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1

DISCOVERY AND RESEARCH ON JIAHU BONE FLUTES IN WUYANG, CHINA.  

SciTech Connect

The site of Jiahu is located in Jiahu village, Wuyang County, Henan province, on the Western edge of the broad plain of Huanhuaihai. On its north the site borders the Sha River, in the upper reaches of the Huai River; its latitude is 33{degree} 36 minutes North, longitude 113{degree} 40 minutes East, and it is 67.5 meters above sea level. Between 1983 and 1987, the Henan Cultural Relics and Archaeology Institute carried out six campaigns of excavation here, revealing an area of 2400 square meters. Except for the trial excavation in the spring of 1983, Zhang Juzhong has been in charge of all the excavations. In early May 1986, while excavating tomb 78, Zhang Juzhong and Yang Zhenwei first discovered two funerary bone flutes. They soon found other, similar bone flutes in tombs 73, 94 and 121 respectively. Mr. Zhang's attention was instantly focused on these remarkable finds. In the campaign of autumn 1986, one or two more bone flutes were discovered in each of tombs 233,273, 263 and 270. Finally, in the spring of 1987, again one or two bone flutes were found in each of the tombs 282, 363,341,411,344 and 387. Up to the end of excavation in June 1987, altogether 25 bone flutes had been found, of which 17 were complete or almost complete, 6 broken or fragmentary and 2 were half-finished examples. Among the 17 complete bone flutes, there were 14 having seven holes, one five-hole, one six-hole and one eight-hole bone flute. In particular, the bone flute M282:20 was exquisitely made, and complete. Zhang Juzhong, the discoverer of the bone flutes, researcher Pei Mingxiang, the. ex-director of the division, who came to the digging site to see the progress of the work, and their coworkers were all understandably very excited.

JUZHONG, Z.; HARBOTTLE, G.; XINGHUA, X.; CHANGSUI, W.

2000-11-01

2

Stability and Three-Dimensional Analysis of Bone Formation in Longitudinally Fluted Miniscrew Implants  

E-print Network

and potential failure of an orthodontic miniscrew. Conversely, a very high insertion placement torque places significant stresses on the surrounding bone leading to bone degradation or frictional necrosis.46 Another study places the validity of insertion... hardening by x-ray spectrum dispersion 2) photon starvation and poor signal to noise ratio 3) enhanced motion interference between the metal and adjacent structure caused by high contrast.60 Rebaudi et al in 2004 scanned a cylindrical biopsy...

Truong, An Van

2014-04-22

3

Dayton C. Miller Flute Collection  

NSDL National Science Digital Library

The online presentation of the Miller Flute Collection in the Music Division of the Library of Congress has images of over 1,500 instruments, as well as a 17th-century flageolet tutorial. There is also an impressive array of "Special Presentations", which vary from an explanation what constitutes a flute, in "Flute Misnomers" and "Fife vs. Band Flute" to "Books, Tutors and Patents", which has a link to the images of the book "The Pleasant Companion: Or New Lessons and Instructions for the Flagelet". In the "Understanding the Collection" section of the homepage, there is the "Catalog of the Wind Instruments in the Dayton C. Miller Collection", which helpfully offers "Conventions and Definitions", "Transverse Flute Elements Named in This Catalog" and "Key and Key Mounting Nomenclature" to help researchers and the public better understand the materials available in this great collection. The "Collection Connections" link, also in "Understanding the Collection", is a resource for teachers that, among other things, names the historical eras that are represented in the flute collection, and provides links to "Related Collections and Exhibits" on the American Memory website.

4

From Mozart to Lookout: the Flute’s Evolution from 1800  

Microsoft Academic Search

As this brief survey of the flute’s history and repertoire reveals, the instrument evolved significantly over the centuries. From works such as Mozart’s Concerto in G to Robert Dick’s Lookout, from the single-keyed, four-piece flute of Jacob Denner to the highly complex mechanism of Alexander Murray, the flute’s growth has been dramatic and extensive. While some of its technical changes

Anna J. Reisenweaver

2011-01-01

5

The impact of a modified cutting flute implant design on osseointegration.  

PubMed

Information concerning the effects of the implant cutting flute design on initial stability and its influence on osseointegration in vivo is limited. This study evaluated the early effects of implants with a specific cutting flute design placed in the sheep mandible. Forty-eight dental implants with two different macro-geometries (24 with a specific cutting flute design - Blossom group; 24 with a self-tapping design - DT group) were inserted into the mandibular bodies of six sheep; the maximum insertion torque was recorded. Samples were retrieved and processed for histomorphometric analysis after 3 and 6 weeks. The mean insertion torque was lower for Blossom implants (P<0.001). No differences in histomorphometric results were observed between the groups. At 3 weeks, P=0.58 for bone-to-implant contact (BIC) and P=0.52 for bone area fraction occupied (BAFO); at 6 weeks, P=0.55 for BIC and P=0.45 for BAFO. While no histomorphometric differences were observed, ground sections showed different healing patterns between the implants, with better peri-implant bone organization around those with the specific cutting flute design (Blossom group). Implants with the modified cutting flute design had a significantly reduced insertion torque compared to the DT implants with a traditional cutting thread, and resulted in a different healing pattern. PMID:24583140

Jimbo, R; Tovar, N; Marin, C; Teixeira, H S; Anchieta, R B; Silveira, L M; Janal, M N; Shibli, J A; Coelho, P G

2014-07-01

6

Finite Larmor radius flute mode theory with end loss  

SciTech Connect

The theory of flute mode stability is developed for a two-energy- component plasma partially terminated by a conducting limiter. The formalism is developed as a preliminary study of the effect of end-loss in open-ended mirror machines where large Larmor radius effects are important.

Kotelnikov, I.A. [AN SSSR, Novosibirsk (Russian Federation). Inst. Yadernoj Fiziki; Berk, H.L. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies

1993-08-01

7

Kristina Sorensen Acoustics of a Rotating Grand Piano & the Flute  

E-print Network

Kristina Sorensen Acoustics of a Rotating Grand Piano & the Flute Kristina Sorensen 1 10 June 2011 will be utilizing an acoustical array of microphones to analyze the three-dimensional sound radiation. Computer Relationships of Sound Propagation in both the Frequency and Time Domains Improve Competence in Acoustical

Hart, Gus

8

Compression Behavior of Fluted-Core Composite Panels  

NASA Technical Reports Server (NTRS)

In recent years, fiber-reinforced composites have become more accepted for aerospace applications. Specifically, during NASA s recent efforts to develop new launch vehicles, composite materials were considered and baselined for a number of structures. Because of mass and stiffness requirements, sandwich composites are often selected for many applications. However, there are a number of manufacturing and in-service concerns associated with traditional honeycomb-core sandwich composites that in certain instances may be alleviated through the use of other core materials or construction methods. Fluted-core, which consists of integral angled web members with structural radius fillers spaced between laminate face sheets, is one such construction alternative and is considered herein. Two different fluted-core designs were considered: a subscale design and a full-scale design sized for a heavy-lift-launch-vehicle interstage. In particular, axial compression of fluted-core composites was evaluated with experiments and finite-element analyses (FEA); axial compression is the primary loading condition in dry launch-vehicle barrel sections. Detailed finite-element models were developed to represent all components of the fluted-core construction, and geometrically nonlinear analyses were conducted to predict both buckling and material failures. Good agreement was obtained between test data and analyses, for both local buckling and ultimate material failure. Though the local buckling events are not catastrophic, the resulting deformations contribute to material failures. Consequently, an important observation is that the material failure loads and modes would not be captured by either linear analyses or nonlinear smeared-shell analyses. Compression-after-impact (CAI) performance of fluted core composites was also investigated by experimentally testing samples impacted with 6 ft.-lb. impact energies. It was found that such impacts reduced the ultimate load carrying capability by approximately 40% on the subscale test articles and by less than 20% on the full-scale test articles. Nondestructive inspection of the damage zones indicated that the detectable damage was limited to no more than one flute on either side of any given impact. More study is needed, but this may indicate that an inherent damage-arrest capability of fluted core could provide benefits over traditional sandwich designs in certain weight-critical applications.

Schultz, Marc R.; Oremont, Leonard; Guzman, J. Carlos; McCarville, Douglas; Rose, Cheryl A.; Hilburger, Mark W.

2011-01-01

9

Williams College Department of Music Flute Studio Recital  

E-print Network

Williams College Department of Music Flute Studio Recital Students of Floyd Hebert Georges Enescu:00 noon I/O Festival of New Music ­ Out of the Box Williams College Museum of Art 1/11 8:00pm I/O Festival Williams College Museum of Art 2/7 8:00pm Williams Chamber Players Brooks-Rogers Recital Hall 2/12 7:00pm

Aalberts, Daniel P.

10

Life history of the fluted kidneyshell ptychobranchus subtentum  

USGS Publications Warehouse

The fluted kidneyshell Ptychobranchus subtentum (Say, 1825) is a candidate for listing under the Endangered Species Act by the US Fish and Wildlife Service. Fecundity, fish hosts, and selected population demographics were determined during 20052006 for the fluted kidneyshell in the upper Clinch River, Hancock County, Tennessee. Females were fertilized in Aug. within a 5 d period and contained viable glochidia about 4 wk later. As the embryos began to develop, the marsupium gradually changed color from white to dark brown. Glochidia were contained within conglutinates that resemble Simuliidae pupae likely to attract benthic insectivorous fish and were held over winter and released in May. Fecundity was positively related to mussel length (r 2 = 0.81) and ranged from 43,000 to 500,000 glochidia. Eight species of darters (Etheostoma spp. and Percina spp.) were infested with glochidia in the laboratory to examine potential hosts and host suitability. Juveniles transformed on bluebreast darters E. camurum and dusky darters P. sciera and previously reported hosts: rainbow darters E. caeruleum and fantail darters E. flabellare. In addition, fantail darters and rainbow darters were infested with glochidia from two river systems. The median time of glochidial metamorphosis did not differ significantly between the two mussel populations. The observed ratio of adult females to males (1.9:1) in the Clinch River differed significantly from 1:1. Based upon thin-sections, individuals live to at least 26 y and females become sexually mature at age five. ?? 2012, American Midland Naturalist.

Davis, V.M.; Layzer, J.B.

2012-01-01

11

FLUTE: A versatile linac-based THz source  

SciTech Connect

A new compact versatile linear accelerator named FLUTE is currently being designed at the Karlsruhe Institute of Technology. This paper presents the status of this 42 MeV machine. It will be used to generate strong (several 100 MV/m) ultra-short ({approx}1 ps) THz pulses (up to {approx}4-25 THz) for photon science experiments, as well as to conduct a variety of accelerator studies. The latter range from comparing different coherent THz radiation generation schemes to compressing electron bunches and studying the electron beam stability. The bunch charge will cover a wide range ({approx}100 pC-3 nC). Later we plan to also produce ultra-short x-ray pulses from the electron bunches, which, for example, could then be combined for THz pump-x-ray probe experiments.

Nasse, M. J.; Schuh, M.; Schwarz, M. [Laboratory for Applications of Synchrotron Radiation (LAS), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe (Germany); Naknaimueang, S.; Mathis, Y.-L.; Rossmanith, R.; Wesolowski, P.; Huttel, E. [ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Plech, A. [Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Schmelling, M. [Max Planck Institute for Nuclear Physics (MPIK), 69117 Heidelberg (Germany); Mueller, A.-S. [Laboratory for Applications of Synchrotron Radiation (LAS), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe (Germany); ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany)

2013-02-15

12

78 FR 25041 - Endangered and Threatened Wildlife and Plants; Endangered Status for the Fluted Kidneyshell and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF THE INTERIOR Fish and Wildlife Service 50 CFR...Wildlife and Plants; Endangered Status for the Fluted Kidneyshell and Slabside Pearlymussel...SUMMARY: We, the U.S. Fish and Wildlife Service...

2013-04-29

13

A Performance Guide to the Music for Flute and Piano by Philippe Gaubert  

Microsoft Academic Search

The purpose of this document is to identify and describe each of the works for flute and piano by Philippe Gaubert. It serves as a resource to flutists to explain the unique and idiomatic way Gaubert wrote for the flute, and will hopefully encourage the study and performance of his music.\\u000aThe famous Méthode Complète de Flûte, begun by Paul

Tammara K. Phillips

2006-01-01

14

Experimental Study of the Compression Response of Fluted-Core Composite Panels with Joints  

NASA Technical Reports Server (NTRS)

Fluted-core sandwich composites consist of integral angled web members spaced between laminate face sheets, and may have the potential to provide benefits over traditional sandwich composites for certain aerospace applications. However, fabrication of large autoclave-cured fluted-core cylindrical shells with existing autoclaves will require that the shells be fabricated in segments, and joined longitudinally to form a complete barrel. Two different longitudinal fluted-core joint designs were considered experimentally in this study. In particular, jointed fluted-core-composite panels were tested in longitudinal compression because longitudinal compression is the primary loading condition in dry launch-vehicle barrel sections. One of the joint designs performed well in comparison with unjointed test articles, and the other joint design failed at loads approximately 14% lower than unjointed test articles. The compression-after-impact (CAI) performance of jointed fluted-core composites was also investigated by testing test articles that had been subjected to 6 ft-lb impacts. It was found that such impacts reduced the load-carrying capability by 9% to 40%. This reduction is dependent on the joint concept, component flute size, and facesheet thickness.

Schultz, Marc R.; Rose, Cheryl A.; Guzman, J. Carlos; McCarville, Douglas; Hilburger, Mark W.

2012-01-01

15

The Life and Contributions of Charles Oliver DeLaney with a Survey of his Compositional Style within his Solo Flute Works  

Microsoft Academic Search

Charles Oliver DeLaney (1925-2006) is considered one of the most influential American flute pedagogues of the twentieth-century. His contributions to the flute community continue to be felt today through his generations of students, many of whom hold prestigious performing and teaching positions. Through organizations such as the National Flute Association (NFA) and the Florida Flute Association (FFA), DeLaney helped establish

Kristin Delia Hayes

2011-01-01

16

Generation and saturation of large-scale flows in flute turbulence  

SciTech Connect

The excitation and suppression of large-scale anisotropic modes during the temporal evolution of a magnetic-curvature-driven electrostatic flute instability are numerically investigated. The formation of streamerlike structures is attributed to the linear development of the instability while the subsequent excitation of the zonal modes is the result of the nonlinear coupling between linearly grown flute modes. When the amplitudes of the zonal modes become of the same order as that of the streamer modes, the flute instabilities get suppressed and poloidal (zonal) flows dominate. In the saturated state that follows, the dominant large-scale modes of the potential and the density are self-organized in different ways, depending on the value of the ion temperature.

Sandberg, I.; Isliker, H.; Pavlenko, V. P.; Hizanidis, K.; Vlahos, L. [School of Electrical and Computer Engineering, National Technical University of Athens, GR-157 73 Athens (Greece); Department of Physics, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki (Greece); Department of Physics, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki (Greece); Department of Astronomy and Space Physics, Uppsala University, Box 515, SE-751 20 Uppsala (Sweden); School of Electrical and Computer Engineering, National Technical University of Athens, GR-157 73 Athens (Greece); Department of Physics, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki (Greece)

2005-03-01

17

Idea Bank: The Native American Flute--A Possibility for Your Classroom  

ERIC Educational Resources Information Center

The sound of the Native American flute seems to convey care, sadness, loneliness, longing, heartfelt emotion, a sense of the natural world, wisdom, the human spirit, and a sense of culture. It is a sound that competes for attention, dramatically punctuating messages about First Nation peoples on television and in movies. A relatively small group…

Kacanek, Hal

2011-01-01

18

Design and analysis of a 5-MW vertical-fluted-tube condenser for geothermal applications  

SciTech Connect

The design and analysis of an industtial-sized vertical-fluted-tube condenser. The condenser is used to condense superheated isobutane vapor discharged from a power turbine in a geothermal test facility operated for the US Department of Energy. The 5-MW condenser has 1150 coolant tubes in a four-pass configuration with a total heat transfer area of 725 m/sup 2/ (7800 ft/sup 2/). The unit is being tested at the Geothermal Components Test Facility in the Imperial Valley of East Mesa, California. The condenser design is based on previous experimental research work done at the Oak Ridge National Laboratory on condensing refrigerants on a wide variety of single vertical tubes. Condensing film coefficients obtained on the high-performance vertical fluted tubes in condensing refrigerants are as much as seven times greater than those obtained with vertical smooth tubes that have the same diameter and length. The overall heat transfer performance expected from the fluted tube condenser is four to five times the heat transfer obtained from the identical units employing smooth tubes. Fluted tube condensers also have other direct applications in the Ocean Thermal Energy Conversion (OTEC) program in condensing ammonia, in the petroleum industry in condensing light hydrocarbons, and in the air conditioning and refrigeration industry in condensing fluorocarbon vapors.

Llewellyn, G.H.

1982-03-01

19

Reproducible fixation with a tapered, fluted, modular, titanium stem in revision hip arthroplasty at 8-15 years follow-up.  

PubMed

The use of tapered, fluted, modular, distally fixing stems has increased in femoral revision surgery. The goal of this retrospective study was to assess mid-term to long-term outcomes of this implant. Seventy-one hips in 70 patients with a mean age of 69 years were followed for an average of 10 years. Preoperative HHS averaged 50 and improved to 87 postoperatively. Seventy-nine percent hips had Paprosky type 3A or more bone-loss. All stems osseointegrated distally (100%). Two hips subsided >5mm but achieved secondary stability. Sixty-eight percent hips had evidence of bony reconstitution and 21% demonstrated diaphyseal stress-shielding. One stem fractured near its modular junction and was revised with a mechanical failure rate of 1.4%. Distal fixation and clinical improvement were reproducibly achieved with this stem design. PMID:24994705

Rodriguez, Jose A; Deshmukh, Ajit J; Robinson, Jonathan; Cornell, Charles N; Rasquinha, Vijay J; Ranawat, Amar S; Ranawat, Chitranjan S

2014-09-01

20

Acomparison of the musical scales of the ancient Chinese bronze bell ensemble and the modern bamboo flute  

Microsoft Academic Search

We compare over a two-octave range the tonal, interval, and scale relationships of an ancient Chinese bell ensemble of the\\u000a Zhou Dynasty and a modern bamboo flute. By using subjective pitches, a tonal system with simple harmonic partials (the flute)\\u000a could be compared with a tonal system with complex inharmonic partials (the bell). We argue that the underlying musical scales

Rao Yu-An; Edward C. Carterette; Wu Yu-Kui

1987-01-01

21

Flute-like musical instruments: A toy model investigated through numerical continuation  

NASA Astrophysics Data System (ADS)

Self-sustained musical instruments (bowed string, woodwind and brass instruments) can be modelled by nonlinear lumped dynamical systems. Among these instruments, flutes and flue organ pipes present the particularity to be modelled as a delay dynamical system. In this paper, such a system, a toy model of flute-like instruments, is studied using numerical continuation. Equilibrium and periodic solutions are explored with respect to the blowing pressure, with focus on amplitude and frequency evolutions along the different solution branches, as well as "jumps" between periodic solution branches. The influence of a second model parameter (namely the inharmonicity) on the behaviour of the system is addressed. It is shown that harmonicity plays a key role in the presence of hysteresis or quasiperiodic regime. Throughout the paper, experimental results on a real instrument are presented to illustrate various phenomena, and allow some qualitative comparisons with numerical results.

Terrien, Soizic; Vergez, Christophe; Fabre, Benoît

2013-07-01

22

Contributing factors, prevention, and management of playing-related musculoskeletal disorders among flute players internationally.  

PubMed

Major studies have shown that flutists report playing-related pain in the neck, middle/upper back, shoulders, wrists, and hands. The current survey was designed to establish the injury concerns of flute players and teachers of all backgrounds, as well as their knowledge and awareness of injury prevention and management. Questions addressed a range of issues including education, history of injuries, preventative and management strategies, lifestyle factors, and teaching methods. At the time of the survey, 26.7% of all respondents were suffering from flute playing-related discomfort or pain; 49.7% had experienced flute playing-related discomfort or pain that was severe enough to distract while performing; and 25.8% had taken an extended period of time off playing because of discomfort or pain. Consistent with earlier studies, the most common pain sites were the fingers, hands, arms, neck, middle/upper back, and shoulders. Further research is needed to establish possible links between sex, instrument types, and ergonomic set up. Further investigation is recommended to ascertain whether certain types of physical training, education, and practice approaches may be more suitable than current methods. A longitudinal study researching the relationship between early education, playing position, ergonomic set-up, and prevalence of injury is recommended. PMID:25194113

Lonsdale, Karen; Laakso, E-Liisa; Tomlinson, Vanessa

2014-09-01

23

The songs of Tlaloc: Interference of ten ceramical duct flutes, Offering 89 of the Aztec Templo Mayor  

NASA Astrophysics Data System (ADS)

Among the many preserved sound artefacts deposited in the offerings of the Aztec Templo Mayor are a set of ten tubular duct flutes made from clay, dating Late Postclassic Mesoamerica, 1350-1521 AD. The aerophones are completely painted in blue, and characterized by: (1) a short mouthpiece; (2) a framed aperture; (3) a tube with four fingerholes; and (4) an applicated mask with features of the Aztec rain god Tlaloc, basically three rings and a standardized relief structure of two clouds. While all measurements follow the same pattern, one particular organological distinction was made, as five flutes show an exit hole in the middle ring of the mask and five flutes are stopped. Thus, five instruments sound considerably higher, apart from the minimal pitch deviation of each specimen. Both the tonal capacity of each flute and the acoustics of several flutes played simultaneously were recorded and measured. A series of remarkable interference effects could be produced, which were strongly related to the ritual complex reflected in the offering. Taking in consideration the Aztec concept of music, it could be supposed that they were perceived as a principle of the song, or proper voice of Tlaloc.

Both, M. A. Adje

2002-11-01

24

Use of the lung flute for sputum induction in children with cystic fibrosis: A pilot study.  

PubMed

This study aimed to assess the effectiveness of the Lung Flute in obtaining a sputum sample from children with cystic fibrosis (CF) that were not productive of sputum with coughing alone. Children attending an outpatient CF clinic who were not able to provide a sample with coughing alone were eligible. Each child used the Lung Flute on two occasions at least one month apart. The primary outcome was expectoration of a sputum sample. Secondary outcomes were sputum microbiology, time taken for the procedure, and ease of use of the device as assessed by the patient using a visual analogue scale (VAS), with 0/10 representing very easy and 10/10 representing very hard. Twenty-five children participated (15 males, mean age 12.7 range 6.5-17.9). Overall, a sputum sample was obtained on 26/50 (52%) uses of the device. In children that presented with a moist cough, a sample was obtained on 17/17 (100%) occasions, compared to 9/33 (27%) occasions when a child presented with a dry cough. A positive culture result for at least one known CF pathogen was found in 24/26 samples. Culture results from obtained samples resulted in management changes in 12 cases. Mean time taken to obtain a sample was 9.8?min (SD 2.2). Mean ease of use on the VAS was 1.5 (SD 1.6). Conclusion: The lung flute appears to be a clinically useful and easy device for sputum induction in children with CF. Further research comparing its effectiveness to other sputum induction methods is warranted. Pediatr Pulmonol. © 2014 Wiley Periodicals, Inc. PMID:25488116

Doumit, Michael; Jaffé, Adam

2014-12-01

25

Simultaneous and integrated neutron-based techniques for material analysis of a metallic ancient flute  

NASA Astrophysics Data System (ADS)

A metallic 19th century flute was studied by means of integrated and simultaneous neutron-based techniques: neutron diffraction, neutron radiative capture analysis and neutron radiography. This experiment follows benchmark measurements devoted to assessing the effectiveness of a multitask beamline concept for neutron-based investigation on materials. The aim of this study is to show the potential application of the approach using multiple and integrated neutron-based techniques for musical instruments. Such samples, in the broad scenario of cultural heritage, represent an exciting research field. They may represent an interesting link between different disciplines such as nuclear physics, metallurgy and acoustics.

Festa, G.; Pietropaolo, A.; Grazzi, F.; Sutton, L. F.; Scherillo, A.; Bognetti, L.; Bini, A.; Barzagli, E.; Schooneveld, E.; Andreani, C.

2013-09-01

26

Lung flute improves symptoms and health status in COPD with chronic bronchitis: A 26 week randomized controlled trial  

PubMed Central

Background Chronic obstructive pulmonary disease (COPD) is characterized by mucus hypersecretion that contributes to disease related morbidity and is associated with increased mortality. The Lung Flute® is a new respiratory device that produces a low frequency acoustic wave with moderately vigorous exhalation to increase mucus clearance. We hypothesized that the Lung Flute, used on a twice daily basis will provide clinical benefit to patients with COPD with chronic bronchitis. Methods We performed a 26 week randomized, non-intervention controlled, single center, open label trial in 69 patients with COPD and Chronic Bronchitis. The primary endpoint was change in respiratory symptoms measured with the Chronic COPD Questionnaire (CCQ). Secondary endpoints included health status, assessed by the St. George Respiratory questionnaire (SGRQ), BODE (Body-Mass Index, Airflow Obstruction, Dyspnea, and Exercise Capacity) index score and exacerbation frequency. Results While the control patients did not demonstrate any significant changes in the primary endpoint (CCQ change at 26 weeks of +0.01, p?=?0.8), a trend (p?=?0.08) to decrease (improvement) in the CCQ (-0.23 at 26 weeks) was seen with the Lung Flute. Furthermore, a significant improvement in the symptom domain of the CCQ was seen only with the lung flute (-0.42, p?=?0.004). Health status (SGRQ) improvement, was also only seen with the Lung Flute (-3.23, p?=?0.03). The BODE score increased in the control group (3.31 at baseline, 4.14 at 26 weeks), however it remained stable in the Lung Flute arm (3.16 at baseline and 26 weeks), with the changes from baseline being significantly different between the 2 arms (p?=?0.01). There was a trend for less exacerbations in the Lung Flute group (p?=?0.07). Adverse effects were minor, with only 1 patient discontinuing treatment because of lack of efficacy. Serious adverse effects seen were all determined to be unrelated to the device use. Conclusions The Lung Flute is a safe and effective treatment in COPD with chronic bronchitis, providing a wide array of benefits. ClinicalTrials.gov Identifier NCT01186822 PMID:25625006

2014-01-01

27

Bone tumor  

MedlinePLUS

Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor ... include: Genetic defects passed down through families Radiation Injury In ... or metastatic bone tumors. They behave very differently ...

28

Effect of germination on bread-making properties of wheat-fluted pumpkin ( Telfairia occidentalis ) seed flour blends  

Microsoft Academic Search

Rheological and bread-making properties of blends containing 0-25% defatted flours from ungerminated and germinated fluted pumpkin (Telfairia occidentalis Hook) seed substituted wheat flour blends were investigated. Dough rheology was studied using a Chopin alveograph, while bread loaves were prepared from the blends using the straight-dough procedure and evaluated for loaf weight, loaf volume, loaf height and sensory characteristics. Up to

Sunday Y. Giami

2003-01-01

29

Multiple antibiotic-resistant bacteria on fluted pumpkin leaves, a herb of therapeutic value.  

PubMed

Fluted pumpkin (Telfairia occidentalis) is a minimally-processed green leafy vegetable traditionally used for its antianaemic properties in the form of leaf juice without a heating or inactivation step before consumption. The aim of the study was to assess the presence of surface microbiota on T. occidentalis leaves and also to determine the antimicrobial susceptibility of isolated organisms. Bacterial contaminants on 50 samples of T. occidentalis leaves were isolated and characterized using standard biochemical methods and the antimicrobial susceptibility of isolated organisms was determined using the antibiotic disc diffusion assay. The results obtained show that the leaves of T. occidentalis is contaminated with organisms which included Enterobacter agglomerans (25.9%), Proteus vulgaris (24.9%), Klebsiella spp. (2.6%), and Serratia liquefaciens (2.1%). Other bacterial isolates recovered in order of frequency included: Staphylococcus spp. (33.7%), Bacillus spp. (8.3%), and Pseudomonas fluorescens (2.6%). Of the 193 bacterial isolates from the leaves of T. occidentalis samples tested for antimicrobial resistance, all (100%) were found to be resistant to ampicillin, cloxacillin, augmentin, erythromycin, and tetracycline while 96% of the isolates were resistant to cephalothin. Resistance to trimethoprim (93%) and gentamicin (83%) was also observed. Approximately, 22% of the isolates were resistant to ciprofloxacin; however, only 11 (5.8%) were resistant to ofloxacin. Thus, uncooked T. occidentalis is a potential source of highly-resistant epiphytic bacteria which could be opportunistic pathogens in consumers. PMID:25076655

Igbeneghu, Oluwatoyin A; Abdu, Abdulrasheed B

2014-06-01

30

Multiple Antibiotic-resistant Bacteria on Fluted Pumpkin Leaves, a Herb of Therapeutic Value  

PubMed Central

ABSTRACT Fluted pumpkin (Telfairia occidentalis) is a minimally-processed green leafy vegetable traditionally used for its antianaemic properties in the form of leaf juice without a heating or inactivation step before consumption. The aim of the study was to assess the presence of surface microbiota on T. occidentalis leaves and also to determine the antimicrobial susceptibility of isolated organisms. Bacterial contaminants on 50 samples of T. occidentalis leaves were isolated and characterized using standard biochemical methods and the antimicrobial susceptibility of isolated organisms was determined using the antibiotic disc diffusion assay. The results obtained show that the leaves of T. occidentalis is contaminated with organisms which included Enterobacter agglomerans (25.9%), Proteus vulgaris (24.9%), Klebsiella spp. (2.6%), and Serratia liquefaciens (2.1%). Other bacterial isolates recovered in order of frequency included: Staphylococcus spp. (33.7%), Bacillus spp. (8.3%), and Pseudomonas fluorescens (2.6%). Of the 193 bacterial isolates from the leaves of T. occidentalis samples tested for antimicrobial resistance, all (100%) were found to be resistant to ampicillin, cloxacillin, augmentin, erythromycin, and tetracycline while 96% of the isolates were resistant to cephalothin. Resistance to trimethoprim (93%) and gentamicin (83%) was also observed. Approximately, 22% of the isolates were resistant to ciprofloxacin; however, only 11 (5.8%) were resistant to ofloxacin. Thus, uncooked T. occidentalis is a potential source of highly-resistant epiphytic bacteria which could be opportunistic pathogens in consumers. PMID:25076655

Abdu, Abdulrasheed B.

2014-01-01

31

Recruitment constraints in Singapore's fluted giant clam (Tridacna squamosa) population—A dispersal model approach  

PubMed Central

Recruitment constraints on Singapore's dwindling fluted giant clam, Tridacna squamosa, population were studied by modelling fertilisation, larval transport, and settlement using real-time hydrodynamic forcing combined with knowledge of spawning characteristics, larval development, behaviour, and settlement cues. Larval transport was simulated using a finite-volume advection-diffusion model coupled to a three-dimensional hydrodynamic model. Three recruitment constraint hypotheses were tested: 1) there is limited connectivity between Singapore's reefs and other reefs in the region, 2) there is limited exchange within Singapore's Southern Islands, and 3) there exist low-density constraints to fertilisation efficacy (component Allee effects). Results showed that connectivity among giant clam populations was primarily determined by residual hydrodynamic flows and spawning time, with greatest chances of successful settlement occurring when spawning and subsequent larval dispersal coincided with the period of lowest residual flow. Simulations suggested poor larval transport from reefs located along the Peninsular Malaysia to Singapore, probably due to strong surface currents between the Andaman Sea and South China Sea combined with a major land barrier disrupting larval movement among reefs. The model, however, predicted offshore coral reefs to the southeast of Singapore (Bintan and Batam) may represent a significant source of larvae. Larval exchange within Singapore's Southern Islands varied substantially depending on the locations of source and sink reefs as well as spawning time; but all simulations resulted in low settler densities (2.1–68.6 settled individuals per 10,000 m2). Poor fertilisation rates predicted by the model indicate that the low density and scattered distribution of the remaining T. squamosa in Singapore are likely to significantly inhibit any natural recovery of local stocks. PMID:23555597

Neo, Mei Lin; Erftemeijer, Paul L. A.; van Beek, Jan K. L.; van Maren, Dirk S.; Teo, Serena L-M.; Todd, Peter A.

2013-01-01

32

Monitoring Gaseous CO2 and Ethanol above Champagne Glasses: Flute versus Coupe, and the Role of Temperature  

PubMed Central

In champagne tasting, gaseous CO2 and volatile organic compounds progressively invade the headspace above glasses, thus progressively modifying the chemical space perceived by the consumer. Simultaneous quantification of gaseous CO2 and ethanol was monitored through micro-gas chromatography (?GC), all along the first 15 minutes following pouring, depending on whether a volume of 100 mL of champagne was served into a flute or into a coupe. The concentration of gaseous CO2 was found to be significantly higher above the flute than above the coupe. Moreover, a recently developed gaseous CO2 visualization technique based on infrared imaging was performed, thus confirming this tendency. The influence of champagne temperature was also tested. As could have been expected, lowering the temperature of champagne was found to decrease ethanol vapor concentrations in the headspace of a glass. Nevertheless, and quite surprisingly, this temperature decrease had no impact on the level of gaseous CO2 found above the glass. Those results were discussed on the basis of a multiparameter model which describes fluxes of gaseous CO2 escaping the liquid phase into the form of bubbles. PMID:22347390

Liger-Belair, Gérard; Bourget, Marielle; Pron, Hervé; Polidori, Guillaume; Cilindre, Clara

2012-01-01

33

Bone Cancer  

MedlinePLUS

Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

34

Field tests of a vertical-fluted-tube condenser in the prototype power plant at the Raft River Geothermal Test Site  

SciTech Connect

A vertical-fluted-tube condenser was designed, fabricated, and tested with isobutane as the shell-side working fluid in a binary prototype power plant at the Raft River Geothermal Test Site. After shakedown and contamination removal operations were completed, the four-pass water-cooled unit (with 102 outside-fluted Admiralty tubes) achieved performance predictions while operating with the plant surface evaporator on-line. A sample comparison shows that use of this enhanced condenser concept offers the potential for a reduction of about 65% from the size suggested by corresponding designs using conventional horizontal-smooth-tube concepts. Subsequent substitution of a direct-contact evaporator for the surface evaporator brought drastic reductions in system performance, the apparent consequence of high concentrations of noncondensible gases introduced by the brine/working-fluid interaction.

Murphy, R.W.

1983-04-01

35

Bone and bone turnover.  

