bluuebunny/crossref_metadata_2025_split huggingface dataset:
Practical Operationalizations of Risk Factors for Fracture in Older Women: Results From Two Longitudinal Studies
Authors: Pluijm Saskia MF , Steyerberg Ewout W , Kuchuk Natalia O , Rivadeneira Fernando F , Looman Caspar W , Van Schoor Natasja M , Koes Bart , Mackenbach Johan P , Lips Paul , Pols Huibert A 
Published: July 2008

Abstract
Several guidelines on osteoporosis have proposed algorithms to identify persons at high risk of fractures. Although these algorithms include well-known risk factors, it is not clear how they can best be operationalized for use in general practice. The aim of this study was to compare the predictive performance of different operationalizations of four categories of risk factors for fractures that can be used in general practice. This study included 4157 women of ≥60 yr of age (mean ± SD: 74.1 ± 9.1 yr) with a median follow-up of 8.9 yr of the Rotterdam Study and 762 women of ≥65 yr of age (mean ± SD: 76.0 ± 6.7.yr) with a median follow-up of 6.0 yr of the Longitudinal Aging Study Amsterdam (LASA). At baseline, information on four categories of risk factors was obtained, including (1) family history of hip fractures, (2) type of prior fractures, (3) low body weight/body mass index (BMI), and (4) mobility impairment. The occurrence of fragility fractures, including hip, pelvic, humerus, and wrist fractures, was used as outcome measure. We quantified the predictive performance of each risk factor by a χ2 statistic, calculated as the difference in –2 Log likelihood attributable to the risk factor, with adjustment for age and other risk factors. In the Rotterdam Study, 399 fragility fractures occurred during 31,472 person-years (PY) of follow-up. In this study, any prior fracture in the past 5 yr (χ2 = 6; p = 0.02), body weight &lt; 64 kg (versus ≥64 kg; χ2 = 6.7; p = 0.01), BMI &lt; 22 kg/m2 (versus ≥22 kg/m2; χ2 = 8.7; p = 0.003), and use of a walking aid (χ2 = 7.5; p = 0.004) were the most practical operationalizations of the risk factor categories, after adjustment for age and other risk factors. In LASA, 52 fragility fractures occurred during 3935 PY of follow-up. Associations were similar as in the Rotterdam Study, except that low body weight and BMI were not associated with fragility fracture. None of the usual operationalizations of family history of hip fractures was independently associated with fragility fracture in either study. Prior osteoporotic fracture, body weight &lt;64 kg, a BMI &lt;22 kg/m2, and the use of a walking aid are practical operationalizations of risk factors for fragility fractures. On the basis of the results of this study, a simple, practical algorithm can be developed for use in general practice.
Granulocyte Colony-Stimulating Factor Induces Osteoblast Apoptosis and Inhibits Osteoblast Differentiation
Authors: Christopher Matthew J , Link Daniel C 
Published: July 2008

Abstract
Long-term treatment of mice or humans with granulocyte colony-stimulating factor (G-CSF) is associated with a clinically significant osteopenia characterized by increased osteoclast activity and number. In addition, recent reports have observed a decrease in number of mature osteoblasts during G-CSF administration. However, neither the extent of G-CSF's suppressive effect on the osteoblast compartment nor its mechanisms are well understood. Herein, we show that short-term G-CSF treatment in mice leads to decreased numbers of endosteal and trabecular osteoblasts. The effect is specific to mature osteoblasts, because bone-lining cells, osteocytes, and periosteal osteoblasts are unaffected. G-CSF treatment accelerates osteoblast turnover in the bone marrow by inducing osteoblast apoptosis. In addition, whereas G-CSF treatment sharply increases osteoprogenitor number, differentiation of mature osteoblasts is impaired. Bone marrow transplantation studies show that G-CSF acts through a hematopoietic intermediary to suppress osteoblasts. Finally, G-CSF treatment, through suppression of mature osteoblasts, also leads to a marked decrease in osteoprotegerin expression in the bone marrow, whereas expression of RANKL remains relatively constant, suggesting a novel mechanism contributing to the increased osteoclastogenesis seen with long-term G-CSF treatment. In sum, these findings suggest that the hematopoietic system may play a novel role in regulating osteoblast differentiation and apoptosis during G-CSF treatment.
Bone Resorption Inhibitor Alendronate Normalizes the Reduced Bone Thickness of TRPV5−/− Mice
Authors: Nijenhuis Tom , van der Eerden Bram CJ , Hoenderop Joost GJ , Weinans Harrie , van Leeuwen Johannes PTM , Bindels René JM 
Published: July 2008

