited PG formation but did not affect the osteoblast shape change. PGE2, indomethacin, or both drugs together had no discernible effect on any morphologic features. These findings indicate that PGE2 does not change osteoblast shape and that the cell shape change with PTH is not mediated by endogenous prostanoids.
Iliac bone biopsies at the time of periarticular stress fractures during fluoride therapy: Comparison with pretreatment biopsies
Authors: Schnitzler Christine M. , Mesquita Julia M. , Gear K. Ann , Robson Heather J. , Moodley Gopal P. , Smyth Amelia E.
Published: February 2010

We attempted to establish whether systemic changes in trabecular bone explain the development of stress fractures in the lower limbs during fluoride therapy for osteoporosis. To this end we compared transiliac bone biopsies obtained before treatment with those taken around the time of stress fractures after 14.3 ± 10.9 (SD) months of therapy in six patients (group A). Biopsies from a comparable group of six patients without stress fractures at the time of the second biopsy (after 11.9 ± 2.7 months of treatment) served for comparison (group B). The biopsies were processed undecalcified and examined by routine histomorphometry. The second biopsies did not show any significant improvement in mean bone volume or trabecular architecture. Although the second biopsies in group A had increased erosion surfaces (p < 0.05) and greater osteoid volume (p < 0.05), group B biopsies showed no difference in erosion surfaces but an increase in all osteoid parameters: osteoid volume (p < 0.05), osteoid surface (p < 0.05), and osteoid seam thickness (p < 0.01). We reached the following conclusions: (1) the combination of increased erosion and replacement of removed bone by as yet unmineralized osteoid in the stress fracture group must have weakened bone and allowed the development of stress fractures. (2) Stress fracture patients may have mounted a less vigorous osteoblast response to fluoride than non-stress fracture patients. Under these conditions microfractures are likely to heal poorly and propagate to develop into full stress fractures. (3) Renal failure is a contraindication to fluoride therapy
Effect of theophylline on calcium metabolism and circulating vitamin D metabolites
Authors: CPT Fortenbery Edwin J. , Mcdermott Michael T. , Duncan William E.
Published: February 2010

Theophylline has been shown to induce the hepatic microsomal enzyme system. These same enzymes increase the metabolism of vitamin D and 25-hydroxyvitamin D when induced by chronic barbiturate or phenytoin administration. To assess the long-term effects of theophylline on vitamin D and calcium metabolism, young rats were treated for 4 weeks with constant subcutaneous theophylline infusions. Theophylline-treated animals had a significantly increased urinary calcium excretion (p <0.0001), a significantly decreased total body calcium per gram body weight (p <0.05), and significantly decreased serum 25-hydroxyvitamin D concentrations (p <0.002) when compared to control animals. These alterations in the concentration of 25-hydroxyvitamin D may impair the ability to increase 1,25-dihydroxyvitamin D-dependent intestinal calcium absorption to compensate for excessive urinary calcium losses. These data suggest that theophylline promotes skeletal calcium loss, and its use may be a risk factor for the development of osteopenia in humans.
Effect of parathyroidectomy on aluminum toxicity and azotemic bone disease in the rat
Authors: Rodriguez Mariano , Lorenzo Victor , Felsenfeld Arnold J. , Llach Francisco
Published: February 2010

In maintenance dialysis patients, low-turnover osteomalacia and aplastic bone disease are generally attributed to aluminum toxicity. Both groups of patients have a relative deficiency of PTH. The reason for the development of osteomalacia versus aplastic bone disease is unclear. The present study was performed to evaluate whether parathyroidectomy (PTX) modifies the effect of aluminum administration on bone histology in renal failure. Seven groups of pair-fed rats were studied: normals (N); renal failure (RF); RF + PTX; PTX; RF + aluminum (AL); RF + PTX + AL; and PTX + AL. Aluminum was administered intraperitoneally 5 days/week for 6 weeks. All groups were sacrificed at 6 weeks. Renal failure increased the serum calcium in both the parathyroid intact (RF versus N, 11 + 0.1 versus 10 + 0.3 mg/dl, X + SEM, P < 0.05) and calcium-supplemented PTX groups (PTX + RF versus PTX, 9.7 + 0.2 versus 9.2 + 0.2 mg/dl, P <0.05). After PTX, aluminum administration increased the serum calcium (PTX + AL versus PTX, 9.8 + 0.3 versus 9.2 + 0.2, P < 0.05, and PTX + RF + AL versus PTX + RF, 10.8 + 0.1 versus 9.7 + 0.2 mg/dl, P < 0.05). In rats with renal failure receiving aluminum, PTX decreased osteoid volume and surface but not osteoid thickness. Rats receiving aluminum did not mineralize bone. Additionally, in PTX rats receiving aluminum, renal failure per se increased osteoblast surface, osteoid surface, osteoid volume, and osteoclast number. In conclusion, (1) aluminum administration in the absence of PTH produced a bone disease that resembled aplastic bone disease, (2) both renal failure and aluminum administration independently increased the serum calcium concentration, and (3) in aluminum-loaded rats, the presence of renal failure independent of PTH resulted in an increase in cellular activity and osteoid deposition.
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