PubMed

Children with cancer are exposed to multiple influences that may adversely affect bone health. Some treatments have direct deleterious effects on bone whilst others may have indirect effects mediated through various endocrine abnormalities. Most clinical outcome studies have concentrated on survivors of acute lymphoblastic leukaemia (ALL). There is now good evidence that earlier treatment protocols that included cranial irradiation with doses of 24 Gy or greater may result in growth hormone deficiency and low bone mineral density (BMD) in the lumbar spine and femoral neck. Under current protocols, BMD decreases during intensive chemotherapy and fracture risk increases. Although total body BMD may eventually return to normal after completion of chemotherapy, lumbar spine trabecular BMD may remain low for many years. The implications for long-term fracture risk are unknown. Risk factors for low BMD include high dose methotrexate, higher cumulative doses of glucocorticoids, male gender and low physical activity. BMD outcome in non-ALL childhood cancers has been less well studied but there is evidence that survivors of childhood brain or bone tumours, and survivors of bone marrow transplants for childhood malignancy, all have a high risk of long-term osteopenia. Long-term follow-up is required, with appropriate treatment of any endocrine abnormalities identified. PMID:19293605

Crofton, Patricia M

2009-01-01

36

The fate of beta-carotene in processed leaves of fluted pumpkin ( Telfairia occidentalis Hook. f.): A popular vegetable in Nigerian diet  

Microsoft Academic Search

The effects of blanching, sun-oven-drying and storage conditions on beta-carotene content of the fresh leaves of fluted pumpkin were investigated. The beta-carotene (mg\\/100 g) of fresh leaves (unblanched) was 98.9 whereas on blanching the value was reduced to 86.3 for steam blanch and 83.8 for water blanch. After dehydration the losses in the beta-carotene were in the ranges of 37.6

G. I. O. Badifu; M. A. Akpapunam; V. M. Mgbemere

1995-01-01

37

A Tradition of Innovation: An Exploration into the History,Cultural Role and Playing of the Atenteben and Odurugya flutes of Ghana  

Microsoft Academic Search

This paper investigates the playing, history and cultural role of the Atenteben family of fipple flutes, and to a larger extent the Odurugya, its brother instrument, and their unique roles as neo-traditional instruments.In order to study the Atenteben,the researcher worked closely with a number of professors at the University of Ghana, Legon, including Ms. Missonu Amu (whose father developed the

Shaun C. Laughlin

2000-01-01

38

Whale bones  

NSDL National Science Digital Library

Vertebrates, or animals that have a skeletal structure for body support, leave bones behind after their death. These bones can be placed together to recreate the skeletal frame of that animal. Bones can be examined to determine what animal the bones came from.

N/A N/A (Go Card USA;)

2007-12-21

39

Bone cement  

PubMed Central

The knowledge about the bone cement is of paramount importance to all Orthopaedic surgeons. Although the bone cement had been the gold standard in the field of joint replacement surgery, its use has somewhat decreased because of the advent of press-fit implants which encourages bone in growth. The shortcomings, side effects and toxicity of the bone cement are being addressed recently. More research is needed and continues in the field of nanoparticle additives, enhanced bone–cement interface etc.

Vaishya, Raju; Chauhan, Mayank; Vaish, Abhishek

2013-01-01

40

Low Bone Density (Osteopenia)  

MedlinePLUS

... are here Home » Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

41

Bone Crusher  

NSDL National Science Digital Library

Students use a tension-compression machine (or an alternative bone-breaking setup) to see how different bones fracture differently and with different amounts of force, depending on their body locations. Teams determine bone mass and volume, calculate bone density, and predict fracture force. Then they each test a small animal bone (chicken, turkey, cat) to failure, examining the break to analyze the fracture type. Groups conduct research about biomedical challenges, materials and repair methods, and design repair treatment plans specific to their bones and fracture types, presenting their design recommendations to the class.

2014-09-18

42

Bone Basics  

NSDL National Science Digital Library

This is an activity (on page 2 of the PDF) about the two main components of bone - collagen and minerals (like calcium) - and how they each contribute to its flexibility and strength. Learners will submerge 3 chicken bones in water, bleach, and vinegar, wait 24 hours, then observe and test each bone. This resource includes information about how nanoscientists are trying to produce artificial analogs to these components and relates to linked video, DragonflyTV Nano: Bone Regrowth.

Twin Cities Public Television, Inc.

2008-01-01

43

Bone scan  

MedlinePLUS

A bone scan is an imaging test that shows areas of increased or decreased bone turnover ( metabolism ). ... have taken up less of the radioactive material. Bone scan findings must be compared with other imaging studies, in addition to clinical information. Your health ...

44

Uncemented femoral revision arthroplasty using a modular tapered, fluted titanium stem  

PubMed Central

Background and purpose — Due to the relative lack of reports on the medium- to long-term clinical and radiographic results of modular femoral cementless revision, we conducted this study to evaluate the medium- to long-term results of uncemented femoral stem revisions using the modular MRP-TITAN stem with distal diaphyseal fixation in a consecutive patient series. Patients and methods — We retrospectively analyzed 163 femoral stem revisions performed between 1993 and 2001 with a mean follow-up of 10 (5–16) years. Clinical assessment included the Harris hip score (HHS) with reference to comorbidities and femoral defect sizes classified by Charnley and Paprosky. Intraoperative and postoperative complications were analyzed and the failure rate of the MRP stem for any reason was examined. Results — Mean HHS improved up to the last follow-up (37 (SD 24) vs. 79 (SD 19); p < 0.001). 99 cases (61%) had extensive bone defects (Paprosky IIB–III). Radiographic evaluation showed stable stem anchorage in 151 cases (93%) at the last follow-up. 10 implants (6%) failed for various reasons. Neither a breakage of a stem nor loosening of the morse taper junction was recorded. Kaplan-Meier survival analysis revealed a 10-year survival probability of 97% (95% CI: 95–100). Interpretation — This is one of the largest medium- to long-term analyses of cementless modular revision stems with distal diaphyseal anchorage. The modular MRP-TITAN was reliable, with a Kaplan-Meier survival probability of 97% at 10 years. PMID:25175667

Wirtz, Dieter C; Gravius, Sascha; Ascherl, Rudolf; Forst, Raimund; Noeth, Ulrich; Maus, Uwe M; Zeiler, Günther; Moritz C, Deml

2014-01-01

45

INVEST IN YOUR BONES Bone Basics  

E-print Network

to left) to become so fragile (see above bone figure to right) that they break. Bone Basics You may think. Keeping your bones healthy by preventing osteoporosis is particularly important as you age. Bones are changing constantly with fragments of old bone being removed and replaced by new bone. Think of bones like

46

Influence of Non-MHD Flutes on the Efficiency of Energy Transfer from the Laser-Produced, ICF and Space Exploding Plasmas to Magnetic Field  

SciTech Connect

The results of <> experiment with quasispherical Laser-produced Plasma Clouds (LPC) expanding into strong (B{sub 0} {approx}10 kG) and uniform magnetic field at KI-1 facility of ILP are presented. Main characteristics and the influence of non-MHD flute instability onto effectiveness of plasma-field interaction were studied especially for the purpose of plasma confinement and the direct conversion of its kinetic energy into magnetic and electric ones (of pick-up coils). A new model of enhanced field penetration into plasma due to Hall-effect in its flutes and under conditions of finite ion Larmor radius is discussed. The data obtained on the current generation by LPC in short-circuited surrounding coils (with total conversion efficiency up to {approx}10%) are compared with the models of ILP and last results of relevant 3D/PIC calculations done at KU. All these results show the opportunities of LPC-experiments to simulate both space exploding plasmas (AMPTE) and MHD-effects of ICF micro-explosions in planned NIF experiments for study Laser Fusion Rocket like a VISTA.

Zakharov, Yuri P.; Antonov, Vladimir M.; Boyarintsev, Eduard L.; Melekhov, Alexandr V.; Posukh, Vitaliy G.; Shaikhislamov, Ildar F.; Nakashima, Hideki; Vchivkov, Konstantin V

2005-01-15

47

Bear Bones  

NSDL National Science Digital Library

An estimated ten million Americans have osteoporosis, an age-related disease in which the bones gradually become brittle and weak. Now, scientists are looking to animals for clues on how to combat this condition. This resource describes the study of sustaining bone strength of hibernating bears.

Science Update;

2004-03-08

48

Bone Sialoprotein  

Microsoft Academic Search

The search for a protein nucleator of hydroxyapatite crystal formation has been a focus for the isolation and characterization of the major non-collagenous proteins in bone. Of the proteins characterized to date, bone sialoprotein (BSP) has emerged as the only bona fide candidate for nucleation. BSP is a highly glycosylated and sulphated phosphoprotein that is found almost exclusively in mineralized

B. Ganss; R. H. Kim; J. Sodek

1999-01-01

49

The Comparison of the Effect of Block Flute Accompanied Song Teaching with Multi-Sound Notation and Vocalization Program Accompanied Song Teaching on the Success of Students' Song Learning Behavior  

ERIC Educational Resources Information Center

This experimental study was done to see if using computer supported notation and vocalization program for teaching songs instead of using block flute accompanied song teaching has any significant effect on students' singing behavior. The study group is composed of the 5th, 6th and 7th graders of 2008-2009 educational term in T.O.K.I. Yahya Kemal…

Saktanli, S. Cem

2011-01-01

50

Bone Densitometry  

MedlinePLUS Videos and Cool Tools

... In people with osteoporosis, new bone has less calcium in it and is therefore weaker than the ... 1 Some antacids contain aluminum hydroxide, which prevents calcium from being absorbed by the body. People who ...

51

Interpreting Bones.  

ERIC Educational Resources Information Center

Describes an activity which introduces students to the nature and challenges of paleoanthropology. In the exercise, students identify diagrammed bones and make interpretations about the creature. Presents questions and tasks employed in the lesson. (ML)

Weymouth, Patricia P.

1986-01-01

52

Bone marrow transplant  

MedlinePLUS

Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity, nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; Umbilical ...

53

Bone Graft Alternatives  

MedlinePLUS

... or during a surgical procedure such as spinal fusion. What Types of Bone Grafts are There? Bone ... bone grafts in spine surgery is during spinal fusion. The use of autogenous bone grafts for spinal ...

54

[Bone transplant].  

PubMed

We describe the methodology of the Bone and Soft Tissue Bank, from extraction and storage until use. Since the year 1986, with the creation of the Bone Bank in the University Clinic of Navarra, more than 3,000 grafts have been used for very different types of surgery. Bone grafts can be classified into cortical and spongy; the former are principally used in surgery to save tumour patients, in large post-traumatic reconstructions and in replacement surgery where there are massive bone defects and a structural support is required. The spongy grafts are the most used due to their numerous indications; they are especially useful in filling cavities that require a significant quantity of graft when the autograft is insufficient, or as a complement. They are also of special help in treating fractures when there is bone loss and in the treatment of delays in consolidation and pseudoarthrosis in little vascularized and atrophic zones. They are also used in prosthetic surgery against the presence of cavity type defects. Allografts of soft tissues are specially recognised in multiple ligament injuries that require reconstructions. Nowadays, the most utilised are those employed in surgery of the anterior cruciate ligament although they can be used for filling any ligament or tendon defect. The principal difficulties of the cortical allografts are in the consolidation of the ends with the bone itself and in tumour surgery, given that these are patients immunodepressed by the treatment, the incidence of infection is increased with respect to spongy grafts and soft tissues, which is irrelevant. In short, the increasingly widespread use of allografts is an essential therapeutic weapon in orthopaedic surgery and traumatology. It must be used by expert hands. PMID:16998521

San Julián, M; Valentí, A

2006-01-01

55

Bone substitutes: new concepts  

Microsoft Academic Search

The filling of bone defects resulting from trauma or surgical resections of tumors requires bone grafts or bone substitutes. Bone substitute must be biocompatible, osteoconductive, and must present good mechanical properties. Among biomaterials classicaly used, calcium phosphate ceramic appear to be suitable alternatives to bone grafts. Calcium phosphate are known able to promote new bone formation on contact and have

D. Heymann; N. Passuti

1999-01-01

56

Dem Bones  

NSDL National Science Digital Library

In this case, students enter the world of a forensic anthropologist who must determine the sex and age of an individual from a collection of bones. Students, in turn, simulate some of the actual procedures conducted in a forensic anthropologist's lab, exa

Alease Bruce

2001-09-01

57

Broken bone  

MedlinePLUS

... or strips of wood. Immobilize the area both above and below the injured bone. Apply ice packs to reduce pain and swelling. Take steps to prevent shock . Lay the person flat, elevate the feet about 12 inches above the head, and cover the person with a ...

58

From Bone Biology to Bone Analysis  

Microsoft Academic Search

Bone development is one of the key processes characterizing childhood and adolescence. Understanding this process is not only important for physicians treating pediatric bone disorders, but also for clinicians and researchers dealing with postmenopausal and senile osteoporosis. Bone densitometry has great potential to enhance our understanding of bone development. The usefulness of densitometry in children and adolescents would be increased

E. Schoenau; G. Saggese; F. Peter; G. I. Baroncelli; N. J. Shaw; N. J. Crabtree; Z. Zadik; C. M. Neu; C. Noordam; G. Radetti; Z. Hochberg

2004-01-01

59

Bone substitutes and bone formation  

Microsoft Academic Search

Summary  \\u000a Prompted by severe problems in autogeneic and allogeneic bone transplantation, intensive efforts were made to find sufficient\\u000a substitutes. A main demand on these materials, especially in healing of osseous defects, is to achieve results comparable\\u000a to those of auto- or allografts. These must be related to their biomechanical and particularly to their biological properties,\\u000a i. e. the ability to

H. Stützle; K. Hallfeldt; H. Mandelkow; S. Keßler; L. Schweiberer

1998-01-01

60

What causes bone loss?  

MedlinePLUS

... or keeps your body from making enough bone. Weak bones can break easily, even without an obvious ... to be poorly absorbed can also lead to weak bones. Some of these are: Gastric bypass (weight- ...

61

Disorders of Bone Remodeling  

PubMed Central

The skeleton provides mechanical support for stature and locomotion, protects vital organs, and controls mineral homeostasis. A healthy skeleton must be maintained by constant bone modeling to carry out these crucial functions throughout life. Bone remodeling involves the removal of old or damaged bone by osteoclasts (bone resorption) and the subsequent replacement of new bone formed by osteoblasts (bone formation). Normal bone remodeling requires a tight coupling of bone resorption to bone formation to guarantee no alteration in bone mass or quality after each remodeling cycle. However, this important physiological process can be derailed by a variety of factors, including menopause-associated hormonal changes, age-related factors, changes in physical activity, drugs, and secondary diseases, which lead to the development of various bone disorders in both women and men. We review the major diseases of bone remodeling, emphasizing our current understanding of the underlying pathophysiological mechanisms. PMID:20936937

Feng, Xu; McDonald, Jay M.

2013-01-01

62

Dinosaur Bone Experiments  

NSDL National Science Digital Library

This activity features two connected hands-on activities about dinosaur bones. Using chicken or turkey bones and regular household items, learners explore the scientific process of studying fossilized bones. By exposing the bones to vinegar or heat, learners begin to understand how paleontologists use chemical processes to study the bones of animals long dead and gone. Use this bone-themed activity around the Thanksgiving holiday and repurpose some leftovers.

Lawrence Hall of Science

2005-01-01

63

Bone scan appearances following biopsy of bone and bone marrow  

SciTech Connect

The influence of sternal marrow aspiration, iliac crest marrow aspiration, and iliac crest bone biopsy on bone scan appearances was examined. Eighteen patients were scanned a mean of 9.9 days after sternal marrow aspiration with a Salah needle. Bone scans obtained in 9 patients a mean of 10 days aftr iliac crest trephine marrow biopsy with a Jamshidi needle showed no abnormality at the biopsy site. In 18 patients with metabolic bone disease who had undergone iliac crest bone biopsy with an 8 mm needle, a scan abnormality due to the biopsy was usually present when the interval between the biopsy and the scan was 5 days to 2 months. Patients who were scanned within 3 days of iliac crest bone biopsy or more than 2 months after biopsy had normal scan appearance at the biopsy site.

McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

1984-10-01

64

Menopause and Bone Loss  

MedlinePLUS

... become irregular, your estrogen levels may start to drop off and you could start to lose bone more rapidly. Over time, this bone loss can lead to osteopenia (low bone mass) or even osteoporosis, a condition in which bones become weak and are more likely to break (fracture). did ...

65

Bone grafts in dentistry  

PubMed Central

Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation. PMID:23946565

Kumar, Prasanna; Vinitha, Belliappa; Fathima, Ghousia

2013-01-01

66

Metabolic bone disease  

Microsoft Academic Search

Bone is a complex organ that is highly metabolically active, particularly in children. Normal metabolism is dependent upon the three main elements, matrix, mineral and cells that are integral components of bone. In addition, there are several humoral factors that also influence bone. Abnormalities in any of these components can give rise to metabolic bone disease. Abnormalities of mineralisation are

Jeremy Allgrove

2011-01-01

67

[Bone and androgens].  

PubMed

Sexual steroids are major determinants of skeletal maturation and steady state. Estrogens are mandatory in both sexes. They induce endochondral bone formation and growth plate knitting. Androgens are mainly active in male. They increase length and radial bone growth. These differences explain the duality of biomechanics in both sexes. Deep androgen deficiency induces rapid bone loss and increases bone fracture risk. The androgen treatment of andropause has weak rationale. Androgens interact with bone metabolism within the medulla-bone unit. They activate the whole osteoblastic lineage and interact with preosteoclastic regulation. Androgens found their place in bone metabolism regulation through RANK/osteoprotegerin and Wnt/sclerostin pathways. PMID:24332181

Weryha, Georges; Angelousi, Anna; Diehdiou, Demba; Cuny, Thomas

2014-02-01

68

Basic bone radiology  

SciTech Connect

This clinical book surveys the skeletal system as seen through radiological imaging. It emphasizing abnormalities, disease, and trauma, and includes vital information on bones, bone growth, and the cells involved in bone pathology. It covers many bone diseases and injuries which are rarely covered in medical texts, as well as descriptions of radiologic procedures that specifically relate to the skeleton. This edition includes many illustrations, information on MR imaging and CT scanning, and discussions of osteoporosis, dysplasias, and metabolic bone disease.

Griffiths, H.J.

1987-01-01

69

Oxytocin and bone.  

PubMed

One of the most meaningful results recently achieved in bone research has been to reveal that the pituitary hormones have profound effect on bone, so that the pituitary-bone axis has become one of the major topics in skeletal physiology. Here, we discuss the relevant evidence about the posterior pituitary hormone oxytocin (OT), previously thought to exclusively regulate parturition and breastfeeding, which has recently been established to directly regulate bone mass. Both osteoblasts and osteoclasts express OT receptors (OTR), whose stimulation enhances bone mass. Consistent with this, mice deficient in OT or OTR display profoundly impaired bone formation. In contrast, bone resorption remains unaffected in OT deficiency because, even while OT stimulates the genesis of osteoclasts, it inhibits their resorptive function. Furthermore, in addition to its origin from the pituitary, OT is also produced by bone marrow osteoblasts acting as paracrine-autocrine regulator of bone formation modulated by estrogens. In turn, the power of estrogen to increase bone mass is OTR-dependent. Therefore, OTR(-/-) mice injected with 17?-estradiol do not show any effects on bone formation parameters, while the same treatment increases bone mass in wild-type mice. These findings together provide evidence for an anabolic action of OT in regulating bone mass and suggest that bone marrow OT may enhance the bone-forming action of estrogen through an autocrine circuit. This established new physiological role for OT in the maintenance of skeletal integrity further suggests the potential use of this hormone for the treatment of osteoporosis. PMID:25209411

Colaianni, Graziana; Sun, Li; Zaidi, Mone; Zallone, Alberta

2014-10-15

70

Anorexia Nervosa and Bone  

PubMed Central

Anorexia nervosa (AN) is a condition of severe low weight that is associated with low bone mass, impaired bone structure and reduced bone strength, all of which contribute to increased fracture risk., Adolescents with AN have decreased rates of bone accrual compared with normal-weight controls, raising addition concerns of suboptimal peak bone mass and future bone health in this age group. Changes in lean mass and compartmental fat depots, hormonal alterations secondary to nutritional factors contribute to impaired bone metabolism in AN. The best strategy to improve bone density is to regain weight and menstrual function. Oral estrogen-progesterone combinations are not effective in increasing bone density in adults or adolescents with AN, and transdermal testosterone replacement is not effective in increasing bone density in adult women with AN. However, physiologic estrogen replacement as transdermal estradiol with cyclic progesterone does increase bone accrual rates in adolescents with AN to approximate that in normal-weight controls, leading to a maintenance of bone density Z-scores. A recent study has shown that risedronate increases bone density at the spine and hip in adult women with AN. However, bisphosphonates should be used with great caution in women of reproductive age given their long half-life and potential for teratogenicity, and should be considered only in patients with low bone density and clinically significant fractures when non-pharmacological therapies for weight gain are ineffective. Further studies are necessary to determine the best therapeutic strategies for low bone density in AN. PMID:24898127

Misra, Madhusmita; Klibanski, Anne

2014-01-01

71

Carpal bone analysis in bone age assessment  

NASA Astrophysics Data System (ADS)

A computer-aided-diagnosis (CAD) method has been previously developed in our Laboratory based on features extracted from regions of interest (ROI) in phalanges in a digital hand atlas. Due to various factors, including, the diversity of size, shape and orientation of carpal bones, non-uniformity of soft tissue, low contrast between the bony structure and soft tissue, the automatic identification and segmentation of bone boundaries is an extremely challenging task. Past research work on carpal bone segmentation has been done utilizing dynamic thresholding. However, due to the discrepancy of carpal bones developments and the limitations of segmentation algorithms, carpal bone ROI has not been taken into consideration in the bone age assessment procedure. In this paper, we present a method for fully automatic carpal bone segmentation and feature analysis in hand X-ray radiograph. The purpose of this paper is to automatically segment the carpal bones by anisotropic diffusion and Canny edge detection techniques. By adding their respective features extracted from carpal bones ROI to the phalangeal ROI feature space, the accuracy of bone age assessment can be improved especially when the image processing in the phalangeal ROI fails in younger children.

Zhang, Aifeng; Gertych, Arkadiusz; Kurkowska-Pospiech, Sylwia; Liu, Brent J.; Huang, H. K.

2006-03-01

72

Bone Builders: The Science of Grafts, Biomaterials and Bone Engineering  

NSDL National Science Digital Library

FASEB Breakthroughs in Bioscience article. Every year, more than 800,000 people in the United States receive bone biomaterials, including bone grafts and bone graft substitutes. Bone is the most commonly transplanted tissue after blood transfusions. Unlike most tissues, bone is able to regenerate and reform without scarring, given the proper conditions and materials. Researchers and scientists have learned to exploit this property over many centuries to create modern day bone grafts and bone biomaterials used as substitutes for bone grafts.

Steven Stocker (x)

2009-07-22

73

Smoking and Bone Health  

MedlinePLUS

... supported by your browser. Home Bone Basics Lifestyle Smoking and Bone Health Publication available in: PDF (217 ... Overtraining Risks for Women Oral Health Partner Resources Smoking: It’s Never Too Late to Stop (NIA)

74

Bone Marrow Tests  

MedlinePLUS

... diagnose fevers and infections. The two bone marrow tests are aspiration (as-pi-RA-shun) and biopsy. Bone marrow aspiration usually is done first. For this test, your doctor removes a small amount of fluid ...

75

Related disorders of bone  

Microsoft Academic Search

Renal osteodystrophy includes a broad spectrum of abnormalities in bone and mineral metabolism. This review article discusses\\u000a related bone disorders, including calcific uremic arteriolopathy, “osteoporosis” and compromised bone strength, and dialysis-related\\u000a amyloidosis, as well as the contributing roles of glucocorticoids and metabolic acidosis. Bone disorders in the setting of\\u000a renal transplantation, including osteoporosis, osteonecrosis, and presistent hyperparathyroidism, are also reviewed.

Francis L. Weng; Stanley Goldfarb

2007-01-01

76

Metabolic Bone Disease  

Microsoft Academic Search

\\u000a Metabolic bone disease encompasses a number of disorders that typically show involvement of the entire skeleton. They are\\u000a mostly associated with increased bone turnover and increased uptake of radiolabeled diphosphonate. The increased uptake produces\\u000a heightened contrast on bone scan between bone and soft tissues, deceptively giving the appearance of excellent image quality.\\u000a In more severe cases, there may be characteristic

Paul J. Ryan

77

Bone loss and teeth  

Microsoft Academic Search

Loss of teeth results in irreversible alveolar bone resorption, and untreated dental disease causes alveolar bone lysis that ultimately leads to loss of teeth. In addition to anchoring the teeth in the alveolar ridge, the maxillary and mandibular bone allows dental restoration procedures, such as construction of root-supported implants, fixed dentures, or removable dentures. However, the functional and cosmetic results

François Bodic; Luc Hamel; Emmanuelle Lerouxel; Michel Félix Baslé; Daniel Chappard

2005-01-01

78

Demineralized Bone Matrix: Maximizing New Bone Formation for Successful Bone Implantation  

Microsoft Academic Search

\\u000a The bone scaffold formed by ground cortical bone and cancel-lous chips creates the favorable environment required for bone-forming\\u000a cells to be able to generate new bone; this property is called osteoconductivity. The demineralization of bone matrix exposes bone morphogenetic proteins (BMPs) and other bone growth promoting factors.\\u000a Because of this, deminer-alized bone matrix (DBM) not only provides a scaffold for

Lloyd Wolfinbarger Jr; Liisa M. Eisenlohr; Katrina Ruth

79

Method for fusing bone  

DOEpatents

Method for fusing bone. The present invention is a method for joining hard tissue which includes chemically removing the mineral matrix from a thin layer of the surfaces to be joined, placing the two bones together, and heating the joint using electromagnetic radiation. The goal of the method is not to produce a full-strength weld of, for example, a cortical bone of the tibia, but rather to produce a weld of sufficient strength to hold the bone halves in registration while either external fixative devices are applied to stabilize the bone segments, or normal healing processes restore full strength to the tibia.

Mourant, Judith R. (Los Alamos, NM); Anderson, Gerhard D. (Velarde, NM); Bigio, Irving J. (Los Alamos, NM); Johnson, Tamara M. (Los Alamos, NM)

1996-01-01

80

Calcium and bone disease  

PubMed Central

Calcium transport and calcium signaling are of basic importance in bone cells. Bone is the major store of calcium and a key regulatory organ for calcium homeostasis. Bone, in major part, responds to calcium-dependent signals from the parathyroids and via vitamin D metabolites, although bone retains direct response to extracellular calcium if parathyroid regulation is lost. Improved understanding of calcium transporters and calcium-regulated cellular processes has resulted from analysis of genetic defects, including several defects with low or high bone mass. Osteoblasts deposit calcium by mechanisms including phosphate and calcium transport with alkalinization to absorb acid created by mineral deposition; cartilage calcium mineralization occurs by passive diffusion and phosphate production. Calcium mobilization by osteoclasts is mediated by acid secretion. Both bone forming and bone resorbing cells use calcium signals as regulators of differentiation and activity. This has been studied in more detail in osteoclasts, where both osteoclast differentiation and motility are regulated by calcium. PMID:21674636

Blair, Harry C.; Robinson, Lisa J.; Huang, Christopher L.-H.; Sun, Li; Friedman, Peter A.; Schlesinger, Paul H.; Zaidi, Mone

2013-01-01

81

Bone disease in thyrotoxicosis  

PubMed Central

Thyrotoxicosis, a clinical syndrome characterized by manifestations of excess thyroid hormone, is one of the commonly-recognised conditions of the thyroid gland. Thyrotoxicosis causes acceleration of bone remodelling and though it is one of the known risk factors for osteoporosis, the metabolic effects of thyroxine on bone are not well discussed. Studies show that thyroid hormones have effects on bone, both in vitro and in vivo. Treatment of thyrotoxicosis leads to reversal of bone loss and metabolic alterations, and decreases the fracture risk. There are limited studies in India as to whether these changes are fully reversible. In this review we discuss about the effects of thyrotoxicosis (endogenous and exogenous) on bone and mineral metabolism, effects of subclinical thyrotoxicosis on bone and mineral metabolism and effects of various forms of treatment in improving the bone mineral density in thyrotoxicosis. PMID:22561612

Reddy, P. Amaresh; Harinarayan, C. V.; Sachan, Alok; Suresh, V.; Rajagopal, G.

2012-01-01

82

Major bone defect treatment with an osteoconductive bone substitute  

Microsoft Academic Search

A bone defect can be provoked by several pathological conditions (e.g. bone tumours, infections, major trauma with bone stock\\u000a loss) or by surgical procedures, required for the appropriate treatment. Surgical techniques currently used for treating bone\\u000a defects may count on different alternatives, including autologous vascularized bone grafts, homologous bone graft provided\\u000a by musculoskeletal tissue bank, heterologous bone graft (xenograft), or

Stefania Paderni; S. Terzi; L. Amendola

2009-01-01

83

Remodeling in bone without osteocytes: Billfish challenge bone structurefunction paradigms  

E-print Network

Remodeling in bone without osteocytes: Billfish challenge bone structure­function paradigms Ayelet of bone, is considered to be initiated and orchestrated by osteocytes, cells within the bone matrix. It is therefore surprising that most extant fishes (neoteleosts) lack osteocytes, suggesting their bones

Lajeunesse, Marc J.

84

Assessment of Long Bone Flexural Properties from Bone Densitometry  

NASA Technical Reports Server (NTRS)

While bone densitometry is the accepted non-invasive method of quantifying bone mineral content in bones, its assessment of bone structural properties is less well understood. The objective of our current work is to compare cross-section shape or areal properties of long bones computed from densitometry data with cross-section flexural properties obtained from surface strain measurements.

Whalen, Robert; Cleek, Tammy; Katz, BethAnn

1994-01-01

85

Biomaterials and bone mechanotransduction  

NASA Technical Reports Server (NTRS)

Bone is an extremely complex tissue that provides many essential functions in the body. Bone tissue engineering holds great promise in providing strategies that will result in complete regeneration of bone and restoration of its function. Currently, such strategies include the transplantation of highly porous scaffolds seeded with cells. Prior to transplantation the seeded cells are cultured in vitro in order for the cells to proliferate, differentiate and generate extracellular matrix. Factors that can affect cellular function include the cell-biomaterial interaction, as well as the biochemical and the mechanical environment. To optimize culture conditions, good understanding of these parameters is necessary. The new developments in bone biology, bone cell mechanotransduction, and cell-surface interactions are reviewed here to demonstrate that bone mechanotransduction is strongly influenced by the biomaterial properties.

Sikavitsas, V. I.; Temenoff, J. S.; Mikos, A. G.; McIntire, L. V. (Principal Investigator)

2001-01-01

86

Small Animal Bone Biomechanics  

PubMed Central

Animal models, in particular mice, offer the possibility of naturally achieving or genetically engineering a skeletal phenotype associated with disease and conducting destructive fracture tests on bone to determine the resulting change in bone’s mechanical properties. Several recent developments, including nano- and micro- indentation testing, microtensile and microcompressive testing, and bending tests on notched whole bone specimens, offer the possibility to mechanically probe small animal bone and investigate the effects of aging, therapeutic treatments, disease, and genetic variation. In contrast to traditional strength tests on small animal bones, fracture mechanics tests display smaller variation and therefore offer the possibility of reducing sample sizes. This article provides an analysis of what such tests measure and proposes methods to reduce errors associated with testing smaller than ideal specimens. PMID:18672104

Vashishth, Deepak

2008-01-01

87

Radionuclide bone imaging and densitometry  

SciTech Connect

This book contains 13 selections. Some of the titles are: Radionuclides and the Normal Bone Scan; The Radionuclide Bone Scan in Malignant Disease; Pediatric Applications of Radionuclide Bone Imaging; The Radionuclide Bone Scan in Arthritis and Metabolic and Miscellaneous Disorders; and Soft Tissue Activity on the Radionuclide Bone Scan.

Mettler, F.A.

1988-01-01

88

Review of Bone Substitutes  

PubMed Central

Bone substitutes are being increasingly used in craniofacial surgery and craniomaxillofacial trauma. We will review the history of the biomaterials and describe the ideal characteristics of bone substitutes, with a specific emphasis on craniofacial reconstruction. Some of the most commonly used bone substitutes are discussed in more depth, such as calcium phosphate and hydroxyapatite ceramics and cements, bioactive glass, and polymer products. Areas of active research and future directions include tissue engineering, with an increasing emphasis on bioactivity of the implant. PMID:22110809

Pryor, Landon S.; Gage, Earl; Langevin, Claude-Jean; Herrera, Fernando; Breithaupt, Andrew D.; Gordon, Chad R.; Afifi, Ahmed M.; Zins, James E.; Meltzer, Hal; Gosman, Amanda; Cohen, Steve R.; Holmes, Ralph

2009-01-01

89

Method for fusing bone  

DOEpatents

The present invention is a method for joining hard tissue which includes chemically removing the mineral matrix from a thin layer of the surfaces to be joined, placing the two bones together, and heating the joint using electromagnetic radiation. The goal of the method is not to produce a full-strength weld of, for example, a cortical bone of the tibia, but rather to produce a weld of sufficient strength to hold the bone halves in registration while either external fixative devices are applied to stabilize the bone segments, or normal healing processes restore full strength to the tibia.

Mourant, J.R.; Anderson, G.D.; Bigio, I.J.; Johnson, T.M.

1996-03-12

90

Breast Cancer and Bone Loss  

MedlinePLUS

... Breast Cancer and Bone Loss Share: Fact Sheet Breast Cancer and Bone Loss July, 2010 Download PDFs English ... JoAnn Pinkerton, MD What is the link between breast cancer and bone loss? Certain treatments for breast cancer ...

91

Biodegradable synthetic bone composites  

DOEpatents

The invention provides for a biodegradable synthetic bone composition comprising a biodegradable hydrogel polymer scaffold comprising a plurality of hydrolytically unstable linkages, and an inorganic component; such as a biodegradable poly(hydroxyethylmethacrylate)/hydroxyapatite (pHEMA/HA) hydrogel composite possessing mineral content approximately that of human bone.

Liu, Gao; Zhao, Dacheng; Saiz, Eduardo; Tomsia, Antoni P.

2013-01-01

92

Metabolic bone disease  

Microsoft Academic Search

Metabolic bone dlseases are frequently seen in the geriatric population. The pain which often accompanies the disorder is\\u000a a major cause of morbidity, frequent visits to the physician, health resource utilization, and even mortality. Successful\\u000a prevention, detection and management of metabolic bone disease are essential components of optimal geriatric health care.