Abstract
TRPV5 is a Ca2+-selective channel involved in transcellular Ca2+ absorption expressed in kidney and in the ruffled border of osteoclasts. Studies in hypercalciuric TRPV5 knockout (TRPV5−/−) mice, which display significantly increased vitamin D levels, showed that TRPV5 ablation increases number and size of osteoclasts but impairs osteoclast-mediated bone resorption. The latter is not in line with the observed decreased bone thickness in TRPV5−/− mice. Bisphosphonates also inhibit osteoclast-mediated bone resorption. The aim of this study was to evaluate the effect of alendronate on the expression of the Ca2+ transporters in bone, kidney, and duodenum and, importantly, the bone phenotype in TRPV5−/− mice. Wildtype (TRPV5+/+) and TRPV5−/− mice were treated during 10 wk with 2 mg/kg alendronate or vehicle weekly and housed in metabolic cages at the end of treatment. Urine and blood samples were taken for biochemical analysis, and duodenum, kidney, and femur were sampled. Expression of Ca2+ transporters and osteoclast ruffled border transporters in bone and cultured osteoclasts was determined by QPCR analysis. Femurs were scanned using μCT, and resorption pit assays were performed in bone marrow cultures isolated from TRPV5+/+ and TRPV5−/− mice. Alendronate treatment enhanced bone thickness in TRPV5+/+ mice but also normalized the disturbed bone morphometry parameters in TRPV5−/− mice. Bone TRPV5 expression was specifically enhanced by alendronate, whereas the expression of Ca2+ transporters in kidney and intestine was not altered. The expression of the osteoclast ruffled border membrane proteins chloride channel 7 (CLC-7) and the vacuolar H+-ATPase did not differ between both genotypes, but alendronate significantly enhanced the expression and PTH levels in TRPV5−/− mice. The expression of TRPV5, CLC-7, and H+-ATPase in osteoclast cultures was not affected by alendronate. The number of resorption pits was reduced in TRPV5−/− bone marrow cultures, but the response to vitamin D was similar to that in TRPV5+/+ cultures. The alendronate-induced upregulation of TRPV5 in bone together with the decreased resorptive capacity of TRPV5−/− osteoclasts in vitro suggests that TRPV5 has an important role in osteoclast function. However, our data indicate that significant bone resorption still occurs in TRPV5−/− mice, because alendronate treatment normalized bone thickness in these mice. Thus, TRPV5−/− mice are able to rescue the resulting defect in osteoclast-mediated bone resorption, possibly mediated by the long-term hypervitaminosis D or other (non)hormonal compensatory mechanisms.
Vitamin D Depletion Induces RANKL-Mediated Osteoclastogenesis and Bone Loss in a Rodent Model
Authors: Anderson Paul H , Sawyer Rebecca K , Moore Alison J , May Brian K , O'Loughlin Peter D , Morris Howard A 
Published: July 2008

Abstract
The association between increased risk of hip fracture and low vitamin D status has long been recognized. However, the level of vitamin D required to maintain bone strength is controversial. We used a rodent model of vitamin D depletion to quantify the 25-hydroxyvitamin D (25D) levels required for normal mineralization. Six groups of 10-wk-old male Sprague-Dawley rats (n = 42) were fed a diet containing 0.4% calcium and various levels of dietary vitamin D3 for 4 mo to achieve stable mean serum 25D levels ranging between 10 and 115 nM. At 7 mo of age, animals were killed, and the histomorphometry of distal and proximal femora and L2 vertebra was analyzed. Total RNA was extracted from whole femora for real-time RT-PCR analyses. In the distal femoral metaphysis, trabecular bone mineral volume (BV/TV) showed a significant positive association with circulating 25D levels (r2 = 0.42, p &lt; 0.01) in the animals with serum 25D levels between 20 and 115 nM. Osteoclast surface (Oc.S) levels were positively associated with RANKL:OPG mRNA ratio, higher in groups with lower serum 25D levels, and were independent of serum 1,25D levels. Serum 25D levels &lt;80 nM gave rise to osteopenia as a result of increased osteoclastogenesis, suggesting that levels of 25D &gt;80 nM are needed for optimal bone volume. These data indicate that serum 25D levels are a major determinant of osteoclastogenesis and bone mineral volume and are consistent with the levels of 25D recommended to reduce the risk of fracture in humans.
Diagnostic performance of rapid tests for detection of fecal calprotectin and lactoferrin and their ability to discriminate inflammatory from irritable bowel syndrome
Authors: Otten Charlotte M.T. , Kok Liselotte , Witteman Ben J.M. , Baumgarten Ruben , Kampman Ellen , Moons Karel G.M. , de Wit Niek J. 
Published: July 2008