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

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

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 < 0.05) and 32P-labeled lysophosphatidylinositol by 38% (p < 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 < 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

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 < 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 < 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

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

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

Magnetic 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

Tenocyte 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

Biomaterial‐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

Treatment 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

The 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

A 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

We 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

Hydrophilic 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.
Study of synthesised ecofriendly and biodegradable esters: fire resistance and lubricating properties
Authors: Nagendramma Ponnekanti , Kaul Savita , Bisht R. P. S.
Published: February 2010

Biodegradable esters have been synthesised using Polyols such as 2‐methyl‐2‐n‐propyl 1,3‐propane diol, 2,2‐di methyl 1,3‐propane diol, 1,1,1‐[tris] hydroxyl methyl propane, 1,1,1‐[tris] hydroxyl methyl ethane and carboxylic acids (C6‐C12) both pure and their mixtures with indigenous ion exchange resin (Indion‐130) catalyst. The products were characterised for their physico‐chemical properties and were evaluated for their lubrication performance. These were then compared with VG‐22 grade fire resistant hydraulic fluids (FRHFs).The products were found to have good potential for use as a base stock for formulations as FRHF of VG‐22 grade. Copyright © 2010 John Wiley & Sons, Ltd.
Poly(PEGDMA‐MAA) copolymeric micro and nanoparticles for oral insulin delivery
Authors: Tomar Lomas K. , Tyagi Charu , Lahiri Sitanshu S. , Singh Harpal
Published: February 2010

Poly(ethylene glycol) dimethacrylate (PEGDMA) and methacrylic acid (MAA) based micro and nanoparticles were prepared and evaluated as a carrier for oral delivery of insulin. PEGDMA was synthesized by esterification reaction of the PEG4000 with MAA in the presence of an acid catalyst. Particles of different size were prepared by emulsion polymerization reaction using different concentration of sodium lauryl sulphate (SLS) as an emulsifying agent. Synthesized copolymeric particle were characterized by attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FTIR), scanning electron microscopy, and acid value. The mean particle diameter of the polymeric micro and nanoparticles at various physiologically relevant pH values was measured using dynamic light scattering. Insulin loading efficiency of the particles was found to be directly proportional to the particle size and inversely proportional to the acid value of the particles. In vitro insulin release studies from various insulin loaded particles were performed by simulating the gastrointestinal tract conditions using HPLC. At pH 2.5, the release of insulin from polymeric particles was observed in the range of 5–8% while a significant higher release (20–35%) was observed at pH 7.4 during first 15 min of in vitro release. Largest size copolymeric particles of 8.3 µm also showed the highest efficiency to reduce the blood glucose level in diabetic rabbits. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and properties of new aromatic copolyesters containing phosphorous cyclic bulky groups
Authors: Vlad‐Bubulac Tachita , Hamciuc Corneliu
Published: February 2010