Jeffrey E. Escher; Steven Gambert; Bruce Rothschild

1987-01-01

93

Metabolic bone disease  

Microsoft Academic Search

Metabolic bone disease results from a complex variety of causes but can generally be divided into conditions that mainly cause osteoporosis and those that result principally in osteomalacia. Some conditions show a mixture of these two states. Investigation of metabolic bone disease should follow a logical progression and a diagnosis can usually be made if this sequence is adhered to.

Jeremy Allgrove

2007-01-01

94

Metabolic bone disease  

Microsoft Academic Search

Metabolic bone disease is most often diagnosed by a combination of radiological features, clinical signs and symptoms and biochemistry for serum calcium, phosphate and alkaline phosphatase. The most common metabolic bone disease is osteoporosis which affects elderly patients, particularly women and is a disease on the increase in the Western world. It is now recognized that osteoporosis can be of

A. J. Malcolm

2002-01-01

95

Wnt Signaling in Bone  

PubMed Central

Wnt signaling is involved not only in embryonic development but also in maintenance of homeostasis in postnatal tissues. Multiple lines of evidence have increased understanding of the roles of Wnt signaling in bone since mutations in the LRP5 gene were identified in human bone diseases. Canonical Wnt signaling promotes mesenchymal progenitor cells to differentiate into osteoblasts. The canonical Wnt/?-catenin pathway possibly through Lrp6, a co-receptor for Wnts as well as Lrp5, in osteoblasts regulates bone resorption by increasing the OPG/RANKL ratio. However, endogenous inhibitors of Wnt signaling including sclerostin block bone formation. Regulation of sclerostin appears to be one of the mechanisms of PTH anabolic actions on bone. Since sclerostin is almost exclusively expressed in osteocytes, inhibition of sclerostin is the most promising design. Surprisingly, Lrp5 controls bone formation by inhibiting serotonin synthesis in the duodenum, but not by directly promoting bone formation. Pharmacological intervention may be considered in many components of the canonical Wnt signaling pathway, although adverse effects and tumorigenicity to other tissues are important. More studies will be needed to fully understand how the Wnt signaling pathway actually influences bone metabolism and to assure the safety of new interventions. PMID:23926379

Kubota, Takuo; Michigami, Toshimi; Ozono, Keiichi

2010-01-01

96

Repairing Broken Bones  

NSDL National Science Digital Library

Students learn about how biomedical engineers aid doctors in repairing severely broken bones. They learn about using pins, plates, rods and screws to repair fractures. They do this by designing, creating and testing their own prototype devices to repair broken turkey bones.

Integrated Teaching and Learning Program, College of Engineering,

97

Bone Fractures and Engineering  

NSDL National Science Digital Library

Students learn about the role engineers and engineering play in repairing severe bone fractures. They acquire knowledge about the design and development of implant rods, pins, plates, screws and bone grafts. They learn about materials science, biocompatibility and minimally-invasive surgery.

Integrated Teaching and Learning Program, College of Engineering,

98

Depression and Bone Metabolism  

Microsoft Academic Search

Background: There are data to suggest low bone mineral density is disproportionately prevalent among those with psychiatric disorders. This paper aims to review the current evidence on the relationship between depression and bone mineral density, and identify potential mechanisms. Methods: Relevant sources were identified from the Pubmed and Web of Science (ISI) databases from the first relevant publication in 1994

Lana J. Williams; Julie A. Pasco; Felice N. Jacka; Margaret J. Henry; Seetal Dodd; Michael Berk

2009-01-01

99

Primary leiomyosarcoma of bone  

Microsoft Academic Search

Sixteen cases of primary leiomyosarcoma of bone are described. The patients, 11 males and 5 females, ranged in age from 9 to 74 years. The annual incidence of this tumor in Sweden was calculated to be 0.09 cases per million. This figure was obtained by reviewing a Swedish series of spindle cell sarcomas of bone of which one quarter (11\\/44)

Lennart Angervall; Lars-Gunnar Kindblom; Isabelita C. Berlin; Bertil Stener

1987-01-01

100

Bone chemistry and bioarchaeology  

Microsoft Academic Search

Isotopic analysis of bones and teeth is now routinely used for dating skeletons and archaeological sites, and for diet, climate, and habitat reconstruction. Techniques of radiocarbon dating of bones and teeth developed by Harold Krueger and others during the 1960s laid the groundwork for subsequent research on stable carbon, nitrogen, oxygen, and strontium isotope analysis. We first review salient points

Stanley H. Ambrose; John Krigbaum

2003-01-01

101

Osteoporosis: The Bone Thief  

MedlinePLUS

... Your doctor may suggest a type of bone density test called a DXA test (dual-energy x-ray absorptiometry) if you are a woman age 65 or older or if he or she thinks you are at risk for ... show that you have normal bone density. Or, it could show that you have low ...

102

Ultrasonic bone densitometer  

NASA Technical Reports Server (NTRS)

A device, for measuring the density of a bone structure so as to monitor the calcium content, is described. A pair of opposed spaced ultrasonic transducers are held within a clamping apparatus closely adjacent the bone being analyzed. These ultrasonic transducers incude piezoelectric crystals shaped to direct signals through the bone encompassed in the heel and finger of the subject being tested. A pulse generator is coupled to one of the transducers and generates an electric pulse for causing the transducers to generate an ultrasonic sound wave which is directed through the bone structure to the other transducer. An electric circuit, including an amplifier and a bandpass filter couples the signals from the receiver transducer back to the pulse generator for retriggering the pulse generator at a frequency proportional to the duration that the ultrasonic wave takes to travel through the bone structure being examined.

Hoop, J. M. (inventor)

1974-01-01

103

Gallium scintigraphy in bone infarction. Correlation with bone imaging  

SciTech Connect

The appearance of gallium-67 images in bone infarction was studied in nine patients with sickle cell disease and correlated with the bone scan findings. Gallium uptake in acute infarction was decreased or absent with a variable bone scan uptake, and normal in healing infarcts, which showed increased uptake on bone scan. The significance of these findings is discussed.

Armas, R.R.; Goldsmith, S.J.

1984-01-01

104

Induced healing of aneurysmal bone cysts by demineralized bone particles  

Microsoft Academic Search

Two cases of induced healing of aneurysmal bone cyst (ABC) following intralesional implantation of a bone paste made of autogeneic bone marrow and allogeneic bone powder are reported. The calcaneum in one case and the superior pubic ramus in the other were blown out by an ABC and would have required extensive surgery. Via a minimal exposure, the cyst was

C. Delloye; P. Nayer; J. Malghem; H. Noel

1996-01-01

105

Osteopontin deficiency increases bone fragility but preserves bone mass Philipp J. Thurner a,b  

E-print Network

Osteopontin deficiency increases bone fragility but preserves bone mass Philipp J. Thurner a contribute to bone fragility. © 2010 Elsevier Inc. All rights reserved. Introduction Currently, bone mineral

Ritchie, Robert

106

SILICON AND BONE HEALTH  

PubMed Central

Low bone mass (osteoporosis) is a silent epidemic of the 21st century, which presently in the UK results in over 200,000 fractures annually at a cost of over one billion pounds. Figures are set to increase worldwide. Understanding the factors which affect bone metabolism is thus of primary importance in order to establish preventative measures or treatments for this condition. Nutrition is an important determinant of bone health, but the effects of the individual nutrients and minerals, other than calcium, is little understood. Accumulating evidence over the last 30 years strongly suggest that dietary silicon is beneficial to bone and connective tissue health and we recently reported strong positive associations between dietary Si intake and bone mineral density in US and UK cohorts. The exact biological role(s) of silicon in bone health is still not clear, although a number of possible mechanisms have been suggested, including the synthesis of collagen and/or its stabilization, and matrix mineralization. This review gives an overview of this naturally occurring dietary element, its metabolism and the evidence of its potential role in bone health. PMID:17435952

JUGDAOHSINGH, R.

2009-01-01

107

Microwave drilling of bones.  

PubMed

This paper presents a feasibility study of drilling in fresh wet bone tissue in vitro using the microwave drill method [Jerby et al, 2002], toward testing its applicability in orthopaedic surgery. The microwave drill uses a near-field focused energy (typically, power under approximately 200 W at 2.45-GHz frequency) in order to penetrate bone in a drilling speed of approximately 1 mm/s. The effect of microwave drilling on mechanical properties of whole ovine tibial and chicken femoral bones drilled in vitro was studied using three-point-bending strength and fatigue tests. Properties were compared to those of geometrically similar bones that were equivalently drilled using the currently accepted mechanical rotary drilling method. Strength of mid-shaft, elastic moduli, and cycles to failure in fatigue were statistically indistinguishable between specimen groups assigned for microwave and mechanical drilling. Carbonized margins around the microwave-drilled hole were approximately 15% the hole diameter. Optical and scanning electron microscopy studies showed that the microwave drill produces substantially smoother holes in cortical bone than those produced by a mechanical drill. The hot spot produced by the microwave drill has the potential for overcoming two major problems presently associated with mechanical drilling in cortical and trabecular bone during orthopaedic surgeries: formation of debris and rupture of bone vasculature during drilling. PMID:16761844

Eshet, Yael; Mann, Ronit Rachel; Anaton, Abby; Yacoby, Tomer; Gefen, Amit; Jerby, Eli

2006-06-01

108

Mimicking the nanostructure of bone matrix to regenerate bone  

PubMed Central

Key features of bone tissue structure and composition are capable of directing cellular behavior towards the generation of new bone tissue. Bone tissue, as well as materials derived from bone, have a long and successful history of use as bone grafting materials. Recent developments in design and processing of synthetic scaffolding systems has allowed the replication of the bone’s desirable biological activity in easy to fabricate polymeric materials with nano-scale features exposed on the surface. The biological response to these new tissue-engineering scaffold materials oftentimes exceeds that seen on scaffolds produced using biological materials. PMID:24688283

Kane, Robert; Ma1, Peter X.

2014-01-01

109

Osteoinduction by demineralised bone  

Microsoft Academic Search

Summary.  \\u000a Bone contains several growth factors, including bone morphogenetic proteins (BMPs), transforming growth factor beta (TGF-?),\\u000a insulin-like growth factors I and II (IGF-I and IGF-II), platelet derived growth factor (PDGF) and basic and acidic fibroblast\\u000a growth factor (bFGF and aFGF). The BMPs are the only factors known to provoke bone formation heterotopically by making undifferentiated\\u000a mesenchymal cells differentiate into osteoblasts

E. Solheim

1998-01-01

110

Bone graft substitutes.  

PubMed

Replacement of missing bone stock is a reconstructive challenge to upper extremity surgeons and decision-making with regards to available choices remains difficult. Preference is often given to autograft in the form of cancellous, cortical, or corticocancellous grafts from donor sites. However, the available volume from such donor sites is limited and fraught with potential complications. Advances in surgical management and medical research have produced a wide array of potential substances that can be used for bone graft substitute. Considerations in selecting bone grafts and substitutes include characteristic capabilities, availability, patient morbidity, immunogenicity, potential disease transmission, and cost variability. PMID:23101596

Bhatt, Reena A; Rozental, Tamara D

2012-11-01

111

Aspergillosis of the bone.  

PubMed

Aspergillosis of the long bones has not been reported. Those of the bones of the paranasal sinuses and ear canal have been reported but rare. A young woman reported to us with history of discharging sinuses around the right knee and recent fracture of the right femur. Despite all efforts, she ended up losing the whole limb from the hip. When a patient with Aspergillosis of the long bones presents late, amputation may be the best option. Early diagnosis will prevent this. PMID:25567698

Dabkana, T M; Pindiga, Umaru H; Mayun, Ahmed A; Nggada, Haruna A

2015-01-01

112

Validation of Bone Conversion in Osteoconductive and Osteoinductive Bone Substitutes  

Microsoft Academic Search

Bone reconstruction can be performed with an autogeneic graft from various donor regions. Osteoconductive and osteoinductive\\u000a bone substitutes originate from substances of diverse chemical and morphological types and can have a synthetic or a biological\\u000a derivation. Alongside autogeneic bone transplants and allogenic and xenogeneic bone implants, alloplastic bone replacements\\u000a of synthetic or semi-synthetic origin are being used for defect reconstruction.

Frank Soost; Stefan Koch; Christian Stoll; Holger Amthauer; Christian Große-Siestrup; Paul Zorn

2001-01-01

113

Bone Grafts in Craniofacial Surgery  

PubMed Central

Reconstruction of cranial and maxillofacial defects is a challenging task. The standard reconstruction method has been bone grafting. In this review, we shall describe the biological principles of bone graft healing, as pertinent to craniofacial reconstruction. Different types and sources of bone grafts will be discussed, as well as new methods of bone defect reconstruction. PMID:22110806

Elsalanty, Mohammed E.; Genecov, David G.

2009-01-01

114

Bone Cancer: Questions and Answers  

MedlinePLUS

... Are there different types of primary bone cancer? Yes. Cancer can begin in any type of bone tissue. Bones are made up ... follow-up treatment necessary? What does it involve? Yes. Bone cancer ... and should report any unusual symptoms right away. Follow-up varies for ...

115

Bone pain or tenderness  

MedlinePLUS

... cause of the pain, your doctor may prescribe: Antibiotics Anti-inflammatory medicines Hormones Laxatives (if you develop constipation during prolonged bed rest) Pain relievers If pain is related to thinning bones, you may need treatment for osteoporosis .

116

Metabolic Bone Diseases  

Microsoft Academic Search

\\u000a The current chapter provides an overview of the important imaging features observed in metabolic bone diseases [1, 2]. Common and uncommon imaging findings observed in insufficiency stress fractures are reviewed and illustrated.

BrunoVande Berg; Frederic Lecouvet; Paolo Simoni; Jacques Malghem

117

Metastatic Bone Disease  

MedlinePLUS

... that occurs without activity (i.e., walking or li ing an object) is particularly concerning. Diagnosis Medical ... with metastatic bone disease. In select cases, a computerized tomography (CT) scan and/or magnetic resonance image ( ...

118

Bone healing and osteoporosis.  

PubMed

A correct fracture healing depends on the synergy between biomechanical, molecular and cellular factors. Focusing on different stages, fracture hematoma represents the starting point of the inflammatory process, with a critical role in triggering the process of fracture healing. The essential factors for bone repair are the activation of mesenchymal stem cells and the release of growth and regulatory factors. Moreover, the efficacy of fracture healing is determined by three ideal conditions: adequate blood supply, good contact between bone fragments and good stability. It is remarkable how the implant choice influences fracture healing after surgical treatment. In osteoporosis, bone quality adversely affects the tissue structural competence, increasing the risk of a complicated fracture healing. The qualitative and quantitative alterations established at the cellular level during osteoporosis explain the progressive deterioration of bone tissue healing ability. PMID:21970927

Tarantino, Umberto; Cerocchi, Irene; Scialdoni, Alessandro; Saturnino, Luca; Feola, Maurizio; Celi, Monica; Liuni, Federico Maria; Iolascon, Giovanni; Gasbarra, Elena

2011-04-01

119

Fossilized Dinosaur Bones  

NSDL National Science Digital Library

This slide show presents images of dinosaur bones and shows paleotologists at work excavating and preserving these fossils, the best evidence remaining of these long-lost creatures. A background essay and discussion questons are included.

120

Vitamin D and Bone  

PubMed Central

All cells comprising the skeleton—chondrocytes, osteoblasts, and osteoclasts—contain both the vitamin D receptor and the enzyme CYP27B1 required for producing the active metabolite of vitamin D, 1,25 dihydroxyvitamin D. Direct effects of 25 hydroxyvitamin D and 1,25 dihydroxyvitamin D on these bone cells have been demonstrated. However, the major skeletal manifestations of vitamin D deficiency or mutations in the vitamin D receptor and CYP27B1, namely rickets and osteomalacia, can be corrected by increasing the intestinal absorption of calcium and phosphate, indicating the importance of indirect effects. On the other hand, these dietary manipulations do not reverse defects in osteoblast or osteoclast function that lead to osteopenic bone. This review discusses the relative importance of the direct versus indirect actions of vitamin D on bone, and provides guidelines for the clinical use of vitamin D to prevent/treat bone loss and fractures. PMID:22544628

2013-01-01

121

Bone mineral crystallisation kinetics.  

PubMed

The kinetics of bone apatite crystallisation are examined using a novel approach to obtain quantitative, direction dependence features such as growth rate and activation energy. X-ray diffraction was employed for analysis of bovine, porcine and 'anorganic' bone specimens. Apatite coherence length was utilised as the independent variable within a Johnson-Mehl-Avrami (JMA) model. A direction averaged crystallisation activation energy of 183 ± 8 kJ mol(-1) was observed for the three bone groups. The Johnson-Mehl-Avrami 'n' exponent decreased with increasing temperature for all bone groups, indicating that apatite crystallisation changes to a diffusion limited process at higher temperatures. The results revealed little evidence to support any organic component 'protective' effect, and, on the contrary indicated that the organic matrix promotes apatite crystallisation. PMID:22743865

Greenwood, C; Rogers, K; Beckett, S; Clement, J

2012-09-01

122

The Geometry of the Bone Structure Associated with Total Hip Arthroplasty  

PubMed Central

Close adaptation of the prosthesis to the bone is the key to achieving optimal stability and fixation for total hip arthroplasty (THA). However, there have been no adequate studies of bone morphology, especially in different races. The aim of this study was to analyze the geometry of the acetabulum and proximal femur of people from South China, based on three-dimensional reconstruction, and to detect differences between different population subsets. CT scans were performed on 80 healthy volunteers (160 hips) from South China, comprising 40 males (80 hips) and 40 females (80 hips). The images were imported into Mimics 10.01 to perform 3D reconstruction. THA-associated anatomical parameters were measured and compared with other published data. In comparison with published data, it seemed that people from South China have smaller acetabular abduction angle, larger acetabular supro-inferior diameter, larger neck-shaft angle, smaller offset, thinner femoral shaft and more proximal isthmus, which needed to be further confirmed. There were significant differences between the genders in most parameters. As significant differences in canal flare index (CFI) and distal canal flare index (DCFI) were found between genders, it was concluded the most significant differences lay in the isthmus of the femur. Among the femora, according to Noble’s classification we identified more normal types and fewer stovepipe and champagne-flute types than expected from the literature, indicating that uncemented prostheses would be suitable for most people from South China. Our findings reveal that simply choosing the smallest of a series of prostheses would not necessarily provide a good fit, due to the different trends from the proximal to the distal part of the femur. Significant variation exists in THA-associated anatomy between genders and population subsets. It is therefore imperative that each patient receives individual consideration rather than assuming all patients have the same anatomy, especially for different races. PMID:24608343

Yang, Zhang; Jian, Wang; Zhi-han, Li; Jun, Xiao; Liang, Zhao; Ge, Yan; Zhan-jun, Shi

2014-01-01

123

Metabolic Bone Disease  

Microsoft Academic Search

\\u000a Metabolic bone disease may result from genetic, endocrine, nutritional, or biochemical disorders, with variable and often\\u000a inconsistent imaging findings. For the radiologist, the cornerstone of “metabolic bone disease” has been osteoporosis, osteomalacia,\\u000a hyperparathyroidism, and Paget’s disease. Over the past three decades, the diagnosis and therapy of these diseases has changed,\\u000a influenced by biochemical discoveries, imaging advances, and epidemiology studies that

Murali Sundaram

124

Automated bone fracture detection  

NASA Astrophysics Data System (ADS)

Fractures of bone are a common affliction. In most developed countries the number of fractures associated with age-related bone loss is increasing rapidly. Each year many fractures are missed during x-ray diagnosis, resulting in ineffective patient management and expensive litigation. From both an orthopaedic and radiologic point of view, the fully automatic detection and classification of fractures in long-bones is an important but difficult problem. In this paper, a fully automated method of detecting fractures in the diaphysis of a long-bone is described. X-rays are very difficult to process automatically, so to extract the required information a non-linear anisotropic diffusion method, the Affine Morphological Scale Space, was implemented to smooth the image without losing information about the location of boundaries within the image. Next, an iterative peak detection algorithm is used to accurately locate the bone centreline and articular surfaces. A method based on orthogonal projections calculated from a modified Hough transform is used to automatically locate the long-bone diaphysis. At this point, our algorithm accurately localises the area of the fracture, and would allow further image registration if necessary. Finally, a gradient-based algorithm is used to detect fractures present in the region of interest. The magnitude and direction of the gradient are combined to produce a measure of the likelyhood of the presence of a fracture. A library of long-bone fracture images was created. Experimental tests performed on a series of x-ray images show that the method is capable of accurately segmenting the diaphysis from the epiphyses, and is also able to detect many mid-shaft fractures of long-bones.

Donnelley, Martin; Knowles, Greg

2005-04-01

125

Bone marrow edema syndrome  

Microsoft Academic Search

Bone marrow edema syndrome (BMES) refers to transient clinical conditions with unknown pathogenic mechanism, such as transient\\u000a osteoporosis of the hip (TOH), regional migratory osteoporosis (RMO), and reflex sympathetic dystrophy (RSD). BMES is primarily\\u000a characterized by bone marrow edema (BME) pattern. The disease mainly affects the hip, the knee, and the ankle of middle-aged\\u000a males. Many hypotheses have been proposed

Anastasios V. Korompilias; Apostolos H. Karantanas; Marios G. Lykissas; Alexandros E. Beris

2009-01-01

126

Strontium ranelate inhibits bone resorption while maintaining bone formation in alveolar bone in monkeys ( Macaca fascicularis)  

Microsoft Academic Search

Strontium ranelate (S12911) has previously been shown to stimulate bone formation and inhibit bone resorption in rats. To determine whether strontium ranelate affects normal bone remodeling, we studied the effect of strontium ranelate on alveolar bone in monkeys. Strontium ranelate, at dosages of 100, 275, and 750 mg\\/kg per day, or vehicle, were given by gavage to 31 normal adult

J Buehler; P Chappuis; J. L Saffar; Y Tsouderos; A Vignery

2001-01-01

127

Boning up on autophagy  

PubMed Central

From an evolutionary perspective, the major function of bone is to provide stable sites for muscle attachment and affording protection of vital organs, especially the heart and lungs (ribs) and spinal cord (vertebrae and intervertebral discs). However, bone has a considerable number of other functions: serving as a store for mineral ions, providing a site for blood cell synthesis and participating in a complex system-wide endocrine system. Not surprisingly, bone and cartilage cell homeostasis is tightly controlled, as is the maintenance of tissue structure and mass. While a great deal of new information is accruing concerning skeletal cell homeostasis, one relatively new observation is that the cells of bone (osteoclasts osteoblasts and osteocytes) and cartilage (chondrocytes) exhibit autophagy. The focus of this review is to examine the significance of this process in terms of the functional demands of the skeleton in health and during growth and to provide evidence that dysregulation of the autophagic response is involved in the pathogenesis of diseases of bone (Paget disease of bone) and cartilage (osteoarthritis and the mucopolysaccharidoses). Delineation of molecular changes in the autophagic process is uncovering new approaches for the treatment of diseases that affect the axial and appendicular skeleton. PMID:24225636

Shapiro, Irving M; Layfield, Robert; Lotz, Martin; Settembre, Carmine; Whitehouse, Caroline

2014-01-01

128

Bone nutrients for vegetarians.  

PubMed

The process of bone mineralization and resorption is complex and is affected by numerous factors, including dietary constituents. Although some dietary factors involved in bone health, such as calcium and vitamin D, are typically associated with dairy products, plant-based sources of these nutrients also supply other key nutrients involved in bone maintenance. Some research suggests that vegetarian diets, especially vegan diets, are associated with lower bone mineral density (BMD), but this does not appear to be clinically significant. Vegan diets are not associated with an increased fracture risk if calcium intake is adequate. Dietary factors in plant-based diets that support the development and maintenance of bone mass include calcium, vitamin D, protein, potassium, and soy isoflavones. Other factors present in plant-based diets such as oxalic acid and phytic acid can potentially interfere with absorption and retention of calcium and thereby have a negative effect on BMD. Impaired vitamin B-12 status also negatively affects BMD. The role of protein in calcium balance is multifaceted. Overall, calcium and protein intakes in accord with Dietary Reference Intakes are recommended for vegetarians, including vegans. Fortified foods are often helpful in meeting recommendations for calcium and vitamin D. Plant-based diets can provide adequate amounts of key nutrients for bone health. PMID:24898231

Mangels, Ann Reed

2014-06-01

129

Bone scans in neuroblastoma.  

PubMed

Eighty-Six patients of neuroblastoma ranging in age from four months to 15 years were studied with 99m Tc-MDP for total skeletal survey over a period of seven years (1983-1990). The diagnosis of neuroblastoma was based on bone marrow examination, FNAC, lymph node biopsy, histopathology. Bone imaging was performed three hrs. after intravenous administration of 99m Tc-MDP. Out of 86 patients, 45 patients had positive bone scan showing osseous concentration in 122 sites and extraosseous concentration in 34 sites. Seven patients had liver metastases. None of these liver metastases showed concentration of MDP. Fourteen patients underwent surgery for the primary tumour at the time of bone scanning. Ten patients were studied at the time of follow up, of which four patients showed good response as bony metastases were not demonstrated on bone scintigraphy and X-rays. In conclusion, bone scan is an useful test in neuroblastoma in delineating the bony metastases and also in assessing the efficacy of chemotherapy in these patients. PMID:8500809

Bhogate, B M; Samuel, A M; Ramanathan, P

1993-03-01

130

Bone quality. Roentgenographic versus histologic assessment of hip bone structure.  

PubMed

Bone quality is an accepted criterion for determining fixation options for total hip arthroplasty (THA). Eighty patients with 95 uncemented THAs were evaluated by comparing preoperative roentgenographic assessment with histologic evaluation of bone biopsy specimens obtained from the ipsilateral iliac crest. Roentgenographic analysis of bone quality was performed using the Singh and Engh indices. Histologic evaluation employed a quantitative analysis of static and dynamic parameters of bone turnover on undecalcified sections. Extensive statistical analysis comparing roentgenographic with histologic parameters of bone quality showed: (1) no relationship of the two roentgenographic indices to trabecular bone volume and most other histologic parameters and (2) a high incidence of bone abnormalities. Bone quality is an imprecise term and is inadequately measured by these roentgenographic indices. Histologic measurement offers a more precise means of analyzing the relationship of the bone environment to the performance of the THA. PMID:2645075

Stulberg, B N; Bauer, T W; Watson, J T; Richmond, B

1989-03-01

131

Porous Surface Modified Bioactive Bone Cement for Enhanced Bone Bonding  

PubMed Central

Background Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. Materials and Methods The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant–bone interface was also investigated by push-out tests. Results The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony defect. Conclusions Our findings suggested a new bioactive bone cement for prosthetic fixation in total joint replacement. PMID:22905143

Huang, Li; Dong, Jingjing; Guo, Dagang; Mao, Mengmeng; Kong, Liang; Li, Yang; Wu, Zixiang; Lei, Wei

2012-01-01

132

Bone metastases: When and how lung cancer interacts with bone  

PubMed Central

Bone metastasis is a common and debilitating consequence of lung cancer: 30%-40% of patients with non-small cell lung cancer develop bone metastases during the course of their disease. Lung cancer cells find a favorable soil in the bone microenvironment due to factors released by the bone matrix, the immune system cells, and the same cancer cells. Many aspects of the cross-talk among lung tumor cells, the immune system, and bone cells are not clear, but this review aims to summarize the recent findings in this field, with particular attention to studies conducted to identify biomarkers for early detection of lung cancer bone metastases. PMID:24829862

Roato, Ilaria

2014-01-01

133

Zoledronate reduces unwanted bone resorption in intercalary bone allografts  

Microsoft Academic Search

Bone allografts are often hampered by graft incorporation and poor host bone formation. Bisphosphonates, synthetic pyrophosphate\\u000a analogs, have shown promise in inhibiting bone resorption in human and animal trials. Some in vitro studies have suggested that high dose bisphosphonate may also inhibit bone formation, leading to our hypothesis that an ideal\\u000a dose of bisphosphonate in allografts could protect allografts from

Sung W. Seo; Samuel K. Cho; Steven K. Storer; Francis Y. Lee

2010-01-01

134

Leiomyosarcoma of Bone Arising in Association with a Bone Infarct  

PubMed Central

Both primary leiomyosarcoma of bone and sarcoma arising in association with a bone infarct are rare events. In this case report we describe for the first time a case of leiomyosarcoma arising in a bone infarct. The tumour arose in a medullary infarct in the proximal femur of an elderly patient. As in other cases of sarcoma arising in a bone infarct, the prognosis was poor, the patient dying within 6 months of diagnosis. PMID:18521345

Petra, M.; Gibbons, C. L. M. H.

2002-01-01

135

Alveolar bone grafting.  

PubMed

In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft. PMID:19884665

Lilja, Jan

2009-10-01

136

Invest in Your Bones Bone Mineral Calcium and Vitamin D  

E-print Network

Invest in Your Bones Bone Mineral Calcium and Vitamin D Leaflet 4 One common misconception is that calcium is only needed for growing children. In reality, both calcium and vitamin D are needed to maintain of calcium from your bones. Vitamin D promotes the absorption of calcium in the gut, which is necessary

137

Growth factors in bone  

Microsoft Academic Search

Summary.  \\u000a Bone contains several growth factors, including bone morphogenetic proteins (BMPs), transforming growth factor beta (TGF-?),\\u000a insulin-like growth factors I and II (IGF-I and IGF-II), platelet derived growth factor (PDGF) and basic and acidic fibroblast\\u000a growth factor (bFGF and aFGF). Spatial and temporal variations in the expression and secretion of the various growth factors\\u000a have been demonstrated in osteoblastic cultures

E. Solheim

1998-01-01

138

Bone Density Challenge Introduction  

NSDL National Science Digital Library

Students are introduced to the challenge question, which revolves around proving that a cabinet x-ray system can produce bone mineral density images. Students work independently to generate ideas from the questions provided, then share with partners and then with the class as part of the Multiple Perspectives phase of this unit. Then, as part of the associated activity, students explore multiple websites to gather information about bone mineral density and answer worksheet questions, followed by a quiz on the material covered in the articles.

Vu Bioenegineering Ret Program

139

[Advances in bone dysplasias].  

PubMed

The prevalence of bone dysplasias is estimated to be one case per 1,000 inhabitants, which suggests that, at some point in the career of an orthopaedic surgeon, he will face with one of these patients. The aim of this paper is to review the general aspects of bone dysplasias and focus on those, which due to their frequency and importance, we consider most relevant (achondroplasia, multiple epiphyseal dysplasia, spondyloepiphyseal dysplasia, osteogenesis imperfecta), reviewing their fundamental features and the latest therapeutic advances. There is no cure for these diseases, so early diagnosis and appropriate therapeutic management, becomes the key to improving quality of life of these patients. PMID:24731388

Borrego, E; Farrington, D M; Downey, F J

2014-01-01

140

Implant fixation by bone ingrowth.  

PubMed

The term osseointegration referred originally to an intimate contact of bone tissue with the surface of a titanium implant; the term bone ingrowth refers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historical background describes the development of macroporous, microporous, and textured surfaces with an emphasis on the evolution of porous and textured metal surfaces. The principal requirements for osseointegration and bone ingrowth are systematically reviewed as follows: i) the physiology of osseointegration and bone ingrowth, including biomaterial biocompatibility with respect to cellular and matrix response at the interface; ii) the implant surface geometry characteristics; iii) implant micromotion and fixation modes; and iv) the implant-bone interface distances. Based on current methods of bone ingrowth assessment, this article comparatively reviews and discusses the results of experimental studies with the objective of determining local and systemic factors that enhance bone ingrowth fixation. PMID:10220191

Kienapfel, H; Sprey, C; Wilke, A; Griss, P

1999-04-01

141

Vitamin A and Bone Health  

MedlinePLUS

... supported by your browser. Home Bone Basics Nutrition Vitamin A and Bone Health Publication available in: PDF (236 KB) Related Resources Calcium and Vitamin D El calcio y la vitamina D (Calcium ...

142

Graphite-reinforced bone cement  

NASA Technical Reports Server (NTRS)

Chopped graphite fibers added to surgical bone cement form bonding agent with mechanical properties closely matched to those of bone. Curing reaction produces less heat, resulting in reduced traumatization of body tissues. Stiffness is increased without affecting flexural strength.

Knoell, A. C.

1976-01-01

143

Exercise for Your Bone Health  

MedlinePLUS

... supported by your browser. Home Bone Basics Lifestyle Exercise for Your Bone Health Publication available in: PDF ( ... ??) Related Resources Alcoholism Bed Rest and Immobilization Exercise and Osteogenesis Imperfecta Overtraining Risks for Women Oral ...

144

Pattern Alteration: Protruding Hip Bone  

E-print Network

People with very thin figures typically have to alter their clothing for protruding hip bones. This is because diagonal wrinkles radiate from the hip bones. This well-illustrated publication shows how to correct this problem in pants and skirts....

2006-08-04

145

Oral Health and Bone Disease  

MedlinePLUS

... Size | S S M M L L Bone Basics Osteoporosis Osteogenesis Imperfecta Paget?s Disease of Bone Related Topics News Glossary ... Rest and Immobilization Exercise Exercise (??) Exercise and Osteogenesis Imperfecta Overtraining Risks for Women Smoking Partner Resources Oral ...

146

Bone and cancer: the osteoncology  

PubMed Central

Summary In recent years clinicians have witnessed a radical change in the relationship between bone and cancer, with in particular an increase in bone metastases incidence due to an improvement of patients survival. Bone metastases are responsible for the high morbidity in cancer patients with a strong clinical impact. For all these reasons, efforts have been directed to this important field with the foundation of the osteoncology, a new scientific and clinical branch involved in the management of patients with bone cancer disease, including primary bone tumors and bone metastases. Another innovative and important osteoncology topic is the Cancer Treatment Induced Bone Loss (CTIBL) that is mainly caused by antitumoral treatment with bone resorption induction. The diagnostic and therapeutic options are described briefly in order to highlight the importance of the multidisciplinary approach in this new field. PMID:24133529

Ibrahim, Toni; Mercatali, Laura; Amadori, Dino

2013-01-01

147

Aspiration and Biopsy: Bone Marrow  

MedlinePLUS

... a bone marrow sample for procedures (such as stem cell transplantation ) or other testing (such as chromosomal analysis). ... For the bone marrow aspiration, the doctor or nurse will carefully insert a needle into the biopsy ...