Abstract: Ruling out somatic bowel disease, such as inflammatory bowel disease (IBD), is an important goal in the management of abdominal complaints. Endoscopy is commonly used but is invasive and expensive. Mucosal inflammation in IBD can be detected through fecal biomarkers, though the present enzyme-linked immunoabsorbent assay (ELISA) tests require laboratory facilities. We validated the diagnostic performance of two new fecal rapid tests (FRTs) for the detection of calprotectin and lactoferrin and assessed their potential to differentiate IBD from irritable bowel syndrome (IBS).: The calprotectin and lactoferrin FRTs and ELISA tests were performed on the fecal samples of 114 patients referred for endoscopy, 80% of whom had IBS and 20% IBD, and validated against the endoscopic diagnosis.: The sensitivity and negative predictive value of the calprotectin FRT were both 100%, whereas they were 78% and 95%, respectively, for the lactoferrin FRT. The specificity and positive predictive value were slightly higher for the lactoferrin FRT. Both FRTs had similar diagnostic accuracy as the corresponding ELISA tests.: The calprotectin and lactoferrin rapid tests are as good as the ELISA tests in detecting colonic inflammation. Given their simple use, FRTs can support the non-invasive exclusion of IBD, notably in primary care.Clin Chem Lab Med 2008;46:1275–80.
Fetal hemoglobin: assessment of glycation and acetylation status by electrospray ionization mass spectrometry
Authors: Davison Andrew S. , Green Brian N. , Roberts Norman B. 
Published: July 2008

Abstract: Electrospray ionization mass spectrometry (ESI-MS) can be used for the measurement of glycated adult hemoglobin. Here, we describe the evaluation of ESI-MS for measurement of glycated (GHbF) and acetylated (AcHbF) fetal hemoglobin and the identification by mass of different chains of fetal hemoglobin.: Blood samples were diluted in an acidic denaturing solvent, desalted with AG 50W-X8 resin and introduced directly into the mass spectrometer. Resulting mass spectra were processed to determine the percentage of GHbF and AcHbF and the γ-chain masses.: The procedure yielded reproducible quantitative assay of GHbF and AcHbF, with coefficients of variation <4.9%. Measurement of α-chain glycation was similarly reproducible and is suggested as an alternative marker of glycemic control. Marked increases in glycation occurred in dried spot blood samples, which were related to duration of storage, temperature and glucose concentration. Molecular masses of fetal hemoglobin chains were also determined and in 42 neonates studied, two types A and B were identified, two-thirds were type A with γ-chain masses corresponding to: ESI-MS can be used for the estimation of GHbF and AcHbF and the accurate measurement of fetal γ-chain masses. The use of whole blood is preferred for analysis.Clin Chem Lab Med 2008;46:1230–8.
Dietary factors associated with plasma high molecular weight and total adiponectin levels in apparently healthy women
Authors: Yannakoulia Mary , Yiannakouris Nikos , Melistas Labros , Fappa Evaggelia , Vidra Nikoletta , Kontogianni Meropi D , Mantzoros Christos S 
Published: July 2008

ObjectiveOur aim was to investigate associations between dietary factors and high molecular weight (HMW) as well as total adiponectin in a sample of apparently healthy adult Mediterranean women.Design and methodsTwo hundred and twenty women were enrolled in this study. Anthropometric and body composition measurements were performed in all subjects. Fasting blood samples were taken; HMW and total adiponectin concentrations were measured. Food intake was evaluated using 3-day food records. The frequency of consumption of several food groups was approximately quantified in terms of number of servings per day. Furthermore, dietary intakes of betaine, choline, and free choline were estimated.ResultsWomen in the highest HMW adiponectin tertile had higher fruit intake compared with those with lower levels, after adjusting for potential confounders (P=0.04). On the contrary, dietary betaine and choline intakes were not different among HMW adiponectin tertiles. In linear models, fruit consumption, controlling for biological and lifestyle variables, was significantly related to HMW adiponectin (partial r=0.15, P=0.04), but the association with total adiponectin did not reach statistical significance (partial r=0.11, P=0.12). A significant negative correlation between total adiponectin and refined cereals was also observed (partial r=−0.16, P=0.03).DiscussionThis is the first study that evaluates associations between dietary factors and HMW adiponectin levels. The associations found are moderate and indicate that, after multivariate adjustment, fruit consumption is related to HMW adiponectin in both linear and nonlinear models.
Evaluation of effluent toxicity as an indicator of aquatic life condition in effluent-dominated streams: A pilot study
Authors: Diamond Jerry , Stribling James , Bowersox Marcus , Latimer Henry 
Published: July 2008