A series of phosphorus‐containing copolyesters was prepared by polycondensation of 2‐(6‐oxido‐6H‐dibenz<1,2>oxaphosphorin‐6‐yl)‐1,4‐naphthalene diol, 1, or of an equimolecular amount of 1 and different bisphenols 2, such as 4,4′‐isopropylidenediphenol, 4,4′‐(hexafluoroisopropylidene)diphenol and 2,7‐dihydroxynaphthalene, with an aromatic diacid chloride containing two preformed ester groups 3, namely, terephthaloyl‐bis‐(4‐oxybenzoyl‐chloride). The copolyesters exhibited good thermal stability having the temperature of 5% weight loss above 380°C and char yield at 700°C in the range of 20–31.2%. The glass transition temperature was in the range of 136–147°C. The polymers exhibited thermotropic liquid crystalline behavior, as was observed with polarized optical microscopy, differential scanning calorimetry, and X‐ray experiments. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers
SYSTAT
Authors: Wilkinson Leland
Published: February 2010

SYSTAT is a general‐purpose statistics package originally developed by Leland Wilkinson and now owned and developed by Cranes Software International, Bangalore, India. Its distinguishing features are a terse scripting language, a simple graphical user interface, a small footprint, accurate algorithms, and a comprehensive statistical graphics engine. Over the last 20 years, SYSTAT has had implementations of CP/M, DOS, Windows, Unix, and Macintosh operating systems. Copyright © 2010 John Wiley & Sons, Inc.

This article is categorized under:

Software for Computational Statistics > Software/Statistical Software
Effects of the Auxiliary Ligands on the Structures of Diphenate Complexes: From 1D Helical Chain to 2D Network
Authors: Gou Lei , Li Li , Li Jian‐Li , Fan Xiao‐Yong , Li Dong‐Lin
Published: February 2010

Two coordination polymers, [Cd(dpa)(L1)] (1) and [Cd(dpa)(L2)]·CH3CH2OH3 (2) (L1 = 2,6‐bis(1H‐benzimidazol‐2yl)‐pyridine, L2 = 2,2′‐(1,4‐butanediyl) bis (1H‐ benzimidazole) (L2), both of which contain helical chain subunits, were synthesized by the reaction of CdII salts and diphenic acid (H2dpa) with rigid, chelating and flexible, bridging auxiliary ligands, respectively. Compound 1 has a 1D helical chain structure, in which dpa2– as bridging ligand is responsible for the formation of the main framework and L1 as chelating ligand grafts on one side of the helical chain. This structure is further extended into a 3D supramolecular framework through two kinds of strong hydrogen bonding interactions. Compound 2 has a 2D structure, in which dpa2– bridges the CdII atoms into helical chains and L2 bridges the left‐ and right‐handed chains into a racemic layer with a [4,4] topology.
Scaled Quantum Mechanical Force Fields for the Peroxynitrates. II. Fluorocarbonyl Peroxynitrate and Chlorocarbonyl Peroxynitrate.
Authors: Coronel Angelina C. , Fernández Lis E. , Varetti Eduardo L.
Published: February 2010

The vibrational properties of fluorocarbonyl peroxynitrate, FC(O)OONO2 and chlorocarbonyl peroxynitrate, ClC(O)OONO2 were studied by means of density functional theory (DFT) methods. The obtained results served to revise the reported experimental spectra and their corresponding assignments. Subsequently, the revised data were used in the definition of scaled quantum mechanics (SQM) force fields for these peroxynitrates. A set of internal force constants was also calculated from such force fields.
Choice of Management of Southern Chinese BRCA Mutation Carriers
Authors: Kwong Ava , Wong Connie H. N. , Shea Catherine , Suen Dacita T. K. , Choi Catherine L. Y.
Published: February 2010

Background

Mutations in the BRCA genes confer greater risk of developing breast, ovarian, and prostate cancer. Families carrying the mutation can have intensive surveillance and take preventative measures. This is the first report on the uptake of such interventions in Chinese mutation carriers residing in Asia.

Methods

Breast and ovarian cancer index patients and family members referred for genetic counselling and testing who are found to carry the BRCA mutations were included in this multicenter study.

Results

A total of 31 patients with breast and/or ovarian cancer were found to carry BRCA1 or BRCA2 mutations. Forty‐one tested family members also carried the mutations. Of the females, 85.7% of the index patients opted for breast surveillance and 23.8% for prophylactic mastectomy. Of the family members, 82.4% chose breast surveillance and 17.7% had prophylactic mastectomy. The majority of index patients and family members preferred ovarian surveillance (84 and 82.4%). Amongst the index patients, 32% decided for prophylactic salpingo‐oophorectomy; 17.6% of the family members who did not have history of ovarian cancer decided to have prophylactic salpingo‐oophorectomy. All male index patients agreed to breast and prostate surveillance, including breast clinical examination and PSA monitoring. For those male family members found to be BRCA mutation carriers, 56.3% agreed to have breast surveillance and 66.7% agreed to have prostate surveillance. No index patient or family member agreed to any form of chemoprevention.