148

Cutting thin sections of bone  

NASA Technical Reports Server (NTRS)

Medical equipment for obtaining repetitive planoparallel sections of bone to study healing of bone structure under high gravity stress is described. Device consists of modified saw with diamond cutting edges. Construction of device and manner of use are explained.

Ashley, W. W.

1972-01-01

149

Spinal bone graft - series (image)  

MedlinePLUS

... is made over the bone defect, and the bone graft is shaped around and inserted into the defect. The graft is held in place with pins, plates, or screws. The incisions are stitched (sutured) closed. A splint ...

150

A soluble bone morphogenetic protein type IA receptor increases bone mass and bone strength  

PubMed Central

Diseases such as osteoporosis are associated with reduced bone mass. Therapies to prevent bone loss exist, but there are few that stimulate bone formation and restore bone mass. Bone morphogenetic proteins (BMPs) are members of the TGF? superfamily, which act as pleiotropic regulators of skeletal organogenesis and bone homeostasis. Ablation of the BMPR1A receptor in osteoblasts increases bone mass, suggesting that inhibition of BMPR1A signaling may have therapeutic benefit. The aim of this study was to determine the skeletal effects of systemic administration of a soluble BMPR1A fusion protein (mBMPR1A–mFc) in vivo. mBMPR1A–mFc was shown to bind BMP2/4 specifically and with high affinity and prevent downstream signaling. mBMPR1A–mFc treatment of immature and mature mice increased bone mineral density, cortical thickness, trabecular bone volume, thickness and number, and decreased trabecular separation. The increase in bone mass was due to an early increase in osteoblast number and bone formation rate, mediated by a suppression of Dickkopf-1 expression. This was followed by a decrease in osteoclast number and eroded surface, which was associated with a decrease in receptor activator of NF-?B ligand (RANKL) production, an increase in osteoprotegerin expression, and a decrease in serum tartrate-resistant acid phosphatase (TRAP5b) concentration. mBMPR1A treatment also increased bone mass and strength in mice with bone loss due to estrogen deficiency. In conclusion, mBMPR1A–mFc stimulates osteoblastic bone formation and decreases bone resorption, which leads to an increase in bone mass, and offers a promising unique alternative for the treatment of bone-related disorders. PMID:22761317

Baud’huin, Marc; Solban, Nicolas; Cornwall-Brady, Milton; Sako, Dianne; Kawamoto, Yoshimi; Liharska, Katia; Lath, Darren; Bouxsein, Mary L.; Underwood, Kathryn W.; Ucran, Jeffrey; Kumar, Ravindra; Pobre, Eileen; Grinberg, Asya; Seehra, Jasbir; Canalis, Ernesto; Pearsall, R. Scott; Croucher, Peter I.

2012-01-01

151

Dental Applications of Bone Biology  

Microsoft Academic Search

The teeth are implanted in depressions within alveolar bone and are surrounded by the periodontium which consists of bone,\\u000a a suspensory ligament (the periodontal ligament), cementum on the root surface, and gingiva. In health, the bone tissue is\\u000a located approximately 2 mm below the cementoenamel junction which separates the crown of the tooth and its root from the bone\\u000a (Fig.

Thomas W. Oates; David L. Cochran

152

New Imaging Modalities in Bone  

Microsoft Academic Search

The digital era has witnessed an exponential growth in bone imaging as new modalities and analytic techniques improve the\\u000a potential for noninvasive study of bone anatomy, physiology, and pathophysiology. Bone imaging very much lends itself to input\\u000a across medical and engineering disciplines. It is in part a reflection of this multidisciplinary input that developments in\\u000a the field of bone imaging

James F. Griffith; Harry K. Genant

2011-01-01

153

The clinical application of bone mineral analysis  

Microsoft Academic Search

Photon absorptiometry provides an accurate measurement of bone mineral content. In acromegaly, the bone mineral content is normal, whereas the bone mineral content is reduced by acidosis. Decreased bone mineral content occurs in alcoholics due to osteomalacia and also in anticonvulsant therapy for the same reason. In hyperparathyroidism, there is decreased bone mineral content. Corticosteroids reduce bone mineral content especially

Harry J. Griffiths; Robert E. Zimmerman

1978-01-01

154

Implant fixation by bone ingrowth  

Microsoft Academic Search

The term osseointegration referred originally to an intimate contact of bone tissue with the surface of a titanium implant; the term bone ingrowth refers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historical background describes the development of macroporous, microporous, and textured surfaces with an emphasis

H. Kienapfel; C. Sprey; A. Wilke; P. Griss

1999-01-01

155

Bone augmentation with TiMesh. autologous bone versus autologous bone and bone substitutes. A systematic review  

PubMed Central

Summary Aim of the study Reconstruction of segmental defects and the atrophic maxilla and mandible is performed using various techniques. Bone substitutes have received a wealth of reports in the literature demonstrating a long-term success when used in alveolar bone augmentation procedures. Materials and methods We reviewed articles comparing TiMesh GBR technique with different percentage of bone: autogenous bone alone (AB); anorganic bovine bone alone (ABB); 50:50 or 70:30. From an initial pool of 122, we selected 14 studies. ANOVA followed by Tukey HSD test was used for statistical analysis. Results We present a table analysing fundamental parameters to value a successful GBR therapy. Autogenous bone remains the gold standard in GBR technique with TiMesh; however, the combination between AB/ABB in relation 50:50 and 70:30 allows reducing surgical cost exploiting properties of eterologous bone. Conclusion The use of autologous bone is associated with a height and width gain of bone, which are greater compared to other techniques, with a lower exposure of the mesh and a lower bone resorption. The use of heterologous graft leads to a lower bone earn and to percentage of resorption greater than autologous graft but does not differ from the gain and resorption of the bone of AB/ABB in percentage 50:50 and 70:30.

Carini, Fabrizio; Longoni, Salvatore; Amosso, Ernesto; Paleari, Jacopo; Carini, Stefania; Porcaro, Gianluca

2014-01-01

156

Scaffold Design for Bone Regeneration  

PubMed Central

The use of bone grafts is the standard to treat skeletal fractures, or to replace and regenerate lost bone, as demonstrated by the large number of bone graft procedures performed worldwide. The most common of these is the autograft, however, its use can lead to complications such as pain, infection, scarring, blood loss, and donor-site morbidity. The alternative is allografts, but they lack the osteoactive capacity of autografts and carry the risk of carrying infectious agents or immune rejection. Other approaches, such as the bone graft substitutes, have focused on improving the efficacy of bone grafts or other scaffolds by incorporating bone progenitor cells and growth factors to stimulate cells. An ideal bone graft or scaffold should be made of biomaterials that imitate the structure and properties of natural bone ECM, include osteoprogenitor cells and provide all the necessary environmental cues found in natural bone. However, creating living tissue constructs that are structurally, functionally and mechanically comparable to the natural bone has been a challenge so far. This focus of this review is on the evolution of these scaffolds as bone graft substitutes in the process of recreating the bone tissue microenvironment, including biochemical and biophysical cues. PMID:24730250

Polo-Corrales, Liliana; Latorre-Esteves, Magda; Ramirez-Vick, Jaime E.

2014-01-01

157

Bone vascularization: a way to study bone microarchitecture?  

NASA Astrophysics Data System (ADS)

Trabecular bone and its microarchitecture are of prime importance for health. Studying vascularization helps to better know the relationship between bone and vascular microarchitecture. This research is an animal study (nine Lewis rats), based on the perfusion of vascularization by a contrast agent (a mixture of 50% barium sulfate with 1.5% of gelatin) before euthanasia. The samples were studied by micro CT at a resolution of 9?m. Softwares were used to show 3D volumes of bone and vessels, to calculate bone and vessels microarchitecture parameters. This study aims to understand simultaneously the bone microarchitecture and its vascular microarchitecture.

Blery, P.; Autrusseau, F.; Crauste, E.; Freuchet, Erwan; Weiss, Pierre; Guédon, J.-P.; Amouriq, Y.

2014-03-01

158

Are bones alive?  

Microsoft Academic Search

Many studies have investigated the classification of living things. Our study deals with a different problem: the attribution of life to one component of a living organism, specifically the bones. The task involves not only specifying what we mean by ‘alive’, but also requires ‘informed thinking’ leading to an understanding of the concept of life itself. This study is part

Silvia Caravita; Elisabetta Falchetti

2005-01-01

159

Bones Surgery Codes  

Cancer.gov

Bones, Joints, And Articular Cartilage C400–C419 Peripheral Nerves And Autonomic Nervous System C470–C479 Connective, Subcutaneous, And Other Soft Tissues C490–C499 (Except for M9727, 9733, 9741-9742, 9764-9809, 9832, 9840-9931, 9945-9946, 9950-9967,

160

Are Bones Alive?  

ERIC Educational Resources Information Center

Many studies have investigated the classification of living things. Our study deals with a different problem: the attribution of life to one component of a living organism, specifically the bones. The task involves not only specifying what we mean by "alive", but also requires "informed thinking" leading to an understanding of the concept of life…

Caravita, Silvia; Falchetti, Elisabetta

2005-01-01

161

Bone fragility: current reviews and clinical features.  

PubMed

Bone strength is determined by a number of important factors, including bone mass and bone shape. A reduction in bone strength is clearly related to fracture. Bone fragility results from a reduction in bone mass and density. If there is a reduction in the connectivity of bone and impact from a mechanical load occurs, bone will fracture. Rather than considering bone fragility as being the result of a reduced amount of bone, we recognize that bone fragility is the result of changes in the material and structural properties of bone. A better understanding of the contribution of each component of the material composition and structure, and how these interact to maintain whole bone strength is obtained by the study of metabolic bone diseases. Disorders of collagen, of mineral content composition and distribution, disorders of remodelling and other diseases produce abnormalities in the material composition and structure that lead to bone fragility. PMID:22461157

Tranquilli Leali, Paolo; Doria, Carlo; Zachos, Alexandros; Ruggiu, Adriano; Milia, Fabio; Barca, Francesca

2009-05-01

162

Bone fragility: current reviews and clinical features  

PubMed Central

Bone strength is determined by a number of important factors, including bone mass and bone shape. A reduction in bone strength is clearly related to fracture. Bone fragility results from a reduction in bone mass and density. If there is a reduction in the connectivity of bone and impact from a mechanical load occurs, bone will fracture. Rather than considering bone fragility as being the result of a reduced amount of bone, we recognize that bone fragility is the result of changes in the material and structural properties of bone. A better understanding of the contribution of each component of the material composition and structure, and how these interact to maintain whole bone strength is obtained by the study of metabolic bone diseases. Disorders of collagen, of mineral content composition and distribution, disorders of remodelling and other diseases produce abnormalities in the material composition and structure that lead to bone fragility. PMID:22461157

Tranquilli Leali, Paolo; Doria, Carlo; Zachos, Alexandros; Ruggiu, Adriano; Milia, Fabio; Barca, Francesca

2009-01-01

163

Evolutionary Patterns of Bone Histology and Bone Compactness in Xenarthran Mammal Long Bones  

PubMed Central

Bone microstructure reflects physiological characteristics and has been shown to contain phylogenetic and ecological signals. Although mammalian long bone histology is receiving increasing attention, systematic examination of the main clades has not yet been performed. Here we describe the long bone microstructure of Xenarthra based on thin sections representing twenty-two species. Additionally, patterns in bone compactness of humeri and femora are investigated. The primary bone tissue of xenarthran long bones is composed of a mixture of woven, parallel-fibered and lamellar bone. The vascular canals have a longitudinal, reticular or radial orientation and are mostly arranged in an irregular manner. Concentric rows of vascular canals and laminar organization of the tissue are only found in anteater bones. The long bones of adult specimens are marked by dense Haversian bone, a feature that has been noted for most groups of mammals. In the long bones of armadillos, secondary osteons have an oblique orientation within the three-dimensional bone tissue, thus resulting in their irregular shape when the bones are sectioned transversely. Secondary remodeling is generally more extensive in large taxa than in small taxa, and this could be caused by increased loading. Lines of arrested growth are assumed to be present in all specimens, but they are restricted to the outermost layer in bones of armadillos and are often masked by secondary remodeling in large taxa. Parameters of bone compactness show a pattern in the femur that separates Cingulata and Pilosa (Folivora and Vermilingua), with cingulates having a lower compactness than pilosans. In addition, cingulates show an allometric relationship between humeral and femoral bone compactness. PMID:23874932

Straehl, Fiona R.; Scheyer, Torsten M.; Forasiepi, Analía M.; MacPhee, Ross D.; Sánchez-Villagra, Marcelo R.

2013-01-01

164

Evolutionary patterns of bone histology and bone compactness in xenarthran mammal long bones.  

PubMed

Bone microstructure reflects physiological characteristics and has been shown to contain phylogenetic and ecological signals. Although mammalian long bone histology is receiving increasing attention, systematic examination of the main clades has not yet been performed. Here we describe the long bone microstructure of Xenarthra based on thin sections representing twenty-two species. Additionally, patterns in bone compactness of humeri and femora are investigated. The primary bone tissue of xenarthran long bones is composed of a mixture of woven, parallel-fibered and lamellar bone. The vascular canals have a longitudinal, reticular or radial orientation and are mostly arranged in an irregular manner. Concentric rows of vascular canals and laminar organization of the tissue are only found in anteater bones. The long bones of adult specimens are marked by dense Haversian bone, a feature that has been noted for most groups of mammals. In the long bones of armadillos, secondary osteons have an oblique orientation within the three-dimensional bone tissue, thus resulting in their irregular shape when the bones are sectioned transversely. Secondary remodeling is generally more extensive in large taxa than in small taxa, and this could be caused by increased loading. Lines of arrested growth are assumed to be present in all specimens, but they are restricted to the outermost layer in bones of armadillos and are often masked by secondary remodeling in large taxa. Parameters of bone compactness show a pattern in the femur that separates Cingulata and Pilosa (Folivora and Vermilingua), with cingulates having a lower compactness than pilosans. In addition, cingulates show an allometric relationship between humeral and femoral bone compactness. PMID:23874932

Straehl, Fiona R; Scheyer, Torsten M; Forasiepi, Analía M; MacPhee, Ross D; Sánchez-Villagra, Marcelo R

2013-01-01

165

Peripheral Leptin Regulates Bone Formation  

PubMed Central

Substantial evidence does not support the prevailing view that leptin, acting through a hypothalamic relay, decreases bone accrual by inhibiting bone formation. To clarify the mechanisms underlying regulation of bone architecture by leptin, we evaluated bone growth and turnover in wild type (WT) mice, leptin receptor-deficient db/db mice, leptin-deficient ob/ob mice and ob/ob mice treated with leptin. We also performed hypothalamic leptin gene therapy to determine the effect of elevated hypothalamic leptin levels on osteoblasts. Finally, to determine the effects of loss of peripheral leptin signaling on bone formation and energy metabolism, we used bone marrow (BM) from WT or db/db donor mice to reconstitute the hematopoietic and mesenchymal stem cell compartments in lethally irradiated WT recipient mice. Decreases in bone growth, osteoblast-lined bone perimeter and bone formation rate were observed in ob/ob mice and greatly increased in ob/ob mice following subcutaneous administration of leptin. Similarly, hypothalamic leptin gene therapy increased osteoblast-lined bone perimeter in ob/ob mice. In spite of normal osteoclast-lined bone perimeter, db/db mice exhibited a mild but generalized osteopetrotic-like (calcified cartilage encased by bone) skeletal phenotype and greatly reduced serum markers of bone turnover. Tracking studies and histology revealed quantitative replacement of BM cells following BM transplantation. WT mice engrafted with db/db BM did not differ in energy homeostasis from untreated WT mice or WT mice engrafted with WT BM. Bone formation in WT mice engrafted with WT BM did not differ from WT mice, whereas bone formation in WT mice engrafted with db/db cells did not differ from the low rates observed in untreated db/db mice. In summary, our results indicate that leptin, acting primarily through peripheral pathways, increases osteoblast number and activity. PMID:22887758

Turner, Russell T.; Kalra, Satya P.; Wong, Carmen P.; Philbrick, Kenneth A.; Lindenmaier, Laurence B.; Boghossian, Stephane; Iwaniec, Urszula T.

2012-01-01

166

The sinking bone syndrome?  

PubMed

Bone resorption is a known complication of cranioplasty after decompressive craniectomy (DC). A peculiar group of insidious, progressive, invalidating neurological symptoms was observed in patients presenting with incomplete resorption and abnormal mobility of the re-implanted bone. Such symptoms were similar, but with time more severe, to those encountered in the sinking flap syndrome. Are we facing a sort of Sinking Bone Syndrome? We accurately analyze these cases and review the literature. Over a 7-years period, 312 DCs were performed at our Institution. In 7 patients, headache, vertigo, gait ataxia, confusion, blurred speech, short-term memory impairment, hemiparesis, sudden loss of consciousness, and third cranial nerve palsy were observed in a time period ranging from 18 months to 5 years after cranioplasty. Clinical and neuroradiological examinations were performed to disclose the possible etiopathogenesis of this condition. Collected data showed partial resorption of the repositioned bone and its unnatural inward movements during postural changes. Bone movements were interpreted as the major cause of the symptoms. A new cranioplasty was then performed in every case, using porous hydroxyapatite in 6 patients and polyetherketone implant in the other. Full resolution of symptoms was always obtained 3 to 20 days after the second surgery. No further complications were reported. We believe that long-term follow up in patients operated on by cranioplasty after DC will be needed regularly for years after skull reconstruction and that newly appearing symptoms should never go underestimated or simply interpreted as a long-term consequence of previous brain damage. PMID:23708225

Di Rienzo, Alessandro; Iacoangeli, Maurizio; Alvaro, Lorenzo; Colasanti, Roberto; Dobran, Mauro; Di Somma, Lucia Giovanna Maria; Moriconi, Elisa; Scerrati, Massimo

2013-01-01

167

Predicting bone remodeling around tissue- and bone-level dental implants used in reduced bone width.  

PubMed

The objective of this study was to predict time-dependent bone remodeling around tissue- and bone-level dental implants used in patients with reduced bone width. The remodeling of bone around titanium tissue-level, and titanium and titanium-zirconium alloy bone-level implants was studied under 100 N oblique load for one month by implementing the Stanford theory into three-dimensional finite element models. Maximum principal stress, minimum principal stress, and strain energy density in peri-implant bone and displacement in x- and y- axes of the implant were evaluated. Maximum and minimum principal stresses around tissue-level implant were higher than bone-level implants and both bone-level implants experienced comparable stresses. Total strain energy density in bone around titanium implants slightly decreased during the first two weeks of loading followed by a recovery, and the titanium-zirconium implant showed minor changes in the axial plane. Total strain energy density changes in the loading and contralateral sides were higher in tissue-level implant than other implants in the cortical bone at the horizontal plane. The displacement values of the implants were almost constant over time. Tissue-level implants were associated with higher stresses than bone-level implants. The time-dependent biomechanical outcome of titanium-zirconium alloy bone-level implant was comparable to the titanium implant. PMID:23876712

Eser, Atilim; Tonuk, Ergin; Akca, Kivanc; Dard, Michel M; Cehreli, Murat Cavit

2013-09-01

168

Bone quality and bone strength: benefits of the bone-forming approach  

PubMed Central

Summary The ability of bone to resist fracture depends on the intrinsic properties of the materials that comprise the bone matrix mineralization, the amount of bone (i.e. mass), and the spatial distribution of the bone mass (i.e. microarchitecture). Antiresorptive agents may prevent the decay of cancellous bone and cortical thinning, with no improvement of bone microstructure, leading to a partial correction of the principal bone quality defect in osteoporosis, the disruption of trabecular microarchitecture. Anabolic agents promote bone formation at both trabecular and endocortical surfaces, resulting in an increase of cancellous bone volume and cortical thickness. The improvement of cortical bone strength may be limited by an increase in cortical porosity. strontium ranelate improves trabecular network and cortical thickness that will contribute to anti-fracture efficacy at both vertebral and non-vertebral sites. The results of clinical and experimental studies are consistent with the mode of action of strontium involving dissociation between bone formation and resorption leading to a stimulation both trabecular and cortical bone formation without increasing cortical porosity. PMID:25002875

Iolascon, Giovanni; Frizzi, Laura; Di Pietro, Gioconda; Capaldo, Annarita; Luciano, Fabrizio; Gimigliano, Francesca

2014-01-01

169

Space flight and bone formation  

NASA Technical Reports Server (NTRS)

Major physiological changes which occur during spaceflight include bone loss, muscle atrophy, cardiovascular and immune response alterations. When trying to determine the reason why bone loss occurs during spaceflight, one must remember that all these other changes in physiology and metabolism may also have impact on the skeletal system. For bone, however, the role of normal weight bearing is a major concern and we have found no adequate substitute for weight bearing which can prevent bone loss. During the study of this problem, we have learned a great deal about bone physiology and increased our knowledge about how normal bone is formed and maintained. Presently, we do not have adequate ground based models which can mimic the tissue loss that occurs in spaceflight but this condition closely resembles the bone loss seen with osteoporosis. Although a normal bone structure will respond to application of mechanical force and weight bearing by forming new bone, a weakened osteoporotic bone may have a tendency to fracture. The study of the skeletal system during weightless conditions will eventually produce preventative measures and form a basis for protecting the crew during long term space flight. The added benefit from these studies will be methods to treat bone loss conditions which occur here on earth.

Doty, St B.

2004-01-01

170

Cancer to bone: a fatal attraction  

PubMed Central

When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and invasion, is central to the pathophysiology of bone metastases. Basic findings of tumour–bone interactions have uncovered numerous therapeutic opportunities that focus on the bone microenvironment to prevent and treat bone metastases. PMID:21593787

Weilbaecher, Katherine N.; Guise, Theresa A.; McCauley, Laurie K.

2013-01-01

171

[Bone tissue: rebuilding and inflammation].  

PubMed

In this review the author summarizes the knowledge related to structural elements of bone tissue. The process of bone reorganisation and knowledge about the special feature of bone metabolism in human are also discussed. It is noted that due to the reorganisation, there is a complete renewal of bone tissue in every 10 years, and this renewal lasts throughout the life. However, there are life periods when osteoclast activity is low, e.g. in childhood and the second decade of life when the gain of bone mass may be as much as 40% of the final bone mass. Overactivity of osteoclasts occurs at age 60 years in men and somewhat earlier in women. Reorganization of bone tissue is an elementary requirement for the physiological functions (locomotion, hemopoiesis, immune functions). The RANK-RANKL-osteoprotegerin axis plays an important role in the regulation of bone metabolism. Bone mass is dependent on osteocytes; osteoblasts are building up while osteoclasts are reabsorbing bone tissue. In this process transcription factors, hormone-like substances and a large number of cytokines are involved. In addition, the inflammatory process within the bone tissue as well as the defending, reparative inflammation and specific immune response are of great importance in bone reorganisation. This is particularly valid for ?2-macroglobulin and transforming growth factor, although the exact role in bone reorganization has not been fully explored. It can be concluded that the elements, which participate in bone reorganization and in defending inflammatory and specific immunological processes, are essentially identical. Therefore, the existence of an osteo-immunological complex system has been emerged. PMID:25261988

Jakab, Lajos

2014-10-01

172

Osteopontin Deficiency Increases Bone Fragility but Preserves Bone Mass  

PubMed Central

The ability of bone to resist catastrophic failure is critically dependent upon the material properties of bone matrix, a composite of hydroxyapatite, collagen type I, and noncollagenous proteins. These properties include elastic modulus, hardness, and fracture toughness. Like other aspects of bone quality, matrix material properties are biologically-defined and can be disrupted in skeletal disease. While mineral and collagen have been investigated in greater detail, the contribution of noncollagenous proteins such as osteopontin to bone matrix material properties remains unclear. Several roles have been ascribed to osteopontin in bone, many of which have the potential to impact material properties. To elucidate the role of osteopontin in bone quality, we evaluated the structure, composition, and material properties of bone from osteopontin-deficient mice and wild-type littermates at several length scales. Most importantly, the results show that osteopontin deficiency causes a 30% decrease in fracture toughness, suggesting an important role for OPN in preventing crack propagation. This significant decline in fracture toughness is independent of changes in whole bone mass, structure, or matrix porosity. Using nanoindentation and quantitative backscattered electron imaging to evaluate osteopontin-deficient bone matrix at the micrometer level, we observed a significant reduction in elastic modulus and increased variability in calcium concentration. Matrix heterogeneity was also apparent at the ultrastructural level. In conclusion, we find that osteopontin is essential for the fracture toughness of bone, and reduced toughness in osteopontin-deficient bone may be related to the increased matrix heterogeneity observed at the micro-scale. By exploring the effects of osteopontin-deficiency on bone matrix material properties, composition and organization, this study suggests that reduced fracture toughness is one mechanism by which loss of noncollagenous proteins contribute to bone fragility. PMID:20171304

Thurner, Philipp J.; Chen, Carol G.; Ionova-Martin, Sophi; Sun, Luling; Harman, Adam; Porter, Alexandra; Ager, Joel W.; Ritchie, Robert O.; Alliston, Tamara

2010-01-01

173

Osteopontin deficiency increases bone fragility but preserves bone mass.  

PubMed

The ability of bone to resist catastrophic failure is critically dependent upon the material properties of bone matrix, a composite of hydroxyapatite, collagen type I, and noncollagenous proteins. These properties include elastic modulus, hardness, and fracture toughness. Like other aspects of bone quality, matrix material properties are biologically-defined and can be disrupted in skeletal disease. While mineral and collagen have been investigated in greater detail, the contribution of noncollagenous proteins such as osteopontin to bone matrix material properties remains unclear. Several roles have been ascribed to osteopontin in bone, many of which have the potential to impact material properties. To elucidate the role of osteopontin in bone quality, we evaluated the structure, composition, and material properties of bone from osteopontin-deficient mice and wild-type littermates at several length scales. Most importantly, the results show that osteopontin deficiency causes a 30% decrease in fracture toughness, suggesting an important role for OPN in preventing crack propagation. This significant decline in fracture toughness is independent of changes in whole bone mass, structure, or matrix porosity. Using nanoindentation and quantitative backscattered electron imaging to evaluate osteopontin-deficient bone matrix at the micrometer level, we observed a significant reduction in elastic modulus and increased variability in calcium concentration. Matrix heterogeneity was also apparent at the ultrastructural level. In conclusion, we find that osteopontin is essential for the fracture toughness of bone, and reduced toughness in osteopontin-deficient bone may be related to the increased matrix heterogeneity observed at the micro-scale. By exploring the effects of osteopontin deficiency on bone matrix material properties, composition and organization, this study suggests that reduced fracture toughness is one mechanism by which loss of noncollagenous proteins contribute to bone fragility. PMID:20171304

Thurner, Philipp J; Chen, Carol G; Ionova-Martin, Sophi; Sun, Luling; Harman, Adam; Porter, Alexandra; Ager, Joel W; Ritchie, Robert O; Alliston, Tamara

2010-06-01

174

Vitamin D: beyond bone  

PubMed Central

In recent years, vitamin D has been received increased attention due to the resurgence of vitamin D deficiency and rickets in developed countries and the identification of extraskeletal effects of vitamin D, suggesting unexpected benefits of vitamin D in health and disease, beyond bone health. The possibility of extraskeletal effects of vitamin D was first noted with the discovery of the vitamin D receptor (VDR) in tissues and cells that are not involved in maintaining mineral homeostasis and bone health, including skin, placenta, pancreas, breast, prostate and colon cancer cells, and activated T cells. However, the biological significance of the expression of the VDR in different tissues is not fully understood, and the role of vitamin D in extraskeletal health has been a matter of debate. This report summarizes recent research on the roles for vitamin D in cancer, immunity and autoimmune diseases, cardiovascular and respiratory health, pregnancy, obesity, erythropoiesis, diabetes, muscle function, and aging. PMID:23682710

Christakos, Sylvia; Hewison, Martin; Gardner, David G; Wagner, Carol L; Sergeev, Igor N; Rutten, Erica; Pittas, Anastassios G; Boland, Ricardo; Ferrucci, Luigi; Bikle, Daniel D

2013-01-01

175

Vitamin D: beyond bone.  

PubMed

In recent years, vitamin D has been received increased attention due to the resurgence of vitamin D deficiency and rickets in developed countries and the identification of extraskeletal effects of vitamin D, suggesting unexpected benefits of vitamin D in health and disease, beyond bone health. The possibility of extraskeletal effects of vitamin D was first noted with the discovery of the vitamin D receptor (VDR) in tissues and cells that are not involved in maintaining mineral homeostasis and bone health, including skin, placenta, pancreas, breast, prostate and colon cancer cells, and activated T cells. However, the biological significance of the expression of the VDR in different tissues is not fully understood, and the role of vitamin D in extraskeletal health has been a matter of debate. This report summarizes recent research on the roles for vitamin D in cancer, immunity and autoimmune diseases, cardiovascular and respiratory health, pregnancy, obesity, erythropoiesis, diabetes, muscle function, and aging. PMID:23682710

Christakos, Sylvia; Hewison, Martin; Gardner, David G; Wagner, Carol L; Sergeev, Igor N; Rutten, Erica; Pittas, Anastassios G; Boland, Ricardo; Ferrucci, Luigi; Bikle, Daniel D

2013-05-01

176

Bone Metabolism on ISS Missions  

NASA Technical Reports Server (NTRS)

Spaceflight-induced bone loss is associated with increased bone resorption (1, 2), and either unchanged or decreased rates of bone formation. Resistive exercise had been proposed as a countermeasure, and data from bed rest supported this concept (3). An interim resistive exercise device (iRED) was flown for early ISS crews. Unfortunately, the iRED provided no greater bone protection than on missions where only aerobic and muscular endurance exercises were available (4, 5). In 2008, the Advanced Resistive Exercise Device (ARED), a more robust device with much greater resistance capability, (6, 7) was launched to the ISS. Astronauts who had access to ARED, coupled with adequate energy intake and vitamin D status, returned from ISS missions with bone mineral densities virtually unchanged from preflight (7). Bone biochemical markers showed that while the resistive exercise and adequate energy consumption did not mitigate the increased bone resorption, bone formation was increased (7, 8). The typical drop in circulating parathyroid hormone did not occur in ARED crewmembers. In 2014, an updated look at the densitometry data was published. This study confirmed the initial findings with a much larger set of data. In 42 astronauts (33 male, 9 female), the bone mineral density response to flight was the same for men and women (9), and those with access to the ARED did not have the typical decrease in bone mineral density that was observed in early ISS crewmembers with access to the iRED (Figure 1) (7). Biochemical markers of bone formation and resorption responded similarly in men and women. These data are encouraging, and represent the first in-flight evidence in the history of human space flight that diet and exercise can maintain bone mineral density on long-duration missions. However, the maintenance of bone mineral density through bone remodeling, that is, increases in both resorption and formation, may yield a bone with strength characteristics different from those that existed before space flight. Studies to assess bone strength after flight are underway at NASA, to better understand the results of bone remodeling. Studies are also underway to evaluate optimized exercise protocols and nutritional countermeasures. Regardless, there is clear evidence of progress being made to protect bone during spaceflight.

Smith, S. M.; Heer, M. A.; Shackelford, L. C.; Zwart, S. R.

2014-01-01

177

Shang Oracle Bones  

NASA Astrophysics Data System (ADS)

Astronomical observations first appear in China's archaeological record on turtle plastrons and ox scapulae from the reigns of the last few kings of the Shang Dynasty (1250-1046 BCE). A variety of meteorological and astronomical phenomena were divined about and recorded by scribes in formulaic language that is recognizably archaic Chinese. The oracle bone inscriptions record sacrifices to celestial bodies and the proper ritual response to anomalous phenomena like eclipses.

Pankenier, David W.

178

Biomechanics of Bone  

Microsoft Academic Search

\\u000a The ability to bear loads is a critical function of the skeleton, in addition to its metabolic and physiological roles. Load-bearing\\u000a ability depends on both the applied loads and the structural properties of the loaded bone. When the loads exceed the structural\\u000a properties, fracture will occur. Because the nature of the applied loads can be difficult to predict, the greatest

Jacqueline H. Cole; Marjolein C. H. Meulen

179

Exploring Bone Mineral Density  

NSDL National Science Digital Library

In this activity, students will explore two given websites to gather information on Bone Mineral Density and how it is measured. They will also learn about X-rays in general, how they work and their different uses, along with other imaging modalities. They will answer guiding questions as they explore the websites and take a short quiz after to test the knowledge they gained while reading the articles.

Vu Bioengineering Ret Program

180

Treatment of Bone Tumors  

PubMed Central

Synopsis In this article, the authors summarize the state of the art and future potential in the management of Osteosarcoma, Ewing’s sarcoma, and Chondrosarcoma. They cover systemic therapy, surgical therapy, and radiotherapy, along with targeted therapies to inhibit signal transduction pathways. They discuss staging and the role of imaging evaluation to provide an overview of bone tumor treatment. Images presenting pathologic-radiologic correlations are included. PMID:22328909

Rajani, Rajiv; Gibbs, C. Parker

2012-01-01

181

Zoledronate reduces unwanted bone resorption in intercalary bone allografts  

PubMed Central

Bone allografts are often hampered by graft incorporation and poor host bone formation. Bisphosphonates, synthetic pyrophosphate analogs, have shown promise in inhibiting bone resorption in human and animal trials. Some in vitro studies have suggested that high dose bisphosphonate may also inhibit bone formation, leading to our hypothesis that an ideal dose of bisphosphonate in allografts could protect allografts from resorption. We transplanted intercalary allografts in to the segmental defect of the rat femurs after soaking each allograft in zoledronate solution (30 µM) and then analysed bone density of the allografts six to 12 weeks after transplantation. At six and 12 weeks, the bone mineral density was higher in the experimental group compared with the control group. Qualitative radiographic and histological analysis also revealed more allograft resorption in the control group than in the zoledronate-treated group. Our data indicate that pharmacological modification of intercalary allografts with zoledronate solution can decrease osteoclast-mediated allograft resorption. PMID:19343345

Seo, Sung W.; Cho, Samuel K.; Storer, Steven K.

2009-01-01

182

Bone lead in dialysis patients.  