Abstract
The types and quality of data needed to determine relationships between chronic whole effluent toxicity (WET) test results and in-stream biological condition were evaluated using information collected over a 1.5-y period from 6 different sites across the United States. A data-quality-objectives approach was used that included several proposed measurement quality objectives (MQOs) that specified desired precision, bias, and sensitivity of methods used. The 6 facilities used in this study (4 eastern and 2 western United States) all had design effluent concentrations &gt;60% of the stream flow. In addition to at least quarterly chronic Ceriodaphnia dubia, Pimephales promelas (fathead minnow), and Selenastrum capricornutum (green algae) WET tests, other tests were conducted to address MQOs, including splits, duplicates, and blind positive and negative controls. Macroinvertebrate, fish, and periphyton bioassessments were conducted at multiple locations upstream and downstream of each facility. The test acceptance criteria of the US Environmental Protection Agency (USEPA) were met for most WET tests; however, this study demonstrated the need to incorporate other MQOs (minimum and maximum percent significant difference and performance on blind samples) to ensure accurate interpretation of effluent toxicity. More false positives, higher toxicity, and more “failed” (noncompliant) tests were observed using no-observed-effect concentration (NOEC) as compared to the IC25 endpoint (concentration causing ≥25% decrease in organism response compared to controls). Algae tests often indicated the most effluent toxicity in this study; however, this test was most susceptible to false positives and high interlaboratory variability. Overall, WET test results exhibited few relationships with bioassessment results even when accounting for actual effluent dilution. In general, neither frequency of WET noncompliance nor magnitude of toxicity in tests were significantly related to differences in biological condition upstream and downstream of a discharge. Periphyton assessments were most able to discriminate small changes downstream of the effluent, followed by macroinvertebrates and fish. Although sampling methods were robust, more replicate samples collected upstream and downstream of each facility were needed to increase detection power. In general, macroinvertebrate and periphyton assessments together appeared to be sufficient to address project objectives.
Porphyromonas gingivalis Infection Accelerates Intimal Thickening in Iliac Arteries in a Balloon‐Injured Rabbit Model
Authors: Zhang Ming‐Zhu , Li Chao‐Lun , Jiang Yun‐Tao , Jiang Wei , Sun Ying , Shu Rong , Liang Jing‐Ping 
Published: July 2008

Background: Current epidemiologic data suggest that a localized infection (periodontitis) can disseminate into the distant tissues, and subgingival bacteria can migrate in the bloodstream, thereby contributing to independent systemic disease processes. To test this hypothesis, we investigated the effect of repeated systemic inoculations with Porphyromonas gingivalis (Pg) on intimal hyperplasia in iliac arteries in a rabbit model of balloon injury.Methods: One week after single balloon injury to the iliac artery, 30 male New Zealand rabbits were randomly assigned to intravenous inoculation with 100 μl live Pg (107 colony‐forming units; n = 15) or vehicle (n = 15) once weekly for 4, 8, or 12 consecutive weeks. Arteries were fixed by perfusion and removed for analysis of neointimal lesion formation. We measured intimal and medial lesion areas in iliac artery cross‐sections as well as the intimal/medial ratio (I/M). We also analyzed Pg 16S ribosomal DNA amplification with polymerase chain reaction, systemic proinflammatory mediators with enzyme‐linked immunosorbent assay, and immunolocalization of macrophages in the balloon‐injured arteries.Results: At 12 weeks, iliac intimal hyperplasia was accelerated, and I/M was significantly increased in Pg‐inoculated animals (I/M 3.961 ± 0.536 in the Pg group versus 3.585 ± 0.353 in the control animals; P <0.01). Pg‐inoculated animals also had significant increases in macrophage infiltration at 12 weeks, C‐reactive protein levels at all time points, and interleukin‐6 levels at 12 weeks. Moreover, Pg ribosomal DNA was found in the injured arteries of Pg‐inoculated animals, but only after 12 weeks.Conclusion: Long‐term systemic challenge with Pg, an oral pathogen, may accelerate intimal hyperplasia in balloon‐injured iliac arteries.
Periodontal Status of Patients With Dentin Dysplasia Type I: Report of Three Cases Within a Family
Authors: Da Rós Gonçalves Lorena , Oliveira Cristiana Aroeira G.R. , Holanda Rose , Silva‐Boghossian Carina M. , Colombo Ana Paula Vieira , Maia Lucianne Cople , Feres‐Filho Eduardo Jorge 
Published: July 2008