Conclusions

Chinese BRCA mutation carriers have a higher uptake of cancer surveillance than prophylactic surgery and have a lack of interest in the use of chemoprevention drugs.
A Randomized Controlled Trial of Intraarticular Ropivacaine for Pain Management Immediately following Total Knee Arthroplasty
Authors: Rosen Adam S. , Colwell Clifford W. , Pulido Pamela A. , Chaffee Tricia L. , Copp Steven N.
Published: February 2010

Total knee arthroplasty (TKA) is a commonly performed procedure for the treatment of end-stage arthritis of the knee. Pain control following TKA is difficult to manage in some patients. We examined the use of a postoperative intraarticular injection of 100 mL of 0.2% (200 mg) ropivacaine in a double-blind, prospective, placebo-controlled pilot study to evaluate its use as a pain control modality. All patients received general anesthesia. Postoperatively, patients were placed on intravenous patient-controlled analgesia with morphine. The ropivacaine group showed an early trend in lower visual analog scale (VAS) scores when compared with the placebo group. Patients receiving ropivacaine used a similar amount of narcotics compared with the placebo group. Intraarticular ropivacaine used for pain control after TKA demonstrated no statistically significant difference in lowering VAS scores or narcotic usage; therefore, intraarticular ropivacaine as a single modality is not recommended for effective pain management.
Le principe de l’anonymat du donneur de gamètes à l’épreuve de son contexte. Analyse des conceptions juridiques de l’identité
Authors: Brunet L.
Published: February 2010

L’ambition de cette étude est de proposer une lecture juridique qui puisse éclairer le débat passionné que suscite aujourd’hui le principe de l’anonymat des donneurs de gamètes. Ce principe, qui n’avait pas été remis en question depuis 1994, est en effet dénoncé par certains enfants nés d’une procréation médicalement assistée avec donneur et qui sont maintenant en âge de se manifester. L’impact de leur témoignage a été immédiatement sensible, et il a ainsi été proposé dans certains rapports officiels de lever l’anonymat sous certaines conditions. Pour comprendre comment le débat public s’est inversé de la sorte, il faut resituer la question de l’anonymat des donneurs de gamètes dans le prolongement d’évolutions moins visibles qui se sont manifestées dans le domaine du droit. En effet, les notions juridiques de filiation et d’identité ont été profondément reconfigurées avec le temps, et ces changements pèsent de tout leur poids dans le dossier de l’anonymat des donneurs de gamètes. Là où, hier, le droit se préoccupait de l’identification des individus à des fins politiques et sociales, aujourd’hui, il se soucie du sentiment d’identité de la personne et de son épanouissement personnel. Il faut prendre la mesure de ce changement survenu sous l’effet de l’orientation individualiste et égalitariste de la société. Le facteur déclenchant a été l’introduction de la preuve biologique dans le cadre des procès relatifs à la filiation. Mais l’attrait pour la vérité biologique, qui s’est répandue dans le droit de la filiation, s’est heurté à des situations volontairement construites sur le secret de l’ascendance biologique. La France admet en effet, depuis longtemps, qu’une femme puisse accoucher sans dévoiler son identité. L’impasse a été surmontée en dégageant une nouvelle notion juridique, celle d’origine personnelle. La loi permet aujourd’hui aux enfants nés sous X, dans certaines conditions, de demander l’identité de leur génitrice, sans que la connaissance de leur origine puisse affecter leur statut familial. La carrière de la notion d’origine personnelle prospère avec éclat sur la scène européenne et vient ainsi aiguiser le débat. Il est désormais reconnu, en droit interne comme en droit européen, que l’individu doit bénéficier d’un accès privilégié à ses origines personnelles. Le principe de l’anonymat des donneurs de gamètes peut-il rester à l’abri d’une telle (r)évolution ?
Web graph similarity for anomaly detection
Authors: Papadimitriou Panagiotis , Dasdan Ali , Garcia-Molina Hector
Published: February 2010