PubMed

We measured lead and calcium in multiple bone biopsies from 11 cadavers without known excessive past exposure to lead. Paired iliac crest, transiliac and tibial bone biopsies from these cadavers indicated that in bone biopsy specimens the lead/calcium ratio is more reproducible than the absolute lead concentration. There were no significant differences between the lead/calcium ratios from the iliac crest, transiliac, or tibial specimens. Transiliac bone biopsies from 35 patients (13 patients showing symptoms of slight or moderate degree of renal failure, medical history of gout and/or arterial hypertension and 22 lead workers with chelatable lead in excess of 1000 micrograms) indicated that the lead and the lead/calcium ratio in bone biopsies reflect body lead stores as estimated by the EDT A test (r = 0.87 and 0.83, respectively). Chemical and histological studies of transiliac biopsies previously obtained from 153 dialysis patients (from 8 dialysis centers from Belgium, France and Germany) for studies of aluminum-induced bone disease showed that chronic renal failure and dialysis do not cause accumulation of lead in bone and elevated bone lead does not appear to alter trabecular bone histomorphometry. We found that in 5% of the hemodialysis population studied, bone lead concentrations approximated levels found in active lead workers. PMID:3129611

Van de Vyver, F L; D'Haese, P C; Visser, W J; Elseviers, M M; Knippenberg, L J; Lamberts, L V; Wedeen, R P; De Broe, M E

1988-02-01

183

Bone disease in primary hyperparathyroidism  

PubMed Central

Bone disease in severe primary hyperparathyroidism (PHPT) is described classically as osteitis fibrosa cystica (OFC). Bone pain, skeletal deformities and pathological fractures are features of OFC. Bone mineral density is usually extremely low in OFC, but it is reversible after surgical cure. The signs and symptoms of severe bone disease include bone pain, pathologic fractures, proximal muscle weakness with hyperreflexia. Bone involvement is typically characterized as salt-and-pepper appearance in the skull, bone erosions and bone resorption of the phalanges, brown tumors and cysts. In the radiography, diffuse demineralization is observed, along with pathological fractures, particularly in the long bones of the extremities. In severe, symptomatic PHPT, marked elevation of the serum calcium and PTH concentrations are seen and renal involvement is manifested by nephrolithiasis and nephrocalcinosis. A new technology, recently approved for clinical use in the United States and Europe, is likely to become more widely available because it is an adaptation of the lumbar spine DXA image. Trabecular bone score (TBS) is a gray-level textural analysis that provides an indirect index of trabecular microarchitecture. Newer technologies, such as high-resolution peripheral quantitative computed tomography (HR-pQCT), have provided further understanding of the microstructural skeletal features in PHPT. PMID:25166047

Bandeira, Francisco; Cusano, Natalie E.; Silva, Barbara C.; Cassibba, Sara; Almeida, Clarissa Beatriz; Machado, Vanessa Caroline Costa; Bilezikian, John P.

2015-01-01

184

Androgens and Bone  

PubMed Central

Testosterone is the major gonadal sex steroid produced by the testes in men. Testosterone is also produced in smaller amounts by the ovaries in women. The adrenal glands produce the weaker androgens dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione. These androgens collectively affect skeletal homeostasis throughout life in both men and women, particularly at puberty and during adult life. Because testosterone can be metabolized to estradiol by the aromatase enzyme, there has been controversy as to which gonadal sex steroid has the greater skeletal effect. The current evidence suggests that estradiol plays a greater role in maintenance of skeletal health than testosterone, but that androgens also have direct beneficial effects on bone. Supraphysiological levels of testosterone likely have similar effects on bone as lower levels via direct interaction with androgen receptors, as well as effects mediated by estrogen receptors after aromatization to estradiol. Whether high doses of synthetic, non-aromatizable androgens may, in fact, be detrimental to bone due to suppression of endogenous testosterone (and estrogen) levels is a potential concern that warrants further study. PMID:18992761

Clarke, Bart L.; Khosla, Sundeep

2009-01-01

185

Battling Brittle Bones  

NASA Technical Reports Server (NTRS)

The accuDEXA(R) Bone Mineral Density Assessment System, manufactured by Schick Technologies, Inc., utilizes "camera on a chip" sensor technology invented and developed by NASA's Jet Propulsion Laboratory. Schick's accuDEXA system offers several advantages over traditional osteoporosis tests, which assess bone density loss in the hip and spine, and require specialized personnel to conduct. With accuDEXA, physicians can test the entire body's bone density at a peripheral site, such as the finger, without applying gels or having patients remove garments. Results are achieved in 30 seconds and printed out in less than a minute, compared to the estimated exam time of 15 minutes for hip and spine density analyses. Schick has also applied the CMOS APS technology to a new software product that performs dental radiography using up to 90 percent less radiation exposure than conventional X-rays. Called Computed Dental Radiography(R), the new digital imaging product utilizes an electronic sensor in place of X-ray film to generate sharp and clear images that appear on a computer screen within 3 seconds, and can be enlarged and enhanced to identify problems.

2002-01-01

186

Bone quality: the material and structural basis of bone strength  

Microsoft Academic Search

The material composition and structural design of bone determine its strength. Structure determines loads that can be tolerated\\u000a but loads also determine structure. Bone modifies its material composition and structure to accommodate loads by adaptive\\u000a modeling and remodeling. Adaptation is successful during growth but not aging because accumulating insults, including a reduction\\u000a in the volume of bone formed in the

Ego Seeman

2008-01-01

187

Microgravity and bone cell mechanosensitivity  

NASA Astrophysics Data System (ADS)

The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms involved remained poorly understood. Bone not only develops as a structure designed specifically for mechanical tasks, but it can adapt during life toward more efficient mechanical performance. Mechanical adaptation of bone is a cellular process and needs a biological system that senses the mechanical loading. The loading information must then be communicated to the effector cells that form new bone or destroy old bone. The in vivo operating cell stress derived from bone loading is likely the flow of interstitial fluid along the surface of osteocytes and lining cells. The response of bone cells in culture to fluid flow includes prostaglandin (PG) synthesis and expression of prostaglandin G/H synthase inducible cyclooxygenase (COX-2). Cultured bone cells also rapidly produce nitric oxide (NO) in response to fluid flow as a result of activation of endothelial nitric oxide synthase (ecNOS), which enzyme also mediates the adaptive response of bone tissue to mechanical loading. Earlier studies have shown that the disruption of the actin-cytoskeleton abolishes the response to stress, suggesting that the cytoskeleton is involved in cellular mechanotransduction. Microgravity, or better near weightlessness, is associated with the loss of bone in astronauts, and has catabolic effects on mineral metabolism in bone organ cultures. This might be explained as resulting from an exceptional form of disuse under near weightlessness conditions. However, under near weightlessness conditions the assembly of cytoskeletal elements may be altered since it has been shown that the direction of the gravity vector determines microtubular pattern formation in vivo. We found earlier that the transduction of mechanical signals in bone cells also involves the cytoskeleton and is related to PGEZ production. Therefore it is possible that the mechanosensitivity of bone cells is altered under near weightlessness conditions, and that this abnormal mechanosensation contributes to disturbed bone metabolism observed in astronauts. In our current project for the International Space Station, we wish to test this hypothesis experimentally using an in vitro model. The specific aim of our research project is to test whether near weightlessness decreases the sensitivity of bone cells for mechanical stress through a decrease in early signaling molecules (NO, PGs) that are involved in the mechanical loading-induced osteogenic response. Bone cells are cultured with or without gravity prior to and during mechanical loading, using our modified in vitro oscillating fluid flow apparatus. In this "FlowSpace" project we are developing a cell culture module that is used to provide further insight in the mechanism of mechanotransduction in bone.

Klein-Nulend, J.; Bacabac, R. G.; Veldhuijzen, J. P.; Van Loon, J. J. W. A.

2003-10-01

188

Electromechanical Properties of Bone Tissue.  

NASA Astrophysics Data System (ADS)

Discrepancies between calculated and empirical properties of bone are thought to be due to a general lack of consideration for the extent and manner(s) with which bone components interact at the molecular level. For a bone component in physiological fluid or whenever two phases are in contact, there is a region between the bulk phases called the electrical double layer which is marked by a separation of electric charges. For the purpose of studying electrical double layer interactions, the method of particle microelectrophoresis was used to characterize bone and its major constituents on the basis of the net charge they bear when suspended in ionic media of physiological relevance. With the data presented as pH versus zeta (zeta ) potential, the figures reveal an isoelectric point (IEP) for bone mineral near pH 8.6, whereas intact and EDTA demineralized bone tissue both exhibit IEPs near pH 5.1. While these data demonstrate the potential for a significant degree of coulombic interaction between the bone mineral and organic constituent double layers, it was also observed that use of inorganic phosphate buffers, as a specific marker for bone mineral, resulted in (1) an immediate reversal, from positive to negative, of the bone mineral zeta potential (2) rendered the zeta potential of intact bone more negative in a manner linearly dependent on both time and temperature and (3) had no affect on demineralized bone (P < 0.01). In agreement with that shown in model protein-hydroxyapatite systems, it is suggested here that inorganic phosphate ions in solution compete with organic acid groups (e.g. carboxyl and phosphate of collagen, sialoprotein, ...) for positively charged sites on the bone mineral surface and effectively uncouple the bone mineral and organic phase double layers. Mechanically, this uncoupling is manifested as a loss of tissue rigidity when monitoring the midspan deflection of bone beams subject to constant load for a 3 day period. While it is thus demonstrated that the major inorganic and organic phases of bone are electromechanically coupled, a thermodynamic consideration of the data suggests that the nature of the bond is to preserve mineral and organic phase electroneutralities by participating in electrical double layer interactions. The results are discussed in terms of bone mechanical modeling, electrokinetic properties, aging, tissue-implant compatibility and the etiologies of bone pathologic conditions.

Regimbal, Raymond L.

189

Roentgenologic aspects of bone islands.  

PubMed

A review of radiographs of 143 Adult Health Study and 46 non-sample subjects made over a period of 23 years established sites, sizes, ages at detection, and prevalence of 209 bone islands in 189 subjects. Except for 18 new bone islands, all appeared during the period of observation. Twenty-six of them changed: of these, 21 enlarged, 4 became smaller, and 1 disappeared. There was no association with atomic bomb radiation dose. Bone islands were more frequent in the pelvis and femora but often occurred in the ribs. Five bone islands in adolescents enlarged proportionally to bone growth, suggesting that they often participate metabolically in the normal osseous system. Bone islands must be differentiated from osteoblastic metastases. PMID:870936

Onitsuka, H

1977-06-01

190

ALLOGRAFT VERSUS AUTOGRAFT BONE IN SCOLIOSIS SURGERY  

Microsoft Academic Search

The results of a study of the use of autograft versus allograft bone in the surgery of idiopathic adolescent scoliosis are presented. Two groups of patients, matched for age, sex, level and angle of curve, received bone grafts, 20 patients having autogenous bone from the ifiac crest and the other 20 having donor bone from a bone bank. Both groups

C. A. F. DODD; C. M. FERGUSSON; L. FREEDMAN; G. R. HOUGHTON; D. THOMAS

191

Stress fractures and bone pain  

SciTech Connect

Stress fractures result from an unusual repetitive physical activity causing absorption of bone in excess of repair and bone formation. This leads to the weakening of the bone and subsequently to a fracture. It is a benign condition that if recognized in time does not need any treatment besides rest. However, if diagnosis is not made and physical activity continues it may result in severe injury to the bone and a frank fracture may result. Pain is the typical clinical feature and bone scintigraphy, being more sensitive than radiography, is done to establish early diagnosis. The presence of asymptomatic sites of abnormal bone uptake typical of stress fracture in which pain appeared only about 2 weeks after scintigraphy, drew the authors' attention to the question of how close is the relationship between stress fractures and bone pain. Sixty-four military recruits diagnosed as suffering from stress fracture were investigated in order to correlate sites with abnormal uptake of Tc-99m MDP on bone scintigraphy with sites of local pain. In 37 (58%) subjects multiple sites of abnormal uptake were recognised. Of 123 sites of abnormal uptake, 31 (25%) were asymptomatic. In three patients bone pain appeared at the site of the abnormal uptake two weeks after scintigraphy. Bone scintigraphy appears to be more sensitive than bone pain in the diagnosis of stress fractures. The osteoblastic activity which manifests itself by abnormal uptake appears in some cases earlier than the pain caused by the fracture. Present findings may suggest that under certain circumstances, in a population prone to stress fracture, bone scan should be considered as a screening method.

Groshar, D.; Even-Sapir, E.; Lam, M.; Israel, O.; Front, D.

1984-01-01

192

Bone Health in The Balance  

NSDL National Science Digital Library

Our bones are continuously being remodeled through repeated cycles of destruction and rebuilding. By some estimates, this remodeling process is so extensive that it completely regenerates the adult skeleton every 10 years. Remodeling most likely serves a repair function, especially in bones subjected to mechanical stress. This article introduces a special issue of Science on recent advances in our understanding of the cell and molecular biology of bone remodeling and how these advances are being applied to the development of new therapeutics.

Paula Kiberstis (AAAS;); Orla Smith (AAAS;); Colin Norman (AAAS;)

2000-09-01

193

Imaging of temporal bone trauma.  

PubMed

Temporal bone trauma is commonly seen in patients with craniofacial injury and can be detected using multidetector computed tomography. A thorough understanding of the different types of temporal bone fracture patterns is needed to accurately describe the trajectory of injury as well as anticipated complications. Fractures should be described based on direction, segment of temporal bone involved, as well as involvement of the otic capsule. More importantly, the radiologist plays an integral role in identifying complications of temporal bone injury, which often have significant clinical implications. PMID:25086807

Kennedy, Tabassum A; Avey, Gregory D; Gentry, Lindell R

2014-08-01

194

Inflammatory studies on bone cement.  

E-print Network

?? Simvastatin, a cholesterol lowering drug, has the capacity to stimulate bone formation along with having anti-inflammatory effects. Incorporating simvastatin to the calcium phosphate cement… (more)

Modugu, Asha

2012-01-01

195

Postradiation atrophy of mature bone  

SciTech Connect

The growing number of oncological patients subjected to radiotherapy require the diagnostic radiologist to be aware of expected bone changes following irradiation and the differentiation of this entity from metastasis. The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographic evidence of atrophy, localized osteopenia, is late in appearing, mainly because of the relative insensitivity of radiographs in detecing demineralization. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. In vivo midrodensitometric analysis and radionuclide bone and bone marrow scans can reveal early changes following irradiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.

Ergun, H.; Howland, W.J.

1980-01-01

196

Microgravity and Bone Cell Mechanosensitivity  

NASA Astrophysics Data System (ADS)

The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms involved remained poorly understood. Bone not only develops as a structure designed specifically for mechanical tasks, but it can adapt during life toward more efficient mechanical performance. Mechanical adaptation of bone is a cellular process and needs a biological system that senses the mechanical loading. The loading information must then be communicated to the effector cells that form new bone or destroy old bone.The in vivo operating cell stress derived from bone loading is likely flow of interstitial fluid along the surface of osteocytes and lining cells. The response of bone cells in culture to fluid flow includes prostaglandin (PG) synthesis and expression of prostaglandin G/H synthase inducible cyclooxygenase (COX-2). Cultured bone cells also rapidly produce nitric oxide (NO) in response to fluid flow as a result of activation of endothelial nitric oxide synthase (ecNOS), which enzyme also mediates the adaptive response of bone tissue to mechanical loading. Disruption of the actin-cytoskeleton abolishes the response to stress, suggesting that the cytoskeleton is involved in cellular mechanotransduction.Microgravity, or better near weightlessness, has catabolic effects on the skeleton of astronauts, and on mineral metabolism in bone organ cultures. This might be explained as resulting from an exceptional form of disuse under near weightlessness conditions. However, under near weightlessness conditions the assembly of cytoskeletal elements may be altered since it has been shown that the direction of the gravity vector determines microtubular pattern formation in vivo. We found that the transduction of mechanical signals in bone cells also involves the cytoskeleton and is related to PGE2 production. Therefore it is possible that the mechanosensitivity of bone cells is altered under near weightlessness conditions, and that this abnormal mechanosensation contributes to disturbed bone metabolism observed in astronauts.In our current project for the International Space Station, we wish to test this hypothesis experimentally using an in vitro model. The specific aim of our research project is to test whether near weightlessness decreases the sensitivity of bone cells for mechanical stress through a decrease in early signaling molecules (NO, PGs) that are involved in the mechanical loading-induced osteogenic response. Bone cells are cultured with or without gravity prior to and during mechanical loading, using our modified in vitro oscillating fluid flow apparatus. In this "FlowSpace" project we are developing a cell culture module that is used to provide further insight in the mechanism of mechanotransduction in bone.

Klein-Nulend, J.; Bacabac, R.; Veldhuijzen, J.; van Loon, J.

197

Bone grafting in shoulder arthroplasty.  

PubMed

Shoulder arthroplasty is one of the fastest-growing fields in orthopedic surgery. Deficiency of the glenoid or humeral bone stock is a major challenge that can result from degenerative arthritis, component loosening or extraction, fracture, or malignancy. Approximately 15% of primary reconstructions will require bone grafting, and the rate is higher for revisions. The authors present a systematic review of the current literature focused on the indications for and results of bone grafting techniques. This provides the practicing surgeon with a set of strategies to address bone loss in the primary and revision settings, whether using an anatomic or reverse design. PMID:23127445

Riboh, Jonathan C; Garrigues, Grant E

2012-11-01

198

Elastic intramedullary nailing and DBM-Bone marrow injection for the treatment of simple bone cysts  

Microsoft Academic Search

BACKGROUND: Simple or unicameral bone cysts are common benign fluid-filled lesions usually located at the long bones of children before skeletal maturity. METHODS: We performed demineralized bone matrix and iliac crest bone marrow injection combined with elastic intramedullary nailing for the treatment of simple bone cysts in long bones of 9 children with a mean age of 12.6 years (range,

Anastasios D Kanellopoulos; Andreas F Mavrogenis; Panayiotis J Papagelopoulos; Panayotis N Soucacos

2007-01-01

199

Autologous bone graft versus demineralized bone matrix in internal fixation of ununited long bones  

Microsoft Academic Search

BACKGROUND: Non-unions are severe complications in orthopaedic trauma care and occur in 10% of all fractures. The golden standard for the treatment of ununited fractures includes open reduction and internal fixation (ORIF) as well as augmentation with autologous-bone-grafting. However, there is morbidity associated with the bone-graft donor site and some patients offer limited quantity or quality of autologous-bone graft material.

Oliver Pieske; Alexandra Wittmann; Johannes Zaspel; Thomas Löffler; Bianka Rubenbauer; Heiko Trentzsch; Stefan Piltz

2009-01-01

200

Bones in Balance  

NSDL National Science Digital Library

Thirty-first monthly installment of our "What A Year!" website project, introducing life science breakthroughs to middle and high school students and their teachers. Our bones change throughout our lives, building and increasing in density to our 30's and then decreasing in density thereafter. People who don't get exercise, such as those who must remain in bed for long periods of time, can suffer early osteoporosis. But why don't bears, who hibernate for half a year, experience the same problem?

2009-10-05

201

Rhabdomyosarcoma infiltrating bone marrow.  

PubMed

We present a case of 26-year-old male, previously diagnosed as rhabdomyosarcoma (RMS) of perineal region. The peripheral smear showed a leukoerythroblastic picture with an occasional atypical cell. The bone marrow aspirate and biopsy showed monotonous sheets of malignant cells. On immunohistochemistry the tumor cells were strongly positive for desmin and negative for CD34 and CD117. This case illustrates the morphology and IHC findings in a case of RMS. Immunostains like CD34 and CD117 should be included to rule out a possibility of acute leukemia. PMID:25348638

Chauhan, Kriti; Jain, Monica; Shukla, Pragya; Grover, R K

2015-01-01

202

Paget’s disease of the bone  

MedlinePLUS

... people with Paget's disease, there is an abnormal breakdown of bone tissue in specific areas. This is, ... scan Bone x-ray Elevated markers of bone breakdown (for instance, N-telopeptide) This disease may also ...

203

Exercise Brings Bone Benefits that Last  

MedlinePLUS

... External link, please review our exit disclaimer . Subscribe Exercise Brings Bone Benefits that Last Building bone as ... lose bone. Studies of animals have shown that exercise during periods of rapid growth can lead to ...

204

Bone Density Testing (Beyond the Basics)  

MedlinePLUS

... weight it was holding. Graphic 53181 Version 6.0 Definitions of normal bone density, osteopenia, and osteoporosis ... Normal bone density Bone density that is between 0 and 1 standard deviation below the mean is ...

205

Bone disease in primary hyperparathyrodism  

PubMed Central

Nowadays, primary hyperparathyroidism (PHPT) is mostly a mild disease. Overt skeletal manifestations are rare but decreased bone mineral density (BMD) can still be demonstrated. Even in mild cases, excess parathyroid hormone (PTH) increases bone turnover leading to bone loss particularly at cortical sites. Conversely, a relative preservation of cancellous bone has been shown by histomorphometric analyses and advanced imaging techniques. An increased fracture rate has been demonstrated in untreated patients with PHPT at peripheral sites and in the spine. Parathyroidectomy (PTx) is the definitive cure for PHPT. With the restoration of normal PTH, bone resorption is quickly tapered down, while bone formation proceeds at the level of bone multicellular units, which were activated prior to PTx. The rapid refilling of the enlarged remodeling space and the subsequent matrix mineralization will result in an increase in BMD at sites rich in trabecular bone, such as lumbar spine and hip, which mainly occurs during the first 6–12 months after PTx. Cortical bone is less responsive to PTX because of the low rate of bone turnover, but sensible increases in BMD at the distal third of the radius can be observed in the long term. PTx seems to decrease the risk of fractures but more data are needed before a definitive conclusion on this important matter can be reached. Treatment with bisphosphonates can be considered for patients with low BMD who do not undergo PTx. Two-year treatment with alendronate has been shown to decrease bone turnover markers and increase BMD at the lumbar spine and hip, but not at the distal radius. Cinacalcet stably decreased serum calcium levels across a broad range of PHPT severity, but no change in BMD occurred in patients treated for up to 5.5 years. PMID:23024712

Cianferotti, Luisella; Cetani, Filomena

2012-01-01

206

Modulation of Bone Resorption by Phosphorylation State of Bone Sialoprotein  

PubMed Central

We have determined transmembrane protein tyrosine phosphorylation (outside-in signaling) in cultured osteoclasts and macrophages in response to added native purified BSP (nBSP) and its dephosphorylated form (dBSP). There were selective/differential and potent inhibitory effects by dBSP and minimal effect by nBSP on intracellular tyrosine phosphorylation in macrophages and osteoclasts. Further studies on the down-stream gene expression effects led to identification of a large number of differentially expressed genes in response to nBSP relative to dBSP in both macrophages and osteoclasts. These studies were extended to bone resorption model using live mouse neonatal calvarial bone organ cultures stimulated by parathyroid hormone (PTH) to undergo bone resorption. Inclusion of nBSP in such cultures showed no effect on type I collagen telopeptide fragment release, hence overall bone resorption, whereas addition of dBSP abolished the PTH-induced bone resorption. The inhibition of bone resorption by dBSP was shown to be unique since in complementary experiments use of integrin receptor binding ligand, GRGDS peptide, offered only partial reduction on overall bone resorption. Quantitative RANKL analysis indicated that mechanistically the PTH-induced bone resorption was inhibited by dBSP via down-regulation of the osteoblastic RANKL production. This conclusion was supported by the RANKL analysis in cultured MC3T3-E1 osteoblast cells. Overall, these studies provided direct evidence for the involvement of covalently-bound phosphates on BSP in receptor mediated ‘outside-in’ signaling via transmembrane tyrosine phosphorylation with concurrent effects on down-stream gene expressions. The use of a live bone organ culture system augmented these results with further evidence that links the observed in vivo variable state of phosphorylation with bone remodeling. PMID:19518132

Curtin, Paul; McHugh, Kevin P.; Zhou, Hia-Yan; Flückiger, Rudolf; Goldhaber, Paul; Oppenheim, Frank G.; Salih, Erdjan

2009-01-01

207

Bone growth around dental implants.  

PubMed

For the complete understanding of stimulation of bone growth around dental implants, a thorough knowledge is necessary regarding the reaction of bone to trauma and to a variety of implant materials. The atraumatic preparation of the bony implant bed serves to create the most favorable situation for the formation of bone around any implant material. Some implant materials are more likely to result in soft tissue encapsulation despite the most careful handling of bone; others result in different amounts of implant-bone contact zones. From the character and the amount of bone formation around different implants, it can be concluded whether the used materials are biocompatible. Titanium-surfaced implants may not demonstrate the biocompatibility that is seen with hydroxyapatite-coated implants. However, the results seen with hydroxyapatite-coated implants have to be viewed critically because the biointegrity of these coatings has not been demonstrated until now. On the other hand, titanium-surfaced implants have success rates for as long as 25 years and enable the implantologist to rely on a well-accepted implant material. The use of guided tissue regeneration and the sinus augmentation technique appear to enable the implantologist to stimulate bone formation around dental implants. These techniques may extend the limits for the successful placement of dental implants into bone-deficient sites. PMID:1879579

Weinlaender, M

1991-07-01

208

Adaptation Models of Anisotropic Bone  

Microsoft Academic Search

A theoretical model and numerical methods were developed for testing different bone internal remodelling stimuli. The keystone of the study was the formulation of a stimulus based on the mechanical invariants of the stress tensor, which look into account bone non-homogeneity and anisotropy. A non-site specific remodelling rate equation was then used for the apparent density whereas anisotropy was fixed

A. TERRIER; R. L. RAKOTOMANANA; A. N. RAMANIRAKA; P. F. LEYVRAZ

1997-01-01

209

Bone tissue engineering in osteoporosis.  

PubMed

Osteoporosis is a polygenetic, environmentally modifiable disease, which precipitates into fragility fractures of vertebrae, hip and radius and also confers a high risk of fractures in accidents and trauma. Aging and the genetic molecular background of osteoporosis cause delayed healing and impair regeneration. The worldwide burden of disease is huge and steadily increasing while the average life expectancy is also on the rise. The clinical need for bone regeneration applications, systemic or in situ guided bone regeneration and bone tissue engineering, will increase and become a challenge for health care systems. Apart from in situ guided tissue regeneration classical ex vivo tissue engineering of bone has not yet reached the level of routine clinical application although a wealth of scaffolds and growth factors has been developed. Engineering of complex bone constructs in vitro requires scaffolds, growth and differentiation factors, precursor cells for angiogenesis and osteogenesis and suitable bioreactors in various combinations. The development of applications for ex vivo tissue engineering of bone faces technical challenges concerning rapid vascularization for the survival of constructs in vivo. Recent new ideas and developments in the fields of bone biology, materials science and bioreactor technology will enable us to develop standard operating procedures for ex vivo tissue engineering of bone in the near future. Once prototyped such applications will rapidly be tailored for compromised conditions like vitamin D and sex hormone deficiencies, cellular deficits and high production of regeneration inhibitors, as they are prevalent in osteoporosis and in higher age. PMID:23562167

Jakob, Franz; Ebert, Regina; Ignatius, Anita; Matsushita, Takashi; Watanabe, Yoshinobu; Groll, Juergen; Walles, Heike

2013-06-01

210

Space Radiation and Bone Loss  

PubMed Central

Exposure to ionizing radiation may negatively impact skeletal integrity during extended spaceflight missions to the moon, Mars, or near-Earth asteroids. However, our understanding of the effects of radiation on bone is limited when compared to the effects of weightlessness. In addition to microgravity, astronauts will be exposed to space radiation from solar and cosmic sources. Historically, radiation exposure has been shown to damage both osteoblast precursors and local vasculature within the irradiated volume. The resulting suppression of bone formation and a general state of low bone-turnover is thought to be the primary contributor to bone loss and eventual fracture. Recent investigations using mouse models have identified a rapid, but transient, increase in osteoclast activity immediately after irradiation with both spaceflight and clinically-relevant radiation qualities and doses. Together with a chronic suppression of bone formation after radiation exposure, this acute skeletal damage may contribute to long-term deterioration of bone quality, potentially increasing fracture risk. Direct evidence for the damaging effects of radiation on human bone are primarily demonstrated by the increased incidence of fractures at sites that absorb high doses of radiation during cancer therapy: exposures are considerably higher than what could be expected during spaceflight. However, both the rapidity of bone damage and the chronic nature of the changes appear similar between exposure scenarios. This review will outline our current knowledge of space and clinical exploration exposure to ionizing radiation on skeletal health. PMID:22826632

Willey, Jeffrey S.; Lloyd, Shane A.J.; Nelson, Gregory A.; Bateman, Ted A.

2011-01-01

211

Diagnosis of metabolic bone disease  

Microsoft Academic Search

This book presents a reference on the radiologic evaluation, features, and differential diagnosis of metabolic diseases involving the whole skeleton, calcium deficiencies resulting from pharmacologic agents, and bone changes related to endocrine disturbances. It also stresses how radiology, nuclear medicine, and biochemistry - either alone or in concert - contribute to clinical diagnosis. It covers renal bone disease, Paget's disease,

P. Grech; T. J. Martin; N. A. Barrington; P. J. Ell; I. FOGELMAN

1986-01-01

212

Interaction between Muscle and Bone  

PubMed Central

The clinical significance of sarcopenia and osteoporosis has increased with the increase in the population of older people. Sarcopenia is defined by decreased muscle mass and impaired muscle function, which is related to osteoporosis independently and dependently. Numerous lines of clinical evidence suggest that lean body mass is positively related to bone mass, which leads to reduced fracture risk. Genetic, endocrine and mechanical factors affect both muscle and bone simultaneously. Vitamin D, the growth hormone/insulin-like growth factor I axis and testosterone are physiologically and pathologically important as endocrine factors. These findings suggest the presence of interactions between muscle and bone, which might be very important for understanding the physiology and pathophysiology of sarcopenia and osteoporosis. Muscle/bone relationships include two factors: local control of muscle to bone and systemic humoral interactions between muscle and bone. As a putative local inducer of muscle ossification, we found Tmem119, a parathyroid hormone-responsive osteoblast differentiation factor. Moreover, osteoglycin might be one of the muscle-derived humoral bone anabolic factors. This issue may be important for the development of novel drugs and biomarkers for osteoporosis and sarcopenia. Further research will be necessary to clarify the details of the linkage of muscle and bone. PMID:24707465

2014-01-01

213

Understanding the Structure of Bones  

MedlinePLUS

Structural Organization of Bone The structure of bone is very similar to reinforced concrete that is used to make a building or a bridge. When the building ... the cement form a tight union, producing a structure that is strong and resilient enough to withstand ...

214

Ultrasonic guided waves in bone  

Microsoft Academic Search

Recent progress in quantitative ultrasound (QUS) has shown increasing interest toward measuring long bones by ultrasonic guided waves. This technology is widely used in the field of nondestructive testing and evaluation of different waveguide structures. Cortical bone provides such an elastic waveguide and its ability to sustain loading and resist fractures is known to be related to its mechanical properties

Petro Moilanen

2008-01-01

215

Bone health and prostate cancer  

Microsoft Academic Search

Bone metastases are a substantial burden to men with advanced prostate cancer as they often cause pain and can cause fractures and spinal cord compression. Osteoblasts and osteoclasts are both pathologically activated in the setting of prostate cancer bone metastases. As osteoclast activation is associated with disease progression, skeletal complications and death, osteoclast-targeted therapies are a rational approach to disease

P J Saylor; M R Smith

2010-01-01

216

Bone marrow mesenchymal stem cells and TGF-? signaling in bone remodeling  

PubMed Central

During bone resorption, abundant factors previously buried in the bone matrix are released into the bone marrow microenvironment, which results in recruitment and differentiation of bone marrow mesenchymal stem cells (MSCs) for subsequent bone formation, temporally and spatially coupling bone remodeling. Parathyroid hormone (PTH) orchestrates the signaling of many pathways that direct MSC fate. The spatiotemporal release and activation of matrix TGF-? during osteoclast bone resorption recruits MSCs to bone-resorptive sites. Dysregulation of TGF-? alters MSC fate, uncoupling bone remodeling and causing skeletal disorders. Modulation of TGF-? or PTH signaling may reestablish coupled bone remodeling and be a potential therapy. PMID:24487640

Crane, Janet L.; Cao, Xu

2014-01-01

217

Osteoporosis: Peak Bone Mass in Women  

MedlinePLUS

... Home Osteoporosis Women Osteoporosis: Peak Bone Mass in Women Publication available in: PDF (203 KB) Related Resources Fitness: Overtraining Risks Pregnancy, Nursing and Bone Health Osteoporosis ...

218

[Trauma of the temporal bone].  

PubMed

Temporal bone fractures are mostly due to high-energy head trauma with high rates of concurrent intracranial and cervical spine injuries and belong to the wider spectrum of lateral skull base trauma. Given that the temporal bone represents the most complex bone structure in the human body, containing a multitude of vital neurovascular structures, variable clinical presentations may arise from such fractures, ranging from asymptomatic courses to serious consequences, such as conductive and/or sensorineural hearing loss, vascular and/or cranial nerve injury as well as cerebrospinal fluid leakage. The present paper presents typical clinical sequelae and provides a detailed illustration of characteristic imaging findings related to temporal bone injury. Last but not least, in the final section of the manuscript the focus is placed on distinct anatomic structures which may mimic fracture lines and, thus, entail a high potential for misclassification as temporal bone fractures. PMID:24706249

Zimmer, A; Reith, W

2014-04-01

219

[Bone bruises of the knee].  

PubMed

Bone bruises represent a spectrum of occult bone lesions around the knee, which can only be detected by magnetic resonance imaging. These lesions can be isolated or are usually associated with other soft tissue injuries of the knee. These occult lesions are mostly associated with anterior cruciate ligament (ACL) injuries and are typically located in the lateral femoral condyle and the posterolateral tibial plateau. The location of the lesion may provide information on the mechanism of injury and associated soft tissue injuries. Bone bruises are less severe after low-energy trauma and most of these lesions usually regress within a short period. However, in lesions due to high-energy trauma like ACL injuries, healing may take years and those especially located close to the subchondral bone have the risk of associated osteochondral sequelae. Bone bruises may be responsible for the late degenerative changes of the knee after an ACL injury. PMID:18180591

Gönç, U?ur; Kayaalp, Asim; Irgit, Kaan

2007-01-01

220

Acoustic effects during bone ablation  

NASA Astrophysics Data System (ADS)

In surgical applications of lasers, it is often necessary to know when a laser has penetrated a bone. There are many instances when it is critical to avoid damaging tissue beneath the bone. We are developing a system to monitor the ablation of bone. We have found a method to detect when the bone has been penetrated by measuring the photo acoustic signal generated by a pulsed laser. Using a transducer on samples of temporal bone and several model substances, we can see a decrease in the power spectrum near 350 kHz as softer materials is ablated. The current results are from a carbon dioxide laser operating in the super pulse mode. We are developing the technique for use with the Vanderbilt Free Electron Laser as part of our computer assisted surgery techniques program.