Background: Dentin dysplasia type I (DDI) is a rare hereditary disturbance of dentin formation. It is characterized by clinically normal–appearing crowns; obliteration of pulp chambers; and short, blunted and malformed roots that are commonly associated with periodontal attachment loss (PAL). In this context, we report three cases within a family with similar clinical and radiographic features of DDI but with differing microbiologic and periodontal conditions.Methods: A 42‐year‐old white female and her two daughters (25 and 10 years of age) presented with a diagnosis of DDI. Probing depth (PD), clinical attachment level (CAL), visible plaque, and bleeding on probing (BOP) were recorded. Subgingival biofilm samples were randomly collected and analyzed by checkerboard DNA‐DNA hybridization.Results: The mother presented 34.9% of sites with PD ≥4 mm, 41.3% of sites with CAL ≥4 mm, and 57% of sites with BOP; both daughters presented no sites with PD or CAL >3 mm and <10% of sites with BOP. Microbiologic analysis detected Gemella morbillorum, Neisseria mucosa, and Staphylococcus aureus in ≥50% of the mother's samples. The daughters showed high levels (>104 bacterial cells) of some periodontopathic bacteria, including members of the red (Porphyromonas gingivalis) and orange (Fusobacterium periodonticum and F. nucleatum polymorphum) complexes and beneficial species of the yellow (Streptococcus gordonii) and purple (Veillonella parvula) complexes. The mother presented high mean levels only for four tested species (N. mucosa, Prevotella melaninogenica, Treponema denticola, and V. parvula).Conclusion: A combination of radiographs, microbiologic analysis, and preventive professional monitoring care is important to avoid PAL and to provide oral health in patients with DDI.
A Comparative Analysis of Bone Formation Induced by Human Demineralized Freeze‐Dried Bone and Enamel Matrix Derivative in Rat Calvaria Critical‐Size Bone Defects
Authors: Intini Giuseppe , Andreana Sebastiano , Buhite Robert J. , Bobek Libuse A. 
Published: July 2008

Background: Human demineralized freeze‐dried bone allograft (DFDBA) and enamel matrix derivative (EMD) have been used with varying success for the treatment of bone and periodontal defects. The purpose of this study was to compare qualitatively and quantitatively the bone formation induced by DFDBA and EMD to that of a positive control, recombinant human bone morphogenetic protein 2 (rhBMP‐2), in the 8‐mm rat calvaria critical‐size bone defect.Methods: Five groups of five rats each were used. The two test groups were DFDBA and EMD. A negative control consisted of a defect without any biomaterial implanted, a positive control consisted of a defect filled with collagen carrying rhBMP‐2, and a non‐surgical control consisted of the intact rat calvaria. Eight weeks after implantation of the biomaterials, histologic analysis was used for qualitative assessments and microcomputed tomography was used for quantitative assessments of bone formation. Statistical evaluation was performed by analysis of variance followed by the Fisher's least significant difference multiple‐comparison test.Results: In the negative control and EMD groups, the histologic analysis showed no bone formation within the center of the defect and limited bone repair at its margins. In the DFDBA group, granules of DFDBA were still present 8 weeks after implantation, and a limited degree of osteoinduction was seen at the center of the defect. The microcomputed tomography quantitative analysis showed a limited capacity of DFDBA and EMD to induce bone formation, and no statistically significant difference was detected among DFDBA, EMD, and the negative control. On the contrary, the positive control (rhBMP‐2) consistently showed regeneration of bone throughout the critical‐size defects.Conclusion: Unlike rhBMP‐2, DFDBA and EMD had limited ability to induce bone formation in the rat calvaria critical‐size bone defect; therefore, they may not be effective as bone‐regenerative therapy for critical‐size defects.