Web graphs are approximate snapshots of the web, created by search engines. They are essential to monitor the evolution of the web and to compute global properties like PageRank values of web pages. Their continuous monitoring requires a notion of graph similarity to help measure the amount and significance of changes in the evolving web. As a result, these measurements provide means to validate how well search engines acquire content from the web. In this paper, we propose five similarity schemes: three of them we adapted from existing graph similarity measures, and two we adapted from well-known document and vector similarity methods (namely, the shingling method and random projection based method). We empirically evaluate and compare all five schemes using a sequence of web graphs from Yahoo!, and study if the schemes can identify anomalies that may occur due to hardware or other problems.
Special commentary on the issue of reinfibulation
Authors: Cook Rebecca J. , Dickens Bernard M.
Published: February 2010

Policy on reinfibulation exposes the interface between individual or micro‐ethics and population‐wide or macro‐ethics. If, following childbirth, an infibulated woman requests reinfibulation, a gynecologist may respectfully advise her of its negative implications, but would not act in breach of ethical or usually legal requirements in undertaking the procedure. However, as a matter of health policy and professional responsibility, physicians should refuse to initiate infibulation, and advise their patients and communities that the procedure is harmful, not required by religious or other ordinance, and frequently if not always unlawful. Reinfibulation is not genital cutting (or “mutilation”) in itself, but when undertaken by a physician may appear to condone infibulation. This is contrary to medical professional ethics, which condemn medicalization of infibulation and generally of reinfibulation, even as a harm‐reduction strategy to spare women the risks of injury and infection from unskilled interventions.
Reproductive incompatibility among genetic groups of Bemisia tabaci supports the proposition that the whitefly is a cryptic species complex
Authors: Xu J. , De Barro P.J. , Liu S.S.
Published: February 2010

The worldwide distribution and extensive genetic diversity of the whitefly Bemisia tabaci has long been recognized. However, whether B. tabaci is a complex species or a species complex has been a subject of debate. Recent phylogenetic analyses suggest that B. tabaci is a cryptic species complex composed of at least 24 morphologically indistinguishable species. Here, we conducted crossing experiments and demonstrated reproductive incompatibility among three of the 24 putative species. Our data and those of previously reported crossing experiments among various putative species of B. tabaci were collated to reveal the pattern of reproductive isolation. The combined results provide strong support to the proposition that B. tabaci is a cryptic species complex.
Mission from Below: Captive Women and Conversion on the East Roman Frontiers
Authors: Sterk Andrea
Published: February 2010

The significance of captives in the history of empire has come to the fore in several recent books and articles. Linda Colley starts her intriguing study of this theme with the stories of two famous, if legendary, British captives—Robinson Crusoe and Gulliver—explaining how each represents a different conception of empire: the former a shipwrecked ex-slave turned conqueror and colonizer; the latter an overseas adventurer who is captured, humiliated, and terrorized but ultimately transformed by the values of his captors into a critic of his own society. Far from the heroes of Defoe and Swift, female captives featured in conversion accounts on the east Roman frontiers represent another response to captivity in a very different imperial world—that of the Roman and Iranian empires of late antiquity. These protagonists neither came to dominate the kingdoms in which they were held nor assimilated the culture of their captors but maintained their identity, their customs, and their religion in captivity. Indeed, these captives went further still, actually transforming the peoples and governments under which they were held from their very positions of subordination.
The Waters of Rebirth: The Eighteenth Century and Transoceanic Protestant Christianity
Authors: Roeber A. G.
Published: February 2010

In a provocatively titled 2005 book, Mark Noll and Carolyn Nystrom wonderedIs the Reformation Over?While not presuming to answer their query, the present essay argues that a self-understanding of European Protestants inherited from the Reformation had to die in the 1740s in the process of giving birth to the rapidly spreading version of western Christianity that became known as evangelicalism. Protestants, of both the radical and magisterial sort had cherished since the sixteenth century a sense of themselves as the true, ancient, and apostolic church. The Reformation, however, in its theological, as well as its socio-political and economic dimensions, had long “left its heirs no settled comprehensive system, only with many unresolved questions of principle and usage, not least in decisions relating to the body.”