Reinisch, Lou; Ossoff, Robert H.

1993-07-01

221

Denosumab: A bone antiresorptive drug.  

PubMed

Bone remodeling is the continuous process by which old bone is removed by bone-resorbing cells, the osteoclasts and replaced by new bone synthesized by bone forming cells, the osteoblasts. Osteoporosis is characterized by a progressive loss of bone mass and microarchitecture, which leads to increased fracture risk. Denosumab, a human monoclonal antibody resembling natural IgG2 immunoglobulin, has antiresorptive activity and is distinguished from other antiresorptive drugs. It mimics osteoprotegerin (OPG) that binds to RANKL and hence does not allow RANKL to bind with RANK receptor, thereby inhibiting osteoclast differentiation, activation and survival exerting primarily antiresorptive action. Denosumab trials have shown its efficacy in postmenopausal women with osteoporosis, unresectable giant cell tumor of bone and significant effect in non-metastatic prostate cancer and delay in the time-to-first skeletal related events (SRE) and subsequent SRE with denosumab than zoledronic acid in patients. It is available as 60 mg/ml in pre-filled syringes and approved for osteoporosis in postmenopausal women (60 mg s.c. twice yearly), unresectable giant cell tumor of bone in adults and skeletally mature adolescents (120 mh s.c. monthly), prevention of skeletal-related events and to increase bone mass in patients at high risk for fracture including androgen deprivation therapy for non-metastatic prostate cancer or adjuvant aromatase inhibitor therapy for breast cancer. Denosumab offers advantages of twice yearly dosing in osteoporosis and monthly dosing in giant cell tumor of bone with its novel mechanism of action and better tolerability. PMID:25609868

Dahiya, Navdeep; Khadka, Anjan; Sharma, A K; Gupta, A K; Singh, Nishith; Brashier, D B S

2015-01-01

222

[Bone and Calcium Research Update 2015. Regulation of bone remodeling by osteocytes].  

PubMed

Bone is constantly renewed by the balanced action of bone formation and bone resorption both of which mainly occur at the bone surface. This restructuring process called "bone remodeling" is important not only for normal bone mass and strength, but also for mineral homeostasis. An imbalance of bone remodeling is often linked to various bone diseases. During bone remodeling, resorption by osteoclasts precedes bone formation by osteoblasts. Based on the osteocyte location within the bone matrix and the cellular morphology, it is proposed that osteocytes potentially contribute to the controls of bone remodeling by sensing mechanical stress and hormones. Furthermore, bone has been traditionally regarded as a part of the skeletal and locomotor system, but recent studies suggest that osteocytes regulate systemic biological functions based on the inseparable link between bone and other systems. PMID:25530519

Nakashima, Tomoki

2015-01-01

223

Bone composition: relationship to bone fragility and antiosteoporotic drug effects  

PubMed Central

The composition of a bone can be described in terms of the mineral phase, hydroxyapatite, the organic phase, which consists of collagen type I, noncollagenous proteins, other components and water. The relative proportions of these various components vary with age, site, gender, disease and treatment. Any drug therapy could change the composition of a bone. This review, however, will only address those pharmaceuticals used to treat or prevent diseases of bone: fragility fractures in particular, and the way they can alter the composition. As bone is a heterogeneous tissue, its composition must be discussed in terms of the chemical makeup, properties of its chemical constituents and their distributions in the ever-changing bone matrix. Emphasis, in this review, is placed on changes in composition as a function of age and various diseases of bone, particularly osteoporosis. It is suggested that while some of the antiosteoporotic drugs can and do modify composition, their positive effects on bone strength may be balanced by negative ones. PMID:24501681

Boskey, Adele L

2013-01-01

224

Limb bone morphology, bone strength, and cursoriality in lagomorphs.  

PubMed

The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which 'cursorial specialization' affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and ?CT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high 'displacement advantage', permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing cursoriality, suggesting that the safety factor takes priority over locomotor economy in those regions of the postcranial skeleton that experience higher loading during locomotion. Overall, these findings support the hypothesis that cursoriality is associated with a common suite of morphological adaptations across a range of body sizes and radiations. PMID:25046350

Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

2014-10-01

225

A critical assessment of bone scan quantitation (bone to soft tissue ratios) in the diagnosis of metabolic bone disease  

Microsoft Academic Search

Accurate quantitation from the bone scan image of skeletal uptake of radiopharmaceutical would be of value in the assessment of patients with metabolic bone disease. Repeat measurements of bone to soft tissue (B\\/ST) ratios on the one set of images were made for 103 subjects, a) by the same observer using lumbar vertebra 2 for the area of bone; b)

Ignac Fogelman; Rodney G. Bessent; Derek Gordon

1981-01-01

226

Decreased bone area, bone mineral content, formative markers, and increased bone resorptive markers in endogenous Cushing's syndrome  

Microsoft Academic Search

It is well established that chronic excess of glucocorticoids has negative effects on bone and collagen turnover, and that secondary osteoporosis is a known clinical complication of endogenous Cushing's syndrome (CS). The aim of the present study was to evaluate bone dimension and bone mineral content in relation to biochemical markers of bone and collagen turnover, in a consecutive series

Kristin Godang; Thor Ueland; Jens Bollerslev

1999-01-01

227

Vitamin D and bone health.  

PubMed

Current data demonstrate that vitamin D deficiency contributes to the aetiology of at least two metabolic bone diseases, osteomalacia and osteoporosis. Osteomalacia, or rickets in children, results from a delay in mineralization and can be resolved by normalization of plasma calcium and phosphate homeostasis independently of vitamin D activity. The well characterized endocrine pathway of vitamin D metabolism and activities is solely responsible for vitamin D regulating plasma calcium and phosphate homeostasis and therefore for protecting against osteomalacia. In contrast a large body of clinical data indicate that an adequate vitamin D status as represented by the serum 25-hydroxyvitamin D concentration protects against osteoporosis by improving bone mineral density and reducing the risk of fracture. Interestingly adequate serum 1,25-dihydroxyvitamin D concentrations do not reduce the risk of fracture. In vitro human bone cell cultures and animal model studies indicate that 25-hydroxyvitamin D can be metabolised to 1,25-dihydroxyvitamin D by each of the major bone cells to activate VDR and modulate gene expression to reduce osteoblast proliferation and stimulate osteoblast and osteoclast maturation. These effects are associated with increased mineralization and decreased mineral resorption. Dietary calcium interacts with vitamin D metabolism at both the renal and bone tissue levels to direct either a catabolic action on bone through the endocrine system or an anabolic action through a bone tissue autocrine or paracrine system. PMID:22536765

Turner, Andrew G; Anderson, Paul H; Morris, Howard A

2012-01-01

228

Bone disease in burn patients.  

PubMed

Burn patients are at risk for bone disease due to aluminum (Al) exposure from use of antacids and albumin, partial immobilization, and increased production of endogenous glucocorticoids. Moreover, severely burned children are growth impaired up to 3 years after the burn. To determine the extent of bone disease, we studied nine men and three women, ages 18-41 years, with greater than 50% body surface area burn. Seven patients underwent iliac crest bone biopsy following double tetracycline labeling, one additional patient expired after a single label, and three others had postmortem specimens obtained for quantitative Al only. Serial serum and urine samples were obtained weekly until biopsy or death. All biopsied patients had reduced bone formation and osteoid area, surface, and width, with mineral apposition rate, osteoblast surface, and osteoclast number with normal eroded surfaces compared to age- and sex-matched normal ambulatory volunteers. Burn patients also had reduced bone formation, mineral apposition rate, osteoid area, and surface compared to age-matched volunteers at short-term bed rest. Serum levels of osteocalcin were low. Most patients had mild hypercalcemia but only a third had hypercalciuria. All patients had elevated Al in blood or urine; urine Al correlated inversely with serum osteocalcin. In 60% significant bone Al was detectable by stain or quantitation. Our data are compatible with burn patients having markedly reduced bone turnover. Al loading, partial immobilization, endogenous corticosteroids, and cytokine production may be among the etiologic factors. PMID:8456588

Klein, G L; Herndon, D N; Rutan, T C; Sherrard, D J; Coburn, J W; Langman, C B; Thomas, M L; Haddad, J G; Cooper, C W; Miller, N L

1993-03-01

229

Give the Dog a Bone  

NSDL National Science Digital Library

Ten bones are hidden in the squares of a blank 1-100 grid. Students are given the numbers of the squares one at a time. They attempt to locate the numbers in the hundreds chart and find all 10 bones within 60 seconds. Numbers of the incorrectly guessed squares are left in place to help with the search. The game helps students understand the structure and patterns of our base-10 number system. Children can be encouraged to make use of a found bone to locate the next one.

Cogan, Mark

2002-01-01

230

Gaucher disease and bone manifestations.  

PubMed

Gaucher disease is a relatively rare metabolic disease caused by the inherited deficiency of the lysosomal enzyme glucocerebrosidase. Gaucher disease affects multiple organs, among which is the skeleton. Bone involvement occurs frequently in Gaucher disease, and is one of its most debilitating features, reducing the quality of life of patients. Bone status is an important consideration for treatment to ameliorate symptoms and reduce the risk of irreversible complications. We have conducted a systematic review of all the various aspects of Gaucher disease, focusing on different skeletal manifestations, pathophysiology of bone alterations, clinical symptoms, and current diagnostic and therapeutic approaches. PMID:25377906

Marcucci, Gemma; Zimran, Ari; Bembi, Bruno; Kanis, John; Reginster, Jean-Yves; Rizzoli, Renè; Cooper, Cyrus; Brandi, Maria Luisa

2014-12-01

231

Pharmacological agents and bone healing  

PubMed Central

Osteoporosis is the most common alteration of bone metabolism. It derives from an increase in bone resorption with respect to bone formation and is characterized by microarchitectural alterations, decreased bone mass and increased risk of fracture. The coupling between bone formation and resorption is a fundamental concept in skeletal metabolism, and it explains how a certain amount of removed tissue can be replaced by the same amount of new bone. Various substances used to treat osteoporosis may also be used for orthopaedic conditions such as fracture healing, implant fixation, bone grafts and osteonecrosis. Fracture healing consists in the replacement of the lost bone by a tissue that has the same biomechanical properties as those preceding the fracture. The repair process is triggered by the local response to the tissue injury that damaged the continuity of bone. The duration of each phase of the healing process can vary significantly, depending on the site and characteristics of the fracture, on patient related factors and on the treatment choice. While most of the fractures heal with conventional treatment, they can also cause permanent damage and complications, especially in a certain kind of patients. Osteoporosis and old age may contribute in delaying or impairing the reparative process. In animal models the healing process is slower in older and/or ovariectomized animals. Biomechanical tests have also shown that bone strength is compromised in human osteoporotic cadaver bone. The same problems were highlighted in the surgical treatment of fractures in osteoporotic patients. Mainly in the treatment of hip fractures there is an increased risk of cut-out, re-fractures and implant failure in patients with osteoporosis. Preclinical studies have shown that certain pharmacological agents (bisphosphonates, strontium ranelate, teriparatide) may enhance osseointegration and stimulate reparative processes. They may be administered systemically and/or used locally at the fracture site on the implant surface. The aim of fracture treatment is to restore bone biomechanical properties and to allow restoring normal function at the affected site. If the new pharmacological approaches could be translated into clinical benefit and offered to patients with osteoporosis or other factors that put at risk the process of healing (subjects with severe loss of substance or fractures at high risk of complications), they could represent a valuable aid in the treatment of fractures. PMID:22461164

Tarantino, Umberto; Cerocchi, Irene; Celi, Monica; Scialdoni, Alessandro; Saturnino, Luca; Gasbarra, Elena

2009-01-01

232

Sticks and Stones Will Break That Bone!  

NSDL National Science Digital Library

Students learn about the strength of bones and methods of helping to mend fractured bones. During a class demonstration, a chicken bone is broken by applying a load until it reaches a point of failure (fracture). Then, working as biomedical engineers, students teams design their own splint or cast to help repair a fractured bone, learning about the strength of materials used.

Integrated Teaching And Learning Program

233

Bone island (enostosis): current concept — a review  

Microsoft Academic Search

An enostosis or bone island represents a focus of mature compact (cortical) bone within the cancellous bone (spongiosa). Thought by some to be a tumor-like condition and by others a hamartoma, this benign lesion is probably congenital or developmental in origin and reflects failure of resorption during endochondral ossification. A bone island can be virtually diagnosed based on its characteristic

Adam Greenspan

1995-01-01

234

Air-filled (Pneumatic) Bone Experiments  

NSDL National Science Digital Library

Just like birds, some dinosaurs had air-filled (pneumatic) bones, which made the dinosaurs' skeletons lighter. In this activity, learners bake chicken or turkey bones and then rub the ends off the bones with sandpaper to expose air spaces inside. This activity would be great during Thanksgiving vacation, or any other holiday when you have bones left over from dinner.

Lawrence Hall of Science

2005-01-01

235

Modeling Normal Aging Bone Loss, with Consideration of Bone Loss in Osteoporosis  

Microsoft Academic Search

A physiologically based model of normal bone loss in human aging is presented. The model is a modification of an existing physiologically based model of body and bone growth from birth to maturity. To account for loss of bone after peak bone mass is reached between ages 25 and 30 years, a slow first-order loss of bone is incorporated into

Ellen J. O'Flaherty

2000-01-01

236

Evolution of bone transplantation: molecular, cellular and tissue strategies to engineer human bone  

Microsoft Academic Search

Bone defects occur in a wide variety of clinical situations, and their reconstruction to provide mechanical integrity to the skeleton is a necessary step in the patient's rehabilitation. The current gold standard for bone reconstruction, the autogenous bone graft, works well in many circumstances. However, autograft reconstruction, along with the available alternatives of allogenous bone graft or poly(methylmethacrylate) bone cement,

Michael J. Yaszemski; Richard G. Payne; Wilson C. Hayes; Robert Langer; Antonios G. Mikos

1996-01-01

237

Noninvasive assessment of bone architecture by magnetic resonance micro-imaging-based virtual bone biopsy  

Microsoft Academic Search

The mechanical competence of trabecular bone, the type of bone constituting the vertebrae and ends of the long bones, is largely de- termined by the bone's volume fraction and architectural make-up. Experimental and clinical evidence suggests that up to 50% of tra- becular bone strength is determined by parameters characterizing the network's architecture. Although rarely clinically indicated be- cause of

Felix W. Wehrli; Punam K. Saha; Byron R. Gomberg; Hee Kwon Song

2003-01-01

238

Repair of bone defect using bone marrow cells and demineralized bone matrix supplemented with polymeric materials.  

PubMed

We present a novel, reverse thermo-responsive (RTR) polymeric osteogenic composite comprising demineralized bone matrix (DBM) and unmanipulated bone marrow cells (BMC) for repair of bone defects. The polymers investigated were low viscosity aqueous solutions at ambient temperature, which gel once they heat up and reach body temperature. Our goal to supplement DBM-BMC composite with RTR polymers displaying superior rheological properties, was to improve graft integrity and stability, during tissue regeneration. The osteogenic composite when implanted under kidney capsule of mice, proved to be biocompatible and biodegradable, with no residual polymer detected in the newly formed osteohematopoietic site. Implantation of the osteogenic composite into a large area of missing area of parietal bone of the skull of rats, resulted in an extensive remodeling of DBM particles, fully reconstituted hematopoietic microenvironment and well integrated normal flat bone within thirty days. The quality and shape of the newly created bone were comparable to the original bone and neither local or systemic inflammatory reactions nor fibrosis at the junction of the new and old calvarium could be documented. Furthermore, combined laser capture microdissection (LCM) technique and PCR analysis of male BMC in female rats confirmed the presence of male derived cells captured from the repaired/ regenerated flat bone defect. The use of active self sufficient osteogenic DBM-BMC composite supported by a viscous polymeric scaffold for purposive local hard tissue formation, may have a significant potential in enhancement of bone regeneration and repair following trauma, degenerative or inflamatory lesion, iatrogenic interventions and cosmetic indications. PMID:19807659

Kurkalli, Basan Gowda S; Gurevitch, Olga; Sosnik, Alejandro; Cohn, Daniel; Slavin, Shimon

2010-03-01

239

Metallic materials stimulating bone formation.  

PubMed

Metallic materials implanted into bone defects are generally encapsulated by a fibrous tissue. Some metallic materials such as titanium and tantalum, however, have been revealed to bond to the living bone without forming the fibrous tissue, when they were subjected to NaOH solution and heat treatments. Thus treated metals form bone tissue around them even in muscle, when they take a porous form. This kind of osteoconductive and osteoinductive properties are attributed to sodium titanate or tantalate layer on their surfaces formed by the NaOH and heat treatments. These layers induce the deposition of bonelike apatite on the surface of the metals in the living body. This kind of bioactive metals are useful as bone substitutes even highly loaded portions, such as hip joint, spine and tooth root. PMID:15468833

Kokubo, T

2004-05-01

240

Inhaled Corticosteroids and Bone Health  

PubMed Central

Inhaled corticosteroids (ICS) are the cornerstones in the management of bronchial asthma and some cases of chronic obstructive pulmonary disease. Although ICS are claimed to have low side effect profiles, at high doses they can cause systemic adverse effects including bone diseases such as osteopenia, osteoporosis and osteonecrosis. Corticosteroids have detrimental effects on function and survival of osteoblasts and osteocytes, and with the prolongation of osteoclast survival, induce metabolic bone disease. Glucocorticoid-induced osteoporosis (GIO) can be associated with major complications such as vertebral and neck of femur fractures. The American College of Rheumatology (ACR) published criteria in 2010 for the management of GIO. ACR recommends bisphosphonates along with calcium and vitamin D supplements as the first-line agents for GIO management. ACR recommendations can be applied to manage patients on ICS with a high risk of developing metabolic bone disease. This review outlines the mechanisms and management of ICS-induced bone disease.

Chee, Carolyn; Sellahewa, Luckni; Pappachan, Joseph M

2014-01-01

241

[Bone metastases treated with radiopharmaceuticals].  

PubMed

The administration of a radionuclide in unsealed source whose radiation will destroy cells that have selectively accumulated product is called radiometabolic therapy. The management of bone pain is a major problem, particularly in cases of breast or prostate where the presence of metastases can remain compatible with long-term survival of cancer patients. In this context, the radiometabolic therapy reduces the pain secondary to bone metastases, in association or not with analgesics. This technique is rarely prescribed as first-line. It can also be combined with external beam radiotherapy or chemotherapy, if clinical conditions permit (due to the increased risk of hematologic toxicity). In this setting, the currently used substances are Metastron® and Quadramet®. Recently, a new product, radium chloride (or Alpharadin®) has shown efficacy in bone metastases from prostate cancer, particularly in terms of bone pain palliation, but also of increased overall survival. In addition, this product has virtually no hematologic toxicity. PMID:24409472

Giammarile, Francesco

2013-11-01

242

Pregnancy, Breastfeeding, and Bone Health  

MedlinePLUS

... supported by your browser. Home Osteoporosis Women Pregnancy, Breastfeeding, and Bone Health Publication available in: PDF (233 ... Anorexia Nervosa Partner Resources An Easy Guide to Breastfeeding (OWH) Pregnancy and Medications (OWH) Prenatal Care (OWH)

243

Bone biopsy in haematological disorders.  

PubMed Central

Bone marrow biopsies are now widely used in the investigation and follow-up of many diseases. Semi-thin sections of 8216 undecalcified biopsies of patients with haematological disorders were studied. Observations were made on the cytopenias and the myelodysplastic syndromes, the acute leukaemias the myeloproliferative disorders, Hodgkin's disease and the malignant lymphomas including multiple myeloma, hairy cell leukaemia and angioimmunoblastic lymphadenopathy. Bone marrow biopsies are essential for the differential diagnosis of most cytopenias and for the early recognition of fibrosis which most frequently occurred as a consequence of megakaryocytic proliferation in the myeloproliferative disorders. Different patterns of bone marrow involvement were found in the lymphoproliferative disorders and both their type and extent constituted factors of prognostic significance. A survey of the literature is given and the conclusion is drawn that bone marrow biopsies provide indispensible information for the diagnostic evaluation and the follow-up of patients with haematological disorders. Images PMID:7040489

Burkhardt, R; Frisch, B; Bartl, R

1982-01-01

244

JAMA Patient Page: Bone Fractures  

MedlinePLUS

... Fixator With Pins and Wires Intramedullary Nail Cast Internal Fixation External Fixation Simple Fracture, Displaced Comminuted Fracture Simple ... the bones have healed, the pins are removed. • Internal fixation—In a surgical procedure, metal rods, wires, or ...

245

Drugs Approved for Bone Cancer  

Cancer.gov

This page lists cancer drugs approved by the Food and Drug Administration (FDA) for bone cancer. The list includes generic names and brand names. The drug names link to NCI's Cancer Drug Information summaries.

246

Bare Bones of Bioactive Glass  

NASA Technical Reports Server (NTRS)

Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Bioactive glass particles (left) with a microporous surface (right) are widely accepted as a synthetic material for periodontal procedures. Using the particles to grow three-dimensional tissue cultures may one day result in developing an improved, more rugged bone tissue that may be used to correct skeletal disorders and bone defects. The work is sponsored by NASA's Office of Biological and Physical Research.

2000-01-01

247

Inherited Bone Marrow Failure Syndromes  

MedlinePLUS

What are the IBMFS disorders? Amegakaryocytic Thrombocytopenia Diamond-Blackfan Anemia Dyskeratosis Congenita Fanconi Anemia Pearson Syndrome Severe Congenital Neutropenia Shwachman-Diamond Syndrome Thrombocytopenia Absent Radii Other Bone Marrow Failure Syndromes Amegakaryocytic ...

248

Aspiration and Biopsy: Bone Marrow  

MedlinePLUS

... aspiration and biopsy, you can speak with your nurse or doctor before the procedure. Reviewed by: Yamini Durani, MD Date reviewed: April ... Cell Transplants Anemia Biopsy Leukemia Word! Bone Marrow About ...

249

Issues in modern bone histomorphometry?  

PubMed Central

This review reports on proceedings of a bone histomorphometry session conducted at the Fortieth International IBMS Sun Valley Skeletal Tissue Biology Workshop held on August 1, 2010. The session was prompted by recent technical problems encountered in conducting histomorphometry on bone biopsies from humans and animals treated with anti-remodeling agents such as bisphosphonates and RANKL antibodies. These agents reduce remodeling substantially, and thus cause problems in calculating bone remodeling dynamics using in vivo fluorochrome labeling. The tissue specimens often contain few or no fluorochrome labels, and thus create statistical and other problems in analyzing variables such as mineral apposition rates, mineralizing surface and bone formation rates. The conference attendees discussed these problems and their resolutions, and the proceedings reported here summarize their discussions and recommendations. PMID:21810491

Recker, R.R.; Kimmel, D.B.; Dempster, D.; Weinstein, R.S.; Wronski, T.J.; Burr, D.B.

2012-01-01

250

Biomaterials as Scaffold for Bone Tissue Engineering  

Microsoft Academic Search

Almost 20 years after the invention of tissue engineering, autogenous bone grafting has remained the favored strategy for\\u000a the treatment of bone defects. As an alternative, a vast variety of bone substitutes has been developed and is available for\\u000a clinical use. The ongoing search for bone substitutes, however, reflects the limitations imposed to both autogenous and allogenous\\u000a bone grafts as

Matthias Schieker; Hermann Seitz; Inga Drosse; Sebastian Seitz; Wolf Mutschler

2006-01-01

251

Research opportunities in bone demineralization, phase 3  

NASA Technical Reports Server (NTRS)

An overview of bone demineralization during space flight, observations in bone demineralization and experiments related to bone loss planned for Spacelab flights, and suggestions for further research are investigated. The observations of the working group focused upon the following topics: (1) pathogenesis of bone demineralization, (2) potential for occurrence of renal stones consequent to prolonged hypercalciuria, (3) development of appropriate ground based and inflight models to study bone demineralization, (4) integration of research efforts, and (5) development of effective countermeasures.

Anderson, S. A. (editor); Cohn, S. H. (editor)

1984-01-01

252

Percutaneous osteoplasty in treatment of bone lymphangiomatosis.  

PubMed

Primary bone lymphangiomatosis is a disease of unknown etiology that can cause lytic lesions in long bones, the pelvis, the spinal column and the cranium. We are presenting the case of a woman with localized bone lymphangiomatosis in the left knee. The authors believe this is the first case in which percutaneous osteoplasty was used in long bones for the treatment of bone lesions resulting from this disease showing good clinical results. PMID:24133314

Mifsut, Damián; Renovell, Pablo; Gomar, Francisco; Saravia, Marcos

2013-09-01

253

Percutaneous osteoplasty in treatment of bone lymphangiomatosis  

PubMed Central

Primary bone lymphangiomatosis is a disease of unknown etiology that can cause lytic lesions in long bones, the pelvis, the spinal column and the cranium. We are presenting the case of a woman with localized bone lymphangiomatosis in the left knee. The authors believe this is the first case in which percutaneous osteoplasty was used in long bones for the treatment of bone lesions resulting from this disease showing good clinical results. PMID:24133314

Mifsut, Damián; Renovell, Pablo; Gomar, Francisco; Saravia, Marcos

2013-01-01

254

Mechanical Loading: Bone Remodeling and Cartilage Maintenance  

Microsoft Academic Search

Bone remodeling and cartilage maintenance are strongly influenced by biomechanical signals generated by mechanical loading.\\u000a Although moderate loading is required to maintain bone mass and cartilage homeostasis, loading can cause deleterious effects\\u000a such as bone fracture and cartilage degradation. Because a tight coupling exists between cartilage and bone, alterations in\\u000a one tissue can affect the other. Bone marrow lesions are

Hiroki Yokota; Daniel J. Leong; Hui B. Sun

255

Receptor tyrosine kinase inhibition causes simultaneous bone loss and excess bone formation within growing bone in rats  

SciTech Connect

During postnatal skeletal growth, adaptation to mechanical loading leads to cellular activities at the growth plate. It has recently become evident that bone forming and bone resorbing cells are affected by the receptor tyrosine kinase (RTK) inhibitor imatinib mesylate (STI571, Gleevec (registered)) . Imatinib targets PDGF, ABL-related gene, c-Abl, c-Kit and c-Fms receptors, many of which have multiple functions in the bone microenvironment. We therefore studied the effects of imatinib in growing bone. Young rats were exposed to imatinib (150 mg/kg on postnatal days 5-7, or 100 mg/kg on postnatal days 5-13), and the effects of RTK inhibition on bone physiology were studied after 8 and 70 days (3-day treatment), or after 14 days (9-day treatment). X-ray imaging, computer tomography, histomorphometry, RNA analysis and immunohistochemistry were used to evaluate bone modeling and remodeling in vivo. Imatinib treatment eliminated osteoclasts from the metaphyseal osteochondral junction at 8 and 14 days. This led to a resorption arrest at the growth plate, but also increased bone apposition by osteoblasts, thus resulting in local osteopetrosis at the osteochondral junction. The impaired bone remodelation observed on day 8 remained significant until adulthood. Within the same bone, increased osteoclast activity, leading to bone loss, was observed at distal bone trabeculae on days 8 and 14. Peripheral quantitative computer tomography (pQCT) and micro-CT analysis confirmed that, at the osteochondral junction, imatinib shifted the balance from bone resorption towards bone formation, thereby altering bone modeling. At distal trabecular bone, in turn, the balance was turned towards bone resorption, leading to bone loss. - Research Highlights: > 3-Day imatinib treatment. > Causes growth plate anomalies in young rats. > Causes biomechanical changes and significant bone loss at distal trabecular bone. > Results in loss of osteoclasts at osteochondral junction.

Nurmio, Mirja, E-mail: Mirja.Nurmio@utu.fi [Department of Physiology, University of Turku (Finland); Department of Pediatrics, University of Turku (Finland); Joki, Henna, E-mail: Henna.Joki@utu.fi [Department of Cell Biology and Anatomy, University of Turku (Finland); Kallio, Jenny, E-mail: Jenny.Kallio@utu.fi [Department of Physiology, University of Turku (Finland); Maeaettae, Jorma A., E-mail: jorma.maatta@utu.fi [Department of Cell Biology and Anatomy, University of Turku (Finland); Department of Turku Center for Disease Modeling, University of Turku (Finland); Vaeaenaenen, H. Kalervo, E-mail: kalervo.vaananen@utu.fi [Department of Cell Biology and Anatomy, University of Turku (Finland); Toppari, Jorma, E-mail: Jorma.Toppari@utu.fi [Department of Physiology, University of Turku (Finland); Department of Pediatrics, University of Turku (Finland); Jahnukainen, Kirsi, E-mail: Kirsi.Jahnukainen@utu.fi [Pediatric Endocrinology Unit, Department of Woman and Child Health, Karolinska Institutet and University Hospital, Stockholm (Sweden); Division of Hematology-Oncology and Stem Cell Transplantation, Hospital for Children and Adolescents, Helsinki (Finland); Laitala-Leinonen, Tiina, E-mail: tilale@utu.fi [Department of Cell Biology and Anatomy, University of Turku (Finland)

2011-08-01

256

Growth factors in bone repair  

Microsoft Academic Search

The role of growth factors (GF) in bone repair is widely recognised, particularly for bone morphogenetic proteins (BMPs),\\u000a fibroblast growth factor (FGF), insulin-like growth factors (IGFs), platelet-derived growth factor (PDGF), transforming growth\\u000a factor-? (TGF-?) and vascular endothelial growth factor (VEGF). GF are usually stored in the extracellular matrix (ECM), but\\u000a after injury are actively released by ECM, cells and platelets.

Valentina Devescovi; Elisa Leonardi; Gabriela Ciapetti; Elisabetta Cenni

2008-01-01

257

Unsuspected pregnancy during bone scintigraphy  

SciTech Connect

Despite careful screening efforts to avoid it, nuclear medicine studies are unintentionally performed on pregnant patients. Three-phase bone scanning is a common procedure performed in women of child-bearing age. Unsuspected pregnancies have been discovered on the flow and early view of the pelvis. The authors present a case of a pregnant girl, aged 15, who had a bone scan. They explain how this occurred and how they plan to prevent a recurrence. Dosimetry for the fetus also is considered.

Oates, E.; Ramberg, K.; Becker, J.L. (Tufts-New England Medical Center, Boston, MA (USA))

1990-06-01

258

Metabolic bone disease in IBD  

Microsoft Academic Search

A substantial number of patients with inflammatory bowel disease (IBD) will manifest extra-intestinal complications. Metabolic\\u000a bone disease and arthropathies are among the most debilitating of these. Decreased bone mineral density and increased fracture\\u000a risk may occur in relation to the underlying disease itself or result from vitamin, mineral, and hormonal deficiencies; medications\\u000a used to treat the underlying disease; lifestyle; and

Ivelisse Lopez; Alan L. Buchman

2000-01-01

259

The cartilage-bone interface.  

PubMed

In the knee joint, the purpose of the cartilage-bone interface is to maintain structural integrity of the osteochondral unit during walking, kneeling, pivoting, and jumping--during which tensile, compressive, and shear forces are transmitted from the viscoelastic articular cartilage layer to the much stiffer mineralized end of the long bone. Mature articular cartilage is integrated with subchondral bone through a approximately 20 to approximately 250 microm thick layer of calcified cartilage. Inside the calcified cartilage layer, perpendicular chondrocyte-derived collagen type II fibers become structurally cemented to collagen type I osteoid deposited by osteoblasts. The mature mineralization front is delineated by a thin approximately 5 microm undulating tidemark structure that forms at the base of articular cartilage. Growth plate cartilage is anchored to epiphyseal bone, sometimes via a thin layer of calcified cartilage and tidemark, while the hypertrophic edge does not form a tidemark and undergoes continual vascular invasion and endochondral ossification (EO) until skeletal maturity upon which the growth plates are fully resorbed and replaced by bone. In this review, the formation of the cartilage-bone interface during skeletal development and cartilage repair, and its structure and composition are presented. Animal models and human anatomical studies show that the tidemark is a dynamic structure that forms within a purely collagen type II-positive and collagen type I-negative hyaline cartilage matrix. Cartilage repair strategies that elicit fibrocartilage, a mixture of collagen type I and type II, are predicted to show little tidemark/calcified cartilage regeneration and to develop a less stable repair tissue-bone interface. The tidemark can be regenerated through a bone marrow-driven growth process of EO near the articular surface. PMID:22928426

Hoemann, Caroline D; Lafantaisie-Favreau, Charles-Hubert; Lascau-Coman, Viorica; Chen, Gaoping; Guzmán-Morales, Jessica

2012-05-01

260

Guided Waves in Cortical Bone  

Microsoft Academic Search

\\u000a In the last decade, several experimental studies have shown that long cortical bones act as a natural waveguide at ultrasonic\\u000a frequencies despite attenuation in bone material and heterogeneity in elastic and geometrical properties. Propagation in waveguides\\u000a consists in a variety of dispersive waves, each one with its own frequency-dependent field distribution across the section\\u000a of the waveguide. Guided waves are

Maryline Talmant; Josquin Foiret; Jean-Gabriel Minonzio

261

Bone Metastasis and Pathological Fractures  

Microsoft Academic Search

Bone metastasis commonly occurs in association with solid malignant tumors such as breast, prostate, lung, and renal cancers\\u000a (1–5). Thirty to seventy percent of cancer patients have skeletal metastasis (6), making the axial skeleton the third most common site for metastasis after lung and liver. Because all of these cancers\\u000a (breast, prostate, lung, and renal) are common, metastatic bone lesions

Laurie A. McDuffee; Nigel Colterjohn; Gurmit Singh

262

Giant cell tumor of bone.  

PubMed

Giant cell tumor (GCT) of bone is one type of giant cell-rich lesion of bone. This benign mesenchymal tumor has characteristic multinuclear giant cells. Mononuclear stromal cells are the physiologically active and diagnostic cell type. Most GCTs are located in the epiphyseal regions of long bones. The axial skeleton-primarily the sacrum-is a secondary site of involvement. Most patients present with pain, swelling, joint effusion, and disability in the third and fourth decades of life. Imaging studies are important for tumor staging and radiographic grading. Typically, these clinically active but slow-growing tumors are confined to bone, with relatively well-defined radiographic borders. Monostotic disease is most common. Metastatic spread to the lungs is rare. Extended intralesional curettage with or without adjuvant therapy is the primary treatment choice. Local recurrence is seen in ? 20% of cases, and a second local intralesional procedure is typically sufficient in cases that are detected early. Medical therapies include diphosphonates and denosumab. Denosumab has been approved for use in osteoporosis as well as breast and prostate cancer metastatic to bone. Medical therapy and radiotherapy can alter the management of GCT of bone, especially in multifocal disease, local recurrences, and bulky central/axial disease. PMID:23378375

Raskin, Kevin A; Schwab, Joseph H; Mankin, Henry J; Springfield, Dempsey S; Hornicek, Francis J

2013-02-01

263

The nature of bone carbonate.  

PubMed

Models of the bone salt and its synthetic analogues have been strenuously, and sometimes emotionally debated since the late nineteenth century. The main protagonist in the drama is the ubiquitous CO3=ion whose role has never been clearly understood. Initially regarded as an essential part of the calcium phosphate crystal complex, it came to be dubiously designated as a separate phase CaCO3, as an adsorbed ion, or even as a mere contaminant. More recent studies provide evidence that the original impression may be more nearly correct. Of particular interest in defining the role of CO3= in bone are the reactions involved in the formation of CO3-apatite under conditions approximating the physiological. These observations suggest that the synthesis of bone mineral involves hydrolysis of an initial acidic calcium phosphate precipitate to octacalcium phosphate, which is then converted to octacalcium phosphate carbonate (OCPC) by virtue of the replacement of PO4 identical to (HPO4=) by CO3=. OCPC satisfies many criteria for a satisfactory definition of the nature of the bone mineral. It can explain its solubility behavior and the intrinsic relationship between PO4 identical to (HPO4=) and CO3=, the normal variations in bone composition, the sequence of events in bone mineral maturation, and the loss of CO3= under normal and pathological conditions. PMID:608288

Biltz, R M; Pellegrino, E D

1977-01-01

264

Effects of ipriflavone on perialveolar bone formation.  

PubMed

The effect of ipriflavone (IP), a synthetic isoflavonoid derivative, on in vivo bone formation was studied in rat perialveolar bone by surgically producing a hole in the mandibular bone. The holes were filled either with powdered IP or with compounds containing no osteoinductive properties such as biostite and Htr (hard tissue replacement). In control animals, the holes were left to heal spontaneously. The animals were killed 3, 28, and 40 days after surgery and a detailed morphological and morphometric study was performed on the perialveolar bone surrounding the wounds. Three days after surgery (inflammatory phase) the bone wounds were occupied by hemorragic and inflammatory cells in both the untreated and IP-treated bone defects. Twenty-eight days after surgery, bone formation was evident with new bone spiculae particularly concentrated in the area of the bone lesion closest to the adjacent periodontal ligament. Morphometric measurements of the areas occupied by new bone showed that the synthesis of perialveolar bone was significantly stimulated by IP. The repair of the bone defects by new bone formation progressed by day 40, but only in the presence of IP were the original holes almost completely repaired. Conversely, biostite and Htr did not influence promotion of new bone formation. In conclusion, the results of the present study are consistent with a role of IP in stimulating osteogenesis and suggest that this compound could represent a potential therapeutic tool to promote repair of injured perialveolar bone. PMID:9744990

Martini, M; Formigli, L; Tonelli, P; Giannelli, M; Amunni, F; Naldi, D; Brandi, M L; Zecchi Orlandini, S; Orlandini, G E

1998-10-01

265

Comparable bone healing capacity of different bone graft matrices in a rabbit segmental defect model  

PubMed Central

We compared the bone healing capacity of three different demineralized bone matrix (DBM) products applied using different carrier molecules (hyaluronic acid [HA] vs. carboxymethylcellulose [CMC]) or bone compositions (cortical bone vs. cortical bone and cancellous bone) in a rabbit segmental defect model. Overall, 15-mm segmental defects in the left and right radiuses were created in 36 New Zealand White rabbits and filled with HA-based demineralized cortical bone matrix (DBX), CMC-based demineralized cortical bone matrix (DB) or CMC-based demineralized cortical bone with cancellous bone (NDDB), and the wound area was evaluated at 4, 8, and 12 weeks post-implantation. DBX showed significantly lower radiopacity, bone volume fraction, and bone mineral density than DB and NDDB before implantation. However, bone healing score, bone volume fraction, bone mineral density, and residual bone area at 4, 8, and 12 weeks post-implantation revealed no significant differences in bone healing capacity. Overall, three DBM products with different carrier molecules or bone compositions showed similar bone healing capacity. PMID:24675830

Kim, Jong Min; Kim, Myoung Hwan; Kang, Seong Soo; Kim, Gonhyung

2014-01-01

266

Posttraumatic Frontal Bone Osteomyelitis  

PubMed Central

We present the clinical case of a patient with open bilateral frontal sinus fractures who developed a frontal osteomyelitis. A review of the problem and management ascending to the different alternatives for central anterior skull base defects and fronto-orbital reconstruction is also presented. After extensive radical debridement of the necrotic bone, final reconstruction of the skull base was performed by using a rectus abdominis free flap. A custom-made hard tissue replacement implant was used for the fronto-orbital reconstruction. Extensive debridement is required for the treatment of frontal osteomyelitis. An appropriate isolation of the skull base from the upper aerodigestive system must be obtained to prevent continuous infectious complications. Free flaps are especially useful for skull base reconstruction when traditional methods are not available or have failed because of the lack of available tissue for vascularized reconstruction. Custom-made alloplastic implants are a good reconstructive option for large fronto-orbital defects once the infection is gone and vascularized tissue has been transferred. PMID:22110798

Jung, S. Heredero; Aniceto, G. Sánchez; Rodríguez, I. Zubillaga; Diaz, R. Gutiérrez; Recuero, I.I. García

2009-01-01

267

Bioactive silica based nanoparticles stimulate bone forming osteoblasts, suppress bone esorbing osteoclasts, and enhance bone mineral density in vivo  

PubMed Central

Bone is a dynamic tissue that undergoes renewal throughout life by a process whereby osteoclasts resorb worn bone and osteoblasts synthesize new bone. Imbalances in bone turnover lead to bone loss and development of osteoporosis and ultimately fracture, a debilitating condition with high morbidity and mortality. Silica is a ubiquitous biocontaminant that is considered to have high biocompatibility. We report that silica nanoparticles mediate potent inhibitory effects on osteoclasts and stimulatory effects on osteoblasts in vitro. The mechanism of bioactivity is a consequence of an intrinsic capacity to antagonize activation of NF-?B, a signal transduction pathway required for osteoclastic bone resorption, but inhibitory to osteoblastic bone formation. We further demonstrate that silica nanoparticles promote a significant enhancement of bone mineral density (BMD) in mice in vivo providing a proof of principle for the potential application of silica nanoparticles as a pharmacological agent to enhance BMD and protect against bone fracture. PMID:22100753

Beck, George R.; Ha, Shin-Woo; Camalier, Corinne E.; Yamaguchi, Masayoshi; Li, Yan; Lee, Jin-Kyu; Weitzmann, M. Neale

2011-01-01

268

Spine bone texture assessed by trabecular bone score (TBS) to evaluate bone health in thalassemia major.  

PubMed

Due to the increasing survival of thalassemic patients, osteopathy is a mounting clinical problem. Low bone mass alone cannot account for the high fracture risk described; impaired bone quality has been speculated but so far it cannot be demonstrated noninvasively. We studied bone quality in thalassemia major using trabecular bone score (TBS), a novel texture measurement extracted from spine dual-energy X-ray absorptiometry (DXA), proposed in postmenopausal and secondary osteoporosis as an indirect index of microarchitecture. TBS was evaluated in 124 adult thalassemics (age range 19-56 years), followed-up with optimal transfusional and therapeutical regimens, and in 65 non-thalassemic patients (22-52 years) undergoing DXA for different bone diseases. TBS was lower in thalassemic patients (1.04 ± 0.12 [range 0.80-1.30]) versus controls (1.34 ± 0.11 [1.06-1.52]) (p < 0.001), and correlated with BMD. TBS and BMD values correlated with age, indicating that thalassemia negatively affects both bone quality and quantity, especially as the patient gets older. TBS was 1.02 ± 0.11 [0.80-1.28] in the osteoporotic thalassemic patients, 1.08 ± 0.12 [0.82-1.30] in the osteopenic ones and 1.15 ± 0.10 [0.96-1.26] in those with normal BMD. No gender differences were found (males: 1.02 ± 0.13 [0.80-1.30], females 1.05 ± 0.11 [0.80-1.30]), nor between patients with and without endocrine-metabolic disorders affecting bone metabolism. Our findings from a large population with thalassemia major show that TBS is a valuable tool to assess noninvasively bone quality, and it may be related to fragility fracture risk in thalassemic osteopathy. PMID:25348077

Baldini, M; Ulivieri, F M; Forti, S; Serafino, S; Seghezzi, S; Marcon, A; Giarda, F; Messina, C; Cassinerio, E; Aubry-Rozier, B; Hans, D; Cappellini, M D

2014-12-01

269

Differential Effects of Bone Mineral Content and Bone Area on Vertebral Strength in a Swine Model  

Microsoft Academic Search

.   Since the biomechanical competence of a vertebral body may be closely related to the content and distribution of the bone\\u000a mineral, we have evaluated the effects of projected vertebral bone area (BA) and bone mineral parameters [bone mineral content\\u000a (BMC) or bone mineral density (BMD)] on their biomechanical competence. We used dual-energy X-ray absorptiometry (DXA) to\\u000a assess the bone

R.-S. Yang; S.-S. Wang; H.-J. Lin; T.-K. Liu; Y.-S. Hang; K.-S. Tsai

1998-01-01

270

21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.  

Code of Federal Regulations, 2010 CFR

... Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be...

2010-04-01

271

21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.  

Code of Federal Regulations, 2014 CFR

... Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be...

2014-04-01

272

21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.  

Code of Federal Regulations, 2012 CFR

... Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be...

2012-04-01

273

21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.  

Code of Federal Regulations, 2013 CFR

... Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be...

2013-04-01

274

21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.  

Code of Federal Regulations, 2011 CFR

... Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device intended to be...

2011-04-01

275

Remineralized bone matrix as a scaffold for bone tissue engineering.  

PubMed

There is a need for improved biomaterials for use in treating non-healing bone defects. A number of natural and synthetic biomaterials have been used for the regeneration of bone tissue with mixed results. One approach is to modify native tissue via decellularization or other treatment for use as natural scaffolding for tissue repair. In this study, our goal was to improve on our previously published alternating solution immersion (ASI) method to fabricate a robust, biocompatible, and mechanically competent biomaterial from natural demineralized bone matrix (DBM). The improved method includes an antigen removal (AR) treatment step which improves mineralization and stiffness while removing unwanted proteins. The chemistry of the mineral in the remineralized bone matrix (RBM) was consistent with dicalcium phosphate dihydrate (brushite), a material used clinically in bone healing applications. Mass spectrometry identified proteins removed from the matrix with AR treatment to include ?-2 HS-glycoprotein and osteopontin, noncollagenous proteins (NCPs) and known inhibitors of biomineralization. Additionally, the RBM supported the survival, proliferation, and differentiation of human mesenchymal stromal cells (MSCs) in vitro as well or better than other widely used biomaterials including DBM and PLG scaffolds. DNA content increased more than 10-fold on RBM compared to DBM and PLG; likewise, osteogenic gene expression was significantly increased after 1 and 2 weeks. We demonstrated that ASI remineralization has the capacity to fabricate mechanically stiff and biocompatible RBM, a suitable biomaterial for cell culture applications. PMID:24616346

Soicher, Matthew A; Christiansen, Blaine A; Stover, Susan M; Leach, J Kent; Yellowley, Clare E; Griffiths, Leigh G; Fyhrie, David P

2014-12-01

276

Bone loss or lost bone: rationale and recommendations for the diagnosis and treatment of early postmenopausal bone loss.  

PubMed

Recent reports suggest that bone loss begins during late perimenopause at a dramatic rate, even before estrogen levels plummet. During the ensuing 5 years, there is evidence of the beginnings of microarchitectural deterioration, which impacts bone strength and ultimately enhances its propensity to fracture. The diagnosis of osteoporosis based on T-scores alone, or through stratification for a high fracture risk by FRAX, excludes these women who are rapidly losing bone. Because all antiosteoporosis therapies, in particular bisphosphonates, reduce bone loss, we propose aggressive, likely short-term therapy with a goal to reduce bone loss, stabilize bone density, and prevent microarchitectural deterioration. PMID:19968915

Zaidi, Mone; Turner, Charles H; Canalis, Ernesto; Pacifici, Roberto; Sun, Li; Iqbal, Jameel; Guo, X Edward; Silverman, Stuart; Epstein, Solomon; Rosen, Clifford J

2009-12-01

277

Method for improved prediction of bone fracture risk using bone mineral density in structural analysis  

NASA Technical Reports Server (NTRS)

A non-invasive in-vivo method of analyzing a bone for fracture risk includes obtaining data from the bone such as by computed tomography or projection imaging which data represents a measure of bone material characteristics such as bone mineral density. The distribution of the bone material characteristics is used to generate a finite element method (FEM) mesh from which load capability of the bone can be determined. In determining load capability, the bone is mathematically compressed, and stress, strain force, force/area versus bone material characteristics are determined.

Cann, Christopher E. (Inventor); Faulkner, Kenneth G. (Inventor)

1992-01-01

278

Changing measures to evaluate changing bone.  

PubMed

Osteoporosis is a silent, progressive disease affecting millions of Americans, costing $23.5 billion annually (). Fragility fractures, painful and costly sequelae of osteoporosis, are frequently underdiagnosed and undertreated partially because of limited assessment measures. Currently, bone mineral density measured by dual-energy x-ray absorptiometry is the surrogate marker of bone health () but has shortcomings predicting fragility fractures. Bone turnover markers and magnetic resonance spectroscopy are promising techniques for earlier, more accurate assessment of bone physiology and structure. Bone turnover markers reflect the dynamic nature of living bone (), thus providing a more comprehensive picture of bone health. Magnetic resonance spectroscopy may hold predictive power in determining fast and slow bone mineral density losers (). The use of these tools may assist with diagnosis of osteoporosis, allowing earlier determination of the effectiveness of prescribed therapies to improve bone health. PMID:25607615

Fitton, Lori; Astroth, Kim Schafer; Wilson, Denise

2015-01-01

279

Regulation of postnatal bone homeostasis by TGF?  

PubMed Central

Perhaps more so than any other tissue, bone has pivotal mechanical and biological functions. Underlying the ability of bone to execute these functions, whether providing structural support or preserving mineral homeostasis, is the dynamic remodeling of bone matrix. Cells within bone integrate multiple stimuli to balance the deposition and resorption of bone matrix. Transforming growth factor-? (TGF?) uniquely coordinates bone cell activity to maintain bone homeostasis. TGF? regulates the differentiation and function of both osteoblasts and osteoclasts, from lineage recruitment to terminal differentiation, to balance bone formation and resorption. TGF? calibrates the synthesis and material quality of bone matrix and bone's responsiveness to applied mechanical loads. Therefore, by coupling the activity of bone forming and resorbing cells, and by sensing, responding to and defining physical cues, TGF? integrates physical and biochemical stimuli to maintain bone homeostasis. Disruption of TGF? signaling has significant consequences on bone mass and quality. Alternatively, TGF? is a powerful lever that has the potential to yield therapeutic benefit in cases where bone homeostasis needs to be recalibrated. PMID:24404376

Tang, Simon Y; Alliston, Tamara

2013-01-01

280

Fruits and dietary phytochemicals in bone protection.  

PubMed

Osteoporosis is a disease of bone characterized by loss of bone matrix and deterioration of bone microstructure that leads to an increased risk of fracture. Cross-sectional studies have shown a positive association between higher fruit intake and higher bone mineral density. In this review, we evaluated animal and cellular studies of dried plum and citrus and berry fruits and bioactive compounds including lycopene, phenolics, favonoids, resveratrol, phloridzin, and pectin derived from tomato, grapes, apples, and citrus fruits. In addition, human studies of dried plum and lycopene were reviewed. Animal studies strongly suggest that commonly consumed antioxidant-rich fruits have a pronounced effect on bone, as shown by higher bone mass, trabecular bone volume, number, and thickness, and lower trabecular separation through enhancing bone formation and suppressing bone resorption, resulting in greater bone strength. Such osteoprotective effects seem to be mediated via antioxidant or anti-inflammatory pathways and their downstream signaling mechanisms, leading to osteoblast mineralization and osteoclast inactivation. In future studies, randomized controlled trials are warranted to extend the bone-protective activity of fruits and their bioactive compounds. Mechanistic studies are needed to differentiate the roles of phytochemicals and other constitutes in bone protection offered by the fruits. Advanced imaging technology will determine the effective doses of phytochemicals and their metabolites in improving bone mass, microarchitecture integrity, and bone strength, which is a critical step in translating the benefits of fruit consumption on osteoporosis into clinical data. PMID:23244535

Shen, Chwan-Li; von Bergen, Vera; Chyu, Ming-Chien; Jenkins, Marjorie R; Mo, Huanbiao; Chen, Chung-Hwan; Kwun, In-Sook

2012-12-01

281

Bone regeneration effects of human allogenous bone substitutes: a preliminary study  

PubMed Central

Purpose The purpose of this study was to compare the bone regeneration effects of cortical, cancellous, and cortico-cancellous human bone substitutes on calvarial defects of rabbits. Methods Four 8-mm diameter calvarial defects were created in each of nine New Zealand white rabbits. Freeze-dried cortical bone, freeze-dried cortico-cancellous bone, and demineralized bone matrix with freeze-dried cancellous bone were inserted into the defects, while the non-grafted defect was regarded as the control. After 4, 8, and 12 weeks of healing, the experimental animals were euthanized for specimen preparation. Micro-computed tomography (micro-CT) was performed to calculate the percent bone volume. After histological evaluation, histomorphometric analysis was performed to quantify new bone formation. Results In micro-CT evaluation, freeze-dried cortico-cancellous human bone showed the highest percent bone volume value among the experimental groups at week 4. At week 8 and week 12, freeze-dried cortical human bone showed the highest percent bone volume value among the experimental groups. In histologic evaluation, at week 4, freeze-dried cortico-cancellous human bone showed more prominent osteoid tissue than any other group. New bone formation was increased in all of the experimental groups at week 8 and 12. Histomorphometric data showed that freeze-dried cortico-cancellous human bone showed a significantly higher new bone formation percentile value than any other experimental group at week 4. At week 8, freeze-dried cortical human bone showed the highest value, of which a significant difference existed between freeze-dried cortical human bone and demineralized bone matrix with freeze-dried cancellous human bone. At week 12, there were no significant differences among the experimental groups. Conclusions Freeze-dried cortico-cancellous human bone showed swift new bone formation at the 4-week healing phase, whereas there was less difference in new bone formation among the experimental groups in the following healing phases. PMID:20607058

Lee, Deok-Won; Koo, Ki-Tae; Seol, Yang-Jo; Lee, Yong-Moo; Ku, Young; Rhyu, In-Chul; Chung, Chong-Pyoung

2010-01-01

282

Analysis of bone protein and mineral composition in bone disease using synchrotron infrared microspectroscopy  

NASA Astrophysics Data System (ADS)

Infrared (IR) microspectroscopy is an analytical technique that is highly sensitive to the chemical components in bone. The brightness of a synchrotron source permits the examination of individual regions of bone in situ at a spatial resolution superior to that of a conventional infrared source. At Beamlines U10B and U2B at the National Synchrotron Light Source, we are examining the role of bone chemical composition in bone disease. In osteoarthritis (OA), it has been demonstrated that the bone underlying the joint cartilage (subchondral bone) becomes thickened prior to cartilage breakdown. Using synchrotron infrared microspectroscopy, we have examined the chemical composition of the subchondral bone in histologically normal and OA monkeys. Results demonstrate that the subchondral bone of OA monkeys is significantly more mineralized than the normal bone, primarily due to an increase in carbonate concentration in the OA bone. High resolution analysis indicates that differences in carbonate content are uniform throughout the subchondral bone region, suggesting that high subchondral bone carbonate may be a marker for OA. Conversely, increases in phosphate content are more pronounced in the region near the marrow space, suggesting that, as the subchondral bone thickens, the bone also becomes more mineralized. Osteoporosis is a disease characterized by a reduction in bone mass and a skeleton that is more susceptible to fracture. To date, it is unclear whether bone remodeled after the onset of osteoporosis differs in chemical composition from older bone. Using fluorescence-assisted infrared microspectroscopy, we are comparing the composition of monkey bone remodeled at various time points after the onset of osteoporosis (induced by ovariectomy). We find that the chemical composition of bone remodeled one year after ovariectomy and one year prior to necropsy is similar to normal bone. On the other hand, bone remodeled two years after ovariectomy is less mature, indicated by lower mineral/protein ratios and higher acid phosphate content. This immature bone may also be a symptom of slower bone formation rates related to estrogen deficiency.

Miller, Lisa M.; Hamerman, David; Chance, Mark R.; Carlson, Cathy S.

1999-10-01

283

Autologous bone graft versus demineralized bone matrix in internal fixation of ununited long bones  

PubMed Central

Background Non-unions are severe complications in orthopaedic trauma care and occur in 10% of all fractures. The golden standard for the treatment of ununited fractures includes open reduction and internal fixation (ORIF) as well as augmentation with autologous-bone-grafting. However, there is morbidity associated with the bone-graft donor site and some patients offer limited quantity or quality of autologous-bone graft material. Since allogene bone-grafts are introduced on the market, this comparative study aims to evaluate healing characteristics of ununited bones treated with ORIF combined with either iliac-crest-autologous-bone-grafting (ICABG) or demineralized-bone-matrix (DBM). Methods and results From 2000 to 2006 out of sixty-two consecutive patients with non-unions presenting at our Level I Trauma Center, twenty patients had ununited diaphyseal fractures of long bones and were treated by ORIF combined either by ICABG- (n = 10) or DBM-augmentation (n = 10). At the time of index-operation, patients of the DBM-group had a higher level of comorbidity (ASA-value: p = 0.014). Mean duration of follow-up was 56.6 months (ICABG-group) and 41.2 months (DBM-group). All patients were clinically and radiographically assessed and adverse effects related to bone grafting were documented. The results showed that two non-unions augmented with ICABG failed osseous healing (20%) whereas all non-unions grafted by DBM showed successful consolidation during the first year after the index operation (p = 0.146). No early complications were documented in both groups but two patients of the ICABG-group suffered long-term problems at the donor site (20%) (p = 0.146). Pain intensity were comparable in both groups (p = 0.326). However, patients treated with DBM were more satisfied with the surgical procedure (p = 0.031). Conclusion With the use of DBM, the costs for augmentation of the non-union-site are more expensive compared to ICABG (calculated difference: 160 €/case). Nevertheless, this study demonstrated that the application of DBM compared to ICABG led to an advanced outcome in the treatment of non-unions and simultaneously to a decreased quantity of adverse effects. Therefore we conclude that DBM should be offered as an alternative to ICABG, in particular to patients with elevated comorbidity and those with limited availability or reduced quality of autologous-bone graft material. PMID:20003511

2009-01-01

284

Recent advances in bone tissue engineering scaffolds  

PubMed Central

Bone disorders are of significant concern due to increase in the median age of our population. Traditionally, bone grafts have been used to restore damaged bone. Synthetic biomaterials are now being used as bone graft substitutes. These biomaterials were initially selected for structural restoration based on their biomechanical properties. Later scaffolds were engineered to be bioactive or bioresorbable to enhance tissue growth. Now scaffolds are designed to induce bone formation and vascularization. These scaffolds are often porous, biodegradable materials that harbor different growth factors, drugs, genes or stem cells. In this review, we highlight recent advances in bone scaffolds and discuss aspects that still need to be improved. PMID:22939815

Bose, Susmita; Roy, Mangal; Bandyopadhyay, Amit

2012-01-01

285

Drug-induced bone loss.  

PubMed

Bone loss leading to osteoporosis is common after the menopause and in the elderly but uncommon in normal young adults without predisposing factors. The risk factors usually associated with osteoporosis include a family history of osteoporosis or fractures, aging, prior diseases, sedentary lifestyle, low calcium intake, hypogonadism, vitamin D deficiency, smoking, and excessive alcohol consumption. However, the issue of drugs has to be considered in 'normal' individuals who present with osteoporosis or bone loss without predisposing genetic or other environmental factors. The list of drugs is extensive and includes, amongst others, glucocorticoids, thyroid hormone (excess), alcohol, medroxyprogesterone acetate, luteinizing hormone-releasing hormone agonists, anti-seizure medications, cyclosporine A, aluminium, lithium, and exchange resins. This paper reviews the pathophysiology and mechanisms of drug-induced bone loss, which includes osteoporosis and osteomalacia, and treatment concepts. Undoubtedly, physician awareness, appropriate investigation, careful prescribing, monitoring, and proper therapy for this eminently preventable side effect can preserve bone in the patients receiving bone-losing drugs. PMID:11095167

Tannirandorn, P; Epstein, S

2000-01-01

286

[Interventional radiology for bone metastases].  

PubMed

The management of bone metastases requires a multidisciplinary staff to include systemic and local treatments like radiotherapy, surgery or interventional radiology (IR). Patients are often fragile. Imaging allows safe guidance to create "mini-invasive" procedures under adequate anesthesia. Patients' selection is important. If the goal is pain relief, cementoplasty provides a very effective bone consolidation and pain control. Simple and low-risk, vertebroplasty is the technique of choice in case of lytic bone metastases with spinal fracture risk or after failure of analgesic radiotherapy. If the medical project is curative, the tumor ablation procedures are realised through thermic or embolic techniques. After 60°C, the heat induces a coagulative necrose. Under -20°C, the cold leads to destroy the tissues. The major advantage of the cryotherapy is the predictibility of the ablation zone due to the well-visualized ice ball on perprocedural images. This technique is much more adapted to spare the nervous structures closed to the metastasis. The development of these new techniques of IR will treat bone metastases earlier, sometimes asymptomatic and thus improves the quality of life in patients with bone metastases. PMID:24153025

Iannessi, Antoine; Garnon, Julien; Cormier, Évelyne; Clarencon, Frédéric; Chiras, Jacques

2013-11-01

287

[Ultrasound and the bone: a difficult relationship].  

PubMed

The principles of US physics and technology hampering both the production of US images of the bone and the assessment of the soft tissue structures underlying it are discussed. In theory, two US parameters play a role in this field: the different transmission velocity of the US beam through soft tissues and bone, and the marked attenuation of the US beam when crossing the bone. The former parameter, due to higher density and lower compressibility of the bone with respect to soft tissues, causes both intense reflection (and thus beam weakening) and refraction (and thus lateral resolution and US image distortions) at the soft tissue/bone interfaces. Moreover, US transmission velocity in the bone differs significantly from the reference velocity of the US scanners on the market based on that of soft tissues. As a consequence, during the reconstruction of a bone US image, artifacts resulting in the axial compression of bone structures should, at least in theory, occur. The latter parameter, due to both conversion into heat (absorption) and local dispersion (scattering), is likely to be main factor causing the loss of US energy when the US beam passes through the bone. Although the amount of matter (bone mass or density) undoubtedly accounts for some attenuation, local bone architecture (bulk and shear moduli of bone and marrow, bone and marrow density, marrow viscosity and porosity, permeability and tortuosity of cancellous bone structure) seems nevertheless also responsible for some attenuation through both absorption and scattering. Other consequences of attenuation reflecting on US imaging of the bone are: marked lowering of central transducer frequency and US beam widening preventing the correct identification of the interfaces originating echoes by relating them to the structures on the transducer axis. In conclusion, based on the above parameters, echoencephalography and transcranial Doppler US can be expected to improve, in the near future, their bone-crossing capabilities, even though no true gray-scale bone sonogram will ever be feasible. PMID:7716291

Cittadini, G; Martinoli, C

1995-01-01

288

The response of bone to unloading  

NASA Technical Reports Server (NTRS)

Skeletal unloading leads to decreased bone formation and decreased bone mass. Bone resorption is uncoupled from bone formation, contributing to the bone loss. During spaceflight bone is lost principally from the bones most loaded in the 1-g environment, and some redistribution of bone from the lower extremities to the head appears to take place. Although changes in calcitropic hormones have been demonstrated during skeletal unloading (PTH and 1,25(OH)2D decrease), it remains unclear whether such changes account for or are in response to the changes in bone formation and resorption. Bed rest studies with human volunteers and hindlimb elevation studies with rats have provided useful data to help explain the changes in bone formation during spaceflight. These models of skeletal unloading reproduce a number of the conditions associated with microgravity, and the findings from such studies confirm many of the observations made during spaceflight. Determining the mechanism(s) by which loading of bone is sensed and translated into a signal(s) controlling bone formation remains the holy grail in this field. Such investigations couple biophysics to biochemistry to cell and molecular biology. Although studies with cell cultures have revealed biochemical responses to mechanical loads comparable to that seen in intact bone, it seems likely that matrix-cell interactions underlie much of the mechanocoupling. The role for systemic hormones such as PTH, GH, and 1,25(OH)2D compared to locally produced factors such as IGF-I, PTHrP, BMPs, and TGF-beta in modulating the cellular response to load remains unclear. As the mechanism(s) by which bone responds to mechanical load with increased bone formation are further elucidated, applications of this knowledge to other etiologies of osteoporosis are likely to develop. Skeletal unloading provides a perturbation in bone mineral homeostasis that can be used to understand the mechanisms by which bone mineral homeostasis is maintained, with the expectation that such understanding will lead to effective treatment for disuse osteoporosis.

Bikle, D. D.; Halloran, B. P.

1999-01-01

289

Bone banks and allografts in community practice.  

PubMed

The increasing volume of orthopaedic reconstructive procedures requiring replacement of bone stock justifies the initiation of programs of bone banking in community hospitals. Provided that strict criteria are followed to assure rigorous screening of donor bone and the reliable preservation of bone graft material, community banking is safe and cost-effective. Banked allograft bone can be used successfully in a wide variety of orthopaedic procedures performed in community hospitals. In general, the best uses are filling bone cavities, buttressing, and augmenting the quantity of autograft bone. In revision reconstructive surgery of the hip, bank bone is used to replace bone stock in protrusio, acetabular dysplasia, and proximal femoral deficiency. The best and most common indication for the use of bank bone in tumor surgery is after curettage or excision of benign lesions. Allografts may be used to reconstruct bony defects after excision of malignant tumors and in the surgical treatment of metastatic disease. These instances require larger bone bank facilities than those commonly available in a community hospital setting. Medicolegal considerations related to bone banking and the use of allografts in community practice include the regulatory requirements outlined in the UAGA, questions concerning negligence liability, and theories of strict product liability. Overall, good medical practice and obtaining informed consents will minimize legal risks related to bone banking and transplantation in a community setting. PMID:3047236

Czitrom, A A; Gross, A E; Langer, F; Sim, F H

1988-01-01

290

Bone Marrow Microenvironment and Tumor Progression  

PubMed Central

The bone marrow constitutes an unique microenvironment for cancer cells in three specific aspects. First, the bone marrow actively recruits circulating tumor cells where they find a sanctuary rich in growth factors and cytokines that promote their proliferation and survival. When in the bone marrow, tumor cells profoundly affect the homeostasis of the bone and the balance between osteogenesis and osteolysis. As a consequence, growth and survival factors normally sequestered into the bone matrix are released, further fueling cancer progression. Second, tumor cells actively recruit bone marrow-derived precursor cells into their own microenvironment. When in the tumors, these bone marrow-derived cells contribute to an inflammatory reaction and to the formation of the tumor vasculature. Third, bone marrow-derived cells can home in distant organs, where they form niches that attract circulating tumor cells. Our understanding of the contribution of the bone marrow microenvironment to cancer progression has therefore dramatically improved over the last few years. The importance of this new knowledge cannot be underestimated considering that the vast majority of cancer treatments such as cytotoxic and myeloablative chemotherapy, bone marrow transplantation and radiation therapy inflict a trauma to the bone marrow microenvironment. How such trauma affects the influence that the bone marrow microenvironment exerts on cancer is still poorly understood. In this article, the reciprocal relationship between the bone marrow microenvironment and tumor cells is reviewed, and its potential impact on cancer therapy is discussed. PMID:19308682

Chantrain, Christophe F.; Feron, Olivier; Marbaix, Etienne

2008-01-01

291

Where did bone come from?  

PubMed Central

Bone is specific to vertebrates, and originated as mineralization around the basal membrane of the throat or skin, giving rise to tooth-like structures and protective shields in animals with a soft cartilage-like endoskeleton. A combination of fossil anatomy and genetic information from modern species has improved our understanding of the evolution of bone. Thus, even in man, there are still similarities in the molecular regulation of skin appendages and bone. This article gives a brief overview of the major milestones in skeletal evolution. Some molecular machineries involving members of core genetic networks and their interactions are described in the context of both old theories and modern genetic approaches. PMID:21657973

2011-01-01

292

Radionuclide Therapy of Bone Metastases  

PubMed Central

The skeleton is a potential metastatic target of many malignant tumors. Up to 85% of prostate and breast cancer patients may develop bone metastases causing severe pain syndromes in many of them. In patients suffering from multilocular, mainly osteoblastic lesions and pain syndrome, radionuclide therapy is recommended for pain palliation. Low-energy beta-emitting radionuclides (153samarium-ethylenediaminetetrameth-ylenephosphonate (EDTMP) and 89strontium) deliver high radiation doses to bone metastases and micrometastases in the bone marrow, but only negligible doses to the hematopoietic marrow. The response rate regarding pain syndrome is about 75%; about 25% of the patients may even become pain free. The therapy is repeatable, depending on cell counts. Concomitant treatment with modern bisphosphonates does not interfere with the treatment effects. Clinical trials using a new, not yet approved nuclide (223Radium) and/or combinations of chemotherapy and radionuclides are aiming at a more curative approach. PMID:22740795

Fischer, Manfred; Kampen, Willm U.

2012-01-01

293

Digital Classroom Resources: Napier's Bones  

NSDL National Science Digital Library

The Mathematical Association of America has teamed up the National Science Foundation to create an online collection of digital classroom resources. One of their more recent creations is this multimedia feature that teaches students about Napier's Bones. Created by Michael Caulfield and Wayne Anderson of Gannon University, this feature will introduce students to the work of John Napier, a 16th century mathematician who created a procedure for multiplication using sticks or bones. In this presentation, visitors can watch a step-by-step demonstration of this technique and then also enter any two factors of up to six digits each in order to create their own animation of this method. It is a nice way to get students thinking about this rather intriguing way to multiply, and the site also contains several links to other sites about John Napier and his bones.

294

[Bone anchored hearing aids (BAHA)].  

PubMed

Bone anchored hearing aids (BAHA) achieve optimal acoustic coupling by means of direct bone conduction via an osseointegrated percutaneous titanium implant. Currently this system has a record of over 30 years of clinical application and reliability. Patients with bilateral hearing loss with air-bone gaps will benefit from bilateral BAHA fitting. Likewise, unilateral conductive hearing loss with normal hearing on the other side can be treated with a BAHA. New developments in this field include the BAHA Intenso and also novel implant systems, such as the Epiplating system by Medicon, the alpha system by Otomag and the OBC system by Otorix. Due to the advantages of the BAHA system (possibility of preoperative testing, simple surgery without the risk of inner ear damage, MRI compatibility, etc.), the BAHA will keep its important role in hearing rehabilitation even in the era of other partially and totally implantable hearing devices. PMID:19343390

Federspil, P A

2009-03-01

295

Bone alterations associated with HIV.  

PubMed

HIV infection and initiation of antiretroviral therapy (ART) have been consistently associated with decreased bone mineral density (BMD), with growing evidence linking HIV to an increased risk of fracture. This is especially concerning with the expanding number of older persons living with HIV. Interestingly, recent data suggest that HIV-infected children and youth fail to achieve peak BMD, possibly increasing their lifetime risk of fracture. Elucidating the causes of the bone changes in HIV-positive persons is challenging because of the multifactorial nature of bone disease in HIV, including contribution of the virus, immunosuppression, ART toxicity, and traditional osteoporosis risk factors, such as age, lower weight, tobacco, and alcohol use. Thus, practitioners must recognize the risk of low BMD and fractures and appropriately screen patients for osteoporosis if risk factors exist. If fractures do occur or elevated fracture risk is detected through screening, treatment with bisphosphonate medications appears safe and effective in the HIV+population. PMID:25064454

Warriner, Amy H; Mugavero, Michael; Overton, E Turner

2014-09-01

296

COPD, bone metabolism, and osteoporosis.  

PubMed

COPD and osteoporosis are strongly associated because of common risk factors such as age, smoking, and inactivity. In addition, COPD-related systemic inflammation, vitamin D deficiency, and the use of systemic corticosteroids enhance ongoing bone destruction. Osteoporosis, in turn, may cause fragility fractures, which further impair mobility and increase morbidity and mortality. Vertebral compression fractures and rib cage fractures in patients with COPD may also reduce pulmonary function or enhance exacerbations. Early prevention and treatment of osteoporosis in COPD is, therefore, important and should be based on integrated risk assessment tools such as FRAX, which take bone mineral density, history of fragility fractures, and population-specific clinical factors into account. As long as intervention studies focusing on the bone in COPD are lacking, a more rigorous application of existing treatment guidelines of osteoporosis in general is mandatory. PMID:21362651

Lehouck, An; Boonen, Steven; Decramer, Marc; Janssens, Wim

2011-03-01

297

Bone marrow: the workhorse organ.  

PubMed

Bone marrow accounts for 3% to 6% of body weight and is dispersed throughout bone. In a healthy adult, bone marrow produces approximately 500 billion new blood cells daily to maintain steady-state levels in the peripheral circulation. Its output is measured using the complete blood count (CBC), which is arguably the most frequently ordered laboratory test in the clinical milieu. Hematopoiesis starts with hematopoietic stem cells that differentiate and mature into any of the three different types of mature blood cells. A simple CBC can rule out, confirm, or direct attention to anemia, cancer, infection, acute hemorrhage states, toxin exposure, allergies, immunodeficiencies, or adverse drug reactions. Interpreting CBCs depends on reference values from the laboratory that processes the blood sample. Since reference intervals are formulated based on a younger, much healthier population, data specific to elderly people are limited. PMID:23315278

Wick, Jeannette Y

2013-01-01

298

A Comparison between Xenogenic Deproteinized Bone Substitute Pyrost ® and Autologous Bone Graft in the Surgical Management of Simple Bone Cysts  

Microsoft Academic Search

Background: The basic principle of surgical treatment of simple bone cysts has remained unchanged over the years, with curettage followed by packing of the defect with autogenic bone graft. With the introduction of ceramic biomaterials, an alternative packing material is available, avoiding the complications associated with cancellous bone harvesting or the use of a bioceramic implant. The aim of this

Lars Perlick; Oliver Diedrich; Holger Bäthis; Detlef Zander; Clayton N. Kraft

2001-01-01

299

Bone marrow: all the cells of the immune system are derived from stem cells in the bone marrow. The bone  

E-print Network

Bone marrow: all the cells of the immune system are derived from stem cells in the bone marrow. The bone marrow is the site of origin of red blood cells, white cells (including lymphocytes and macrophages) and platelets. Thymus: in the thymus gland lymphoid cells undergo a process of maturation

Morante, Silvia

300

Bone Mineral Density and Logarithms  

NSDL National Science Digital Library

Students examine an image produced by a cabinet x-ray system to determine if it is a quality bone mineral density image. They write in their journals about what they need to know to be able to make this judgment. Students learn about what bone mineral density is, how a BMD image can be obtained, and how it is related to the x-ray field. Students examine the process used to obtain a BMD image and how this process is related to mathematics, primarily through logarithmic functions. They study the relationship between logarithms and exponents, the properties of logarithms, common and natural logarithms, solving exponential equations and Beer's law.

Vu Bioengineering Ret Program

301

[Dental implantation by low-density bone].  

PubMed

The paper analyzes modern approaches to bone density evaluation by planning of dental implantation procedure. Implantation technique in patients with low-density bone creating favorable conditions for osseous integration is described. PMID:23268182

Kulakov, A A; Arkhipov, A V

2012-01-01

302

Planning for a Bone Marrow Transplant (BMT)  

MedlinePLUS

... Facebook Google Bookmarks Planning for a Bone Marrow Transplant (BMT) When a bone marrow transplant (also called ... Teenager Through His or Her Transplant Consider the Transplant Center You may want to have a discussion ...

303

21 CFR 892.1180 - Bone sonometer.  

Code of Federal Regulations, 2012 CFR

...RADIOLOGY DEVICES Diagnostic Devices § 892.1180 Bone sonometer...Identification . A bone sonometer is a device that transmits ultrasound...health and fracture risk. The primary components of the device are a voltage...

2012-04-01

304

21 CFR 892.1180 - Bone sonometer.  

Code of Federal Regulations, 2010 CFR

...RADIOLOGY DEVICES Diagnostic Devices § 892.1180 Bone sonometer...Identification . A bone sonometer is a device that transmits ultrasound...health and fracture risk. The primary components of the device are a voltage...

2010-04-01

305

Genetics Home Reference: Paget disease of bone  

MedlinePLUS

... It is most common in people of western European heritage. Early-onset Paget disease of bone is ... developing Paget disease of bone. Studies suggest that genetic variations in certain regions of chromosome 2, chromosome 5, ...

306

Processed bovine dentine as a bone substitute  

Microsoft Academic Search

ObjectivesDifferent forms of allogenic dentine have been studied for their potential use as bone substitutes. We report a new method for processing bovine dentine that results in a sterile bioactive material for repair and regeneration of bone.

Keyvan Moharamzadeh; Christine Freeman; Keith Blackwood

2008-01-01

307

Myeloma Bone Disease: Current and Future Treatment  

MedlinePLUS

... and immune cells present in the marrow. Furthermore, growth factors released from the process of bone destruction also ... of myeloma cells. This creates a vicious cycle: Growth factors are released, as bone is destroyed. This leads ...

308

Bone Mass and Bone Metabolism Markers during Adolescence: The HELENA Study  

Microsoft Academic Search

Background\\/Aims: The assessment of bone mineral content (BMC) and density (BMD) status in children and adolescents is important for health and the prevention of diseases. Bone metabolic activity could provide early information on bone mass development. Our aim was to describe bone mass and metabolism markers according to age and Tanner stage in adolescents. Methods: Spanish adolescents (n = 345;

L. Gracia-Marco; G. Vicente-Rodríguez; J. Valtueña; J. P. Rey-López; A. E. Díaz Martínez; M. I. Mesana; K. Widhalm; J. R. Ruiz; M. González-Gross; M. J. Castillo; L. A. Moreno

2010-01-01

309

Bone quality: A determinant for certain risk factors for bone fragility  

Microsoft Academic Search

Summary Low bone quantity alone is insufficient cause for fragility fractures. This paper examines the role of bone quality in the fracture risk associated with age, sex, and race. Aspects of bone quality to be considered are bone architecture, matrix, mineralization, and fatigue damage. The trabecular network becomes progressively disconnected and weaker with age. Death of old osteocytes leads to

Christine M. Schnitzler

1993-01-01

310

Affinity of bone sialoprotein and several other bone and dentin acidic proteins to collagen fibrils  

Microsoft Academic Search

Summary Bone and dentin contain several kinds of mineral-binding proteins and cell-attachment proteins. The authors examined the affinity of these proteins to type I collagen, a major matrix protein of the tissue. Bone sialoprotein (BSP), bone Gla protein (BGP), bone small proteoglycan II (PG II), osteonectin (ON), and dentin phosphophoryn (DPP) were labeled with fluorescein isothiocyanate and incubated with reconstituted

K. Fujisawa; Y. Kuboki

1992-01-01

311

Bone Marrow Microenvironment and Tumor Progression  

Microsoft Academic Search

The bone marrow constitutes an unique microenvironment for cancer cells in three specific aspects. First, the bone marrow\\u000a actively recruits circulating tumor cells where they find a sanctuary rich in growth factors and cytokines that promote their\\u000a proliferation and survival. When in the bone marrow, tumor cells profoundly affect the homeostasis of the bone and the balance\\u000a between osteogenesis and

Christophe F. Chantrain; Olivier Feron; Etienne Marbaix; Yves A. DeClerck

2008-01-01

312

Gravity, calcium, and bone - Update, 1989  

NASA Technical Reports Server (NTRS)

Recent results obtained on skeletal adaptation, calcium metabolism, and bone browth during short-term flights and ground simulated-microgravity experiments are presented. Results demonstrate that two principal components of calcium metabolism respond within days to changes in body position and to weightlessness: the calcium endocrine system and bone characteristics. Furthermore, results of recent studies imply that bone biomechanics are more severely affected by spaceflight exposures than is the bone mass.

Arnaud, Sara B.; Morey-Holton, Emily

1990-01-01

313

Regenerate augmentation with bone marrow concentrate after traumatic bone loss.  

PubMed

Distraction osteogenesis after post-traumatic segmental bone loss of the tibia is a complex and time-consuming procedure that is often complicated due to prolonged consolidation or complete insufficiency of the regenerate. The aim of this feasibility study was to investigate the potential of bone marrow aspiration concentrate (BMAC) for percutaneous regenerate augmentation to accelerate bony consolidation of the regenerate. Eight patients (age 22-64) with an average posttraumatic bone defect of 82.4 mm and concomitant risk factors (nicotine abuse, soft-tissue defects, obesity and/or circulatory disorders) were treated with a modified Ilizarov external frame using an intramedullary cable transportation system. At the end of the distraction phase, each patient was treated with a percutaneously injection of autologous BMAC into the centre of the regenerate. The concentration factor was analysed using flow cytometry. The mean follow up after frame removal was 10 (4-15) months. With a mean healing index (HI) of 36.9 d/cm, bony consolidation of the regenerate was achieved in all eight cases. The mean concentration factor of the bone marrow aspirate was 4.6 (SD 1.23). No further operations concerning the regenerate were needed and no adverse effects were observed with the BMAC procedure. This procedure can be used for augmentation of the regenerate in cases of segmental bone transport. Further studies with a larger number of patients and control groups are needed to evaluate a possible higher success rate and accelerating effects on regenerate healing. PMID:22577502

Gessmann, Jan; Köller, Manfred; Godry, Holger; Schildhauer, Thomas Armin; Seybold, Dominik

2012-01-01

314

BoneJ: free and extensible bone image analysis in ImageJ  

PubMed Central

Bone geometry is commonly measured on computed tomographic (CT) and X-ray microtomographic (?CT) images. We obtained hundreds of CT, ?CT and synchrotron ?CT images of bones from diverse species that needed to be analysed remote from scanning hardware, but found that available software solutions were expensive, inflexible or methodologically opaque. We implemented standard bone measurements in a novel ImageJ plugin, BoneJ, with which we analysed trabecular bone, whole bones and osteocyte lacunae. BoneJ is open source and free for anyone to download, use, modify and distribute. PMID:20817052

Doube, Michael; K?osowski, Micha? M; Arganda-Carreras, Ignacio; Cordelières, Fabrice P; Dougherty, Robert P; Jackson, Jonathan S; Schmid, Benjamin; Hutchinson, John R; Shefelbine, Sandra J

2011-01-01

315

Effects of Inactivity and Exercise on Bone.  

ERIC Educational Resources Information Center

Research has shown that bone tissue responds to the forces of gravity and muscle contraction. The benefits of weight-bearing exercise in preventing or reversing bone mass loss related to osteoporosis is reviewed. The effects of weightlessness and immobilization, and the possible effects of athletic amenorrhea, on bone mineral density are…

Smith, Everett L.; Gilligan, Catherine

1987-01-01

316

Hormonal and Local Regulation of Bone Formation.  

ERIC Educational Resources Information Center

Reviews effects of hormones, systemic factors, and local regulators on bone formation. Identifies and explains the impact on bone growth of several hormones as well as the components of systemic and local systems. Concentrates on bone collagen and DNA synthesis. (Physicians may earn continuing education credit by completing an appended test). (ML)

Canalis, Ernesto

1985-01-01

317

Bone marrow and the control of immunity  

Microsoft Academic Search

Bone marrow is thought to be a primary hematopoietic organ. However, accumulated evidences demonstrate that active function and trafficking of immune cells, including regulatory T cells, conventional T cells, B cells, dendritic cells, natural killer T (NKT) cells, neutrophils, myeloid-derived suppressor cells and mesenchymal stem cells, are observed in the bone marrow. Furthermore, bone marrow is a predetermined metastatic location

Ende Zhao; Huanbin Xu; Lin Wang; Ilona Kryczek; Ke Wu; Yu Hu; Guobin Wang; Weiping Zou

2012-01-01

318

Cell Stem Cell Endogenous Bone Marrow MSCs  

E-print Network

). The existence of multipotent bone marrow stromal cells (BMSCs), or skeletal/mesenchymal stem cells (SSCs of cultured cells (Sacchetti et al., 2007). Similar multipotent MSCs can be isolated from mouse bone marrowCell Stem Cell Article Endogenous Bone Marrow MSCs Are Dynamic, Fate-Restricted Participants

Mootha, Vamsi K.

319

Engineering Polymeric Scaffolds for Bone Grafts  

Microsoft Academic Search

Orthopedic injuries resulting from trauma or improper development often require surgical intervention to restore natural tissue function. Currently, over one million operations are performed annually for the surgical reconstruction of bone [50]. The well-known limitations associated with autografts, allografts, and bone cements have led to the investigation of synthetic polymers as support matrices for bone tissue engineering. Polymers are long-chain

Martha W. Betz; Diana M. Yoon; John P. Fisher

320

Bone invasion in secondary syphilis: case reports.  

PubMed Central

The affinity of treponemes for bone tissue is well known, but the incidence of bone infection in the early stages of syphilis is uncertain. Although case reports of early bone invasion are few, reviews of large numbers of patients with early syphilis indicate that the incidence is probably greater than at present believed. Two case reports are presented. Images PMID:3410468

Ollé-Goig, J E; Barrio, J L; Gurgui, M; Mildvan, D

1988-01-01

321

Biomaterial developments for bone tissue engineering  

Microsoft Academic Search

The development of bone tissue engineering is directly related to changes in materials technology. While the inclusion of materials requirements is standard in the design process of engineered bone substitutes, it is also critical to incorporate clinical requirements in order to engineer a clinically relevant device. This review presents the clinical need for bone tissue-engineered alternatives to the present materials

Karen J. L Burg; Scott Porter; James F Kellam

2000-01-01

322

Vascular Calcification and Renal Bone Disorders  

PubMed Central

At the early stage of chronic kidney disease (CKD), the systemic mineral metabolism and bone composition start to change. This alteration is known as chronic kidney disease-mineral bone disorder (CKD-MBD). It is well known that the bone turnover disorder is the most common complication of CKD-MBD. Besides, CKD patients usually suffer from vascular calcification (VC), which is highly associated with mortality. Many factors regulate the VC mechanism, which include imbalances in serum calcium and phosphate, systemic inflammation, RANK/RANKL/OPG triad, aldosterone, microRNAs, osteogenic transdifferentiation, and effects of vitamins. These factors have roles in both promoting and inhibiting VC. Patients with CKD usually have bone turnover problems. Patients with high bone turnover have increase of calcium and phosphate release from the bone. By contrast, when bone turnover is low, serum calcium and phosphate levels are frequently maintained at high levels because the reservoir functions of bone decrease. Both of these conditions will increase the possibility of VC. In addition, the calcified vessel may secrete FGF23 and Wnt inhibitors such as sclerostin, DKK-1, and secreted frizzled-related protein to prevent further VC. However, all of them may fight back the inhibition of bone formation resulting in fragile bone. There are several ways to treat VC depending on the bone turnover status of the individual. The main goals of therapy are to maintain normal bone turnover and protect against VC. PMID:25136676

Lu, Kuo-Cheng; Wu, Chia-Chao; Yen, Jen-Fen; Liu, Wen-Chih

2014-01-01

323

Vibrational spectroscopy in biomedical science: bone  

NASA Astrophysics Data System (ADS)

Fourier transform infrared imaging (FTIR) and Raman Microspectroscopy are powerful tools for characterizing the distribution of different chemical moieties in heterogeneous materials. FTIR and Raman measurements have been adapted to assess the maturity of the mineral and the quality of the organic component (collagen and non-collagenous proteins) of the mineralized tissue in bone. Unique to the FTIRI analysis is the capability to provide the spatial distribution of two of the major collagen cross-links (pyridinoline, and dehydro-dihydroxylysinonorleucine) and through the study of normal and diseased bone, relate them to bone strength. These FTIR parameters have been validated based on analysis of model compounds. It is widely accepted that bone strength is determined by bone mass and bone quality. The latter is a multifactorial term encompassing the material and structural properties of bone, and one important aspect of the bone material properties is the organic matrix. The bone material properties can be defined by parameters of mineral and collagen, as determined by FTIR and Raman analysis. Considerably less attention has been directed at collagen, although there are several publications in the literature reporting altered collagen properties associated with fragile bone, in both animals and humans. Since bone is a heterogeneous tissue due to the remodeling process, microscopic areas may be carefully selected based on quantitative Backscattered Electron Imaging or histological staining, thus ensuring comparison of areas with similar metabolic activity and mineral content. In conclusion, FTIRI and Raman vibrational spectroscopy are proving to be powerful tools in bone-related medical research.

Gamsjäger, Sonja; Zoehrer, R.; Roschger, P.; Fratzl, P.; Klaushofer, K.; Mendelsohn, R.; Paschalis, E. P.

2009-02-01

324

Radionuclide bone images in hypertrophic pulmonary osteoarthropathy.  

PubMed

Hypertrophic Pulmonary Osteoarthropathy (HPO) can be differentiated from osseous metastasis on conventional bone images using technetium 99m radiopharmaceuticals. Periosteal new bone formation appears as symmetric circumferential deposition of radionuclide in the diaphyseal cortex of tubular bones. In contrast, asymmetrical deposits in the medullary canal are indicative of metastatic disease. The etiologies of hypertrophic osteoarthropathy are discussed. PMID:1163719

Terry, D W; Isitman, A T; Holmes, R A

1975-08-01

325

Automated decision support for bone scintigraphy  

Microsoft Academic Search

A quantitative analysis of metastatic bone involvement can be an important prognostic indicator of survival or a tool in monitoring treatment response in patients with cancer. The purpose of this study was to develop a completely automated decision support system for whole-body bone scans using image analysis and artificial neural networks. The study population consisted of 795 whole-body bone scans.

Mattias Ohlsson; Reza Kaboteh; May Sadik; Madis Suurkula; Milan Lomsky; Peter Gjertsson; Karl Sjöstrand; Jens Richter; Lars Edenbrandt

2009-01-01

326

Femoral neck bone density and fracture risk  

Microsoft Academic Search

Osteoporosis is a skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture. The disorder is a major health problem through its relationship with these fractures, which typically occur at three skeletal sites: the hip, wrist and spine (1). It has been estimated from incidence rates

C. Cooper; Epidemiology Unit

1996-01-01

327

The family of bone morphogenetic proteins  

Microsoft Academic Search

The family of bone morphogenetic proteins. Bone morphogenetic proteins (BMPs) are secreted signaling molecules belonging to the transforming growth factor-? (TGF-?) superfamily of growth factors. The first BMPs were originally identified by their ability to induce ectopic bone formation when implanted under the skin of rodents. In this ectopic overexpression assay, there was a recapitulation of all the events occurring

Patricia Ducy; Gerard Karsenty

2000-01-01

328

Bone-Conduction ABR Tests.  

ERIC Educational Resources Information Center

This article discusses the accuracy of bone-conduction auditory brainstem response (BC-ABR) tests to determine the presence and severity of conductive hearing impairment. It provides warnings about technical pitfalls and recommends incorporating BC-ABR protocols for routine clinical use. It concludes that the method allows estimating cochlear…

Cone-Wesson, Barbara

1995-01-01

329

Bone weighs in on obesity.  

PubMed

Obesity, insulin resistance, and diabetes are related disorders of energy metabolism for which therapies are suboptimal. In this issue of Cell, Lee et al. (2007) demonstrate in mice that bone regulates the insulin/glucose axis and energy metabolism, providing a new framework for approaching common disorders of bioenergetics. PMID:17693252

Semenkovich, Clay F; Teitelbaum, Steven L

2007-08-10

330

Biomodels of Bone: A Review  

Microsoft Academic Search

In this paper, a definition of a biomodel is presented, based on which different specific types of biomodels are identified, viz., virtual biomodels, computational biomodels, and physical biomodels. The paper then focuses on both physical and virtual biomodels of bone, and presents a review of model generation methodologies, giving examples of typical biomodel applications. The use of macroscale biomodels for

S. Lohfeld; V. Barron; P. E. McHugh

2005-01-01

331

Vegetarian diets and bone status.  

PubMed

Osteoporosis is a common chronic condition associated with progressive loss of bone mineral density (BMD) and compromised bone strength, with increasing risk of fracture over time. Vegetarian diets have been shown to contain lower amounts of calcium, vitamin D, vitamin B-12, protein, and n-3 (?-3) fatty acids, all of which have important roles in maintaining bone health. Although zinc intakes are not necessarily lower quantitatively, they are considerably less bioavailable in vegetarian diets, which suggests the need for even higher intakes to maintain adequate status. At the same time, healthy vegetarian diets tend to contain more of several protective nutrients, including magnesium, potassium, vitamin K, and antioxidant and anti-inflammatory phytonutrients. On balance, there is evidence that vegetarians, and particularly vegans, may be at greater risk of lower BMD and fracture. Attention to potential shortfall nutrients through the careful selection of foods or fortified foods or the use of supplements can help ensure healthy bone status to reduce fracture risk in individuals who adhere to vegetarian diets. PMID:24898237

Tucker, Katherine L

2014-06-01

332

Bone Mineralization in Celiac Disease  

PubMed Central

Evidence indicates a well-established relationship between low bone mineral density (BMD) and celiac disease (CD), but data on the pathogenesis of bone derangement in this setting are still inconclusive. In patients with symptomatic CD, low BMD appears to be directly related to the intestinal malabsorption. Adherence to a strict gluten-free diet (GFD) will reverse the histological changes in the intestine and also the biochemical evidence of calcium malabsorption, resulting in rapid increase of BMD. Nevertheless, GFD improves BMD but does not normalize it in all patients, even after the recovery of intestinal mucosa. Other mechanisms of bone injury than calcium and vitamin D malabsorption are thought to be involved, such as proinflammatory cytokines, parathyroid function abnormalities, and misbalanced bone remodeling factors, most of all represented by the receptor activator of nuclear factor B/receptor activator of nuclear factor B-ligand/osteoprotegerin system. By means of dual-energy X-ray absorptiometry (DXA), it is now rapid and easy to obtain semiquantitative values of BMD. However, the question is still open about who and when submit to DXA evaluation in CD, in order to estimate risk of fractures. Furthermore, additional information on the role of nutritional supplements and alternative therapies is needed. PMID:22737164

Larussa, Tiziana; Suraci, Evelina; Nazionale, Immacolata; Abenavoli, Ludovico; Imeneo, Maria; Luzza, Francesco

2012-01-01

333

Bone mineralization in celiac disease.  

PubMed

Evidence indicates a well-established relationship between low bone mineral density (BMD) and celiac disease (CD), but data on the pathogenesis of bone derangement in this setting are still inconclusive. In patients with symptomatic CD, low BMD appears to be directly related to the intestinal malabsorption. Adherence to a strict gluten-free diet (GFD) will reverse the histological changes in the intestine and also the biochemical evidence of calcium malabsorption, resulting in rapid increase of BMD. Nevertheless, GFD improves BMD but does not normalize it in all patients, even after the recovery of intestinal mucosa. Other mechanisms of bone injury than calcium and vitamin D malabsorption are thought to be involved, such as proinflammatory cytokines, parathyroid function abnormalities, and misbalanced bone remodeling factors, most of all represented by the receptor activator of nuclear factor B/receptor activator of nuclear factor B-ligand/osteoprotegerin system. By means of dual-energy X-ray absorptiometry (DXA), it is now rapid and easy to obtain semiquantitative values of BMD. However, the question is still open about who and when submit to DXA evaluation in CD, in order to estimate risk of fractures. Furthermore, additional information on the role of nutritional supplements and alternative therapies is needed. PMID:22737164

Larussa, Tiziana; Suraci, Evelina; Nazionale, Immacolata; Abenavoli, Ludovico; Imeneo, Maria; Luzza, Francesco

2012-01-01

334

Bone and soft tissue ablation.  

PubMed

Bone and soft tissue tumor ablation has reached widespread acceptance in the locoregional treatment of various benign and malignant musculoskeletal (MSK) lesions. Many principles of ablation learned elsewhere in the body are easily adapted to the MSK system, particularly the various technical aspects of probe/antenna design, tumoricidal effects, selection of image guidance, and methods to reduce complications. Despite the common use of thermal and chemical ablation procedures in bone and soft tissues, there are few large clinical series that show longitudinal benefit and cost-effectiveness compared with conventional methods, namely, surgery, external beam radiation, and chemotherapy. Percutaneous radiofrequency ablation of osteoid osteomas has been evaluated the most and is considered a first-line treatment choice for many lesions. Palliation of painful metastatic bone disease with thermal ablation is considered safe and has been shown to reduce pain and analgesic use while improving quality of life for cancer patients. Procedure-related complications are rare and are typically easily managed. Similar to all interventional procedures, bone and soft tissue lesions require an integrated approach to disease management to determine the optimum type of and timing for ablation techniques within the context of the patient care plan. PMID:25053865

Foster, Ryan C B; Stavas, Joseph M

2014-06-01

335

Bare Bones of Bioactive Glass  

NASA Technical Reports Server (NTRS)

Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

2000-01-01

336

Flavonoid intake and bone health  

Technology Transfer Automated Retrieval System (TEKTRAN)

Flavonoids, found in a wide diversity of plant foods, from fruits and vegetables, herbs and spices, essential oils, and beverages, have the most potential of dietary components for promotion of bone health beyond calcium and vitamin D. Recent epidemiological studies show flavonoid consumption to ha...

337

Special stem cells for bone.  

PubMed

Mesenchymal stem cells (MSCs) are multipotential in vitro, but their endogenous properties are poorly defined. In this issue of Cell Stem Cell, Park et al. (2012) report that an MSC-like, osteolineage-directed Mx1+ population generates new osteoblasts at sites of bone damage, suggesting its potential for skeletal repair and regeneration. PMID:22385649

Zaidi, Mone; Sun, Li; Blair, Harry C

2012-03-01

338

Bone Marrow Aspiration and Biopsy  

MedlinePLUS

... Deficiency , Hemoglobin Abnormalities , Bleeding Disorders Elsewhere On The Web College of American Pathologists: MyBiopsy.org American Society of Hematology: Blood Basics National Heart, Lung and Blood Institute: What are bone marrow tests? National Heart, Lung and Blood Institute: Blood Diseases ...

339

Bone metabolism after bariatric surgery.  

PubMed

Bariatric surgery is a popular and effective treatment for severe obesity but may have negative effects on the skeleton. This review summarizes changes in bone density and bone metabolism from animal and clinical studies of bariatric surgery, with specific attention to Roux-en-Y gastric bypass (RYGB), adjustable gastric banding (AGB), and sleeve gastrectomy (SG). Skeletal imaging artifacts from obesity and weight loss are also considered. Despite challenges in bone density imaging, the preponderance of evidence suggests that bariatric surgery procedures have negative skeletal effects that persist beyond the first year of surgery, and that these effects vary by surgical type. The long-term clinical implications and current clinical recommendations are presented. Further study is required to determine mechanisms of bone loss after bariatric surgery. Although early studies focused on calcium/vitamin D metabolism and mechanical unloading of the skeleton, it seems likely that surgically induced changes in the hormonal and metabolic profile may be responsible for the skeletal phenotypes observed after bariatric surgery. PMID:24677277

Yu, Elaine W

2014-07-01

340

Effect of strontium-containing hydroxyapatite bone cement on bone remodeling following hip replacement  

Microsoft Academic Search

It is uncertain whether the use of bioactive bone cement has any beneficial effect on local bone adaptation following hip\\u000a replacement. In this study, twelve goats underwent cemented hip hemiarthroplasty unilaterally, with either PMMA bone cement\\u000a or strontium-containing hydroxyapatite (Sr-HA) bioactive bone cement. Nine months later, the femoral cortical bones at different\\u000a levels were analyzed by microhardness testing and micro-CT

Guo X. Ni; Jian H. Lin; Peter K. Y. Chiu; Zhao Y. Li; William W. Lu

2010-01-01

341

A decade of bisphosphonate bone complications: what it has taught us about bone physiology.  

PubMed

While the AIDS epidemic of the 1980s taught the medical and dental professions much about immune cells and the immune system's cellular relationships, the bisphosphonate-induced osteonecrosis epidemic of the past decade has taught these same professions much about bone turnover, bone cell cross talk, the response and functional relationship of bone cells to loading, and drug effects on cellular dynamic relationships. The present article explores the literature as well as both evidence- and experience-based data to discuss known bone pathologies and physiologic mechanisms as well as uncover new findings: (1) bone remodeling is the mechanism by which bone adapts to loading stresses, termed either bone modeling or Wolff's law, and it is also the mechanism for bone renewal; (2) osteoclastic bone resorption triggers bone renewal at a rate of about 0.7%/day by its release of growth factors; (3) bisphosphonates prevent the renewal of old and injured bone, thus making it brittle and more likely to fracture over time; (4) bisphosphonates have a half-life in bone of 11 years because of their irreversible binding to bone via their central carbon atom; (5) when administered intravenously, bisphosphonate loads bone and accumulates in bone 142.8 times faster than when administered orally; (6) osteoclastic resorption of bisphosphonate-loaded bone results in osteoclast death in which the cell bursts, releasing the bisphosphonate molecules to reenter the local bone or bone marrow in a re-dosing effect; (7) endosteal osteoblasts are dependent on the osteoclastic resorption/growth factor release/new bone formation mechanism of bone renewal, whereas periosteal osteoblasts are not; and (8) it is likely that endosteal osteoblasts and periosteal osteoblasts have different cell membrane receptors and arise from separate embryologic niches. PMID:24683588

Marx, Robert E

2014-01-01

342

Craniofacial Bone Grafting: Wolff's Law Revisited  

PubMed Central

Bone grafts are used for the reconstruction of congenital and acquired deformities of the facial skeleton and, as such, comprise a vital component of the craniofacial surgeon's armamentarium. A thorough understanding of bone graft physiology and the factors that affect graft behavior is therefore essential in developing a more intelligent use of bone grafts in clinical practice. This article presents a review of the basic physiology of bone grafting along with a survey of pertinent concepts and current research. The factors responsible for bone graft survival are emphasized. PMID:22110789

Oppenheimer, Adam J.; Tong, Lawrence; Buchman, Steven R.

2008-01-01

343

Holographic measurements of fresh dry bone elasticity  

NASA Astrophysics Data System (ADS)

To compare the elasticity of bones covered with soft tissue and the elasticity of defleshed and dried bones, we used sampling screws to make the surface movements of the bones visible through the soft tissue. We compared fresh and dry European moose skulls before and after skinning. External forces were focused on the skull bones through the pedicles. A high correlation in fringe orientation was observed in the case of thick bone structures with rigid interdigited sutures. We also compared compression dynamics of fresh and dry moose antler cubes.

Silvennoinen, Raimo; Nygren, Kaarlo; Karna, Markku; Karna, Kari

1992-08-01

344

Cemented cup stability during lever-out testing after acetabular bone impaction grafting with bone graft substitutes mixes containing morselized cancellous bone and tricalcium phosphate--hydroxyapatite granules  

Microsoft Academic Search

Bone defects after failed total hip arthroplasty can be reconstructed with impacted morselized bone grafts and a cemented cup. In the near future the amount of bone grafts available for surgical purposes will be insufficient. Ceramic calcium phosphates [tricalcium phosphate (TCP) and hydroxyapatite (HA)] have been widely considered as potential bone graft substitutes or bone graft extenders. In the past,

J. J. C. Arts; B. W. Schreurs; P. Buma; N. J. J. Verdonschot

2005-01-01

345

Drilling of bone: A comprehensive review  

PubMed Central

Background Bone fracture treatment usually involves restoring of the fractured parts to their initial position and immobilizing them until the healing takes place. Drilling of bone is common to produce hole for screw insertion to fix the fractured parts for immobilization. Orthopaedic drilling during surgical process causes increase in the bone temperature and forces which can cause osteonecrosis reducing the stability and strength of the fixation. Methods A comprehensive review of all the relevant investigations carried on bone drilling is conducted. The experimental method used, results obtained and the conclusions made by the various researchers are described and compared. Result Review suggests that the further improvement in the area of bone drilling is possible. The systematic review identified several consequential factors (drilling parameters and drill specifications) affecting bone drilling on which there no general agreement among investigators or are not adequately evaluated. These factors are highlighted and use of more advanced methods of drilling is accentuated. The use of more precise experimental set up which resembles the actual situation and the development of automated bone drilling system to minimize human error is addressed. Conclusion In this review, an attempt has been made to systematically organize the research investigations conducted on bone drilling. Methods of treatment of bone fracture, studies on the determination of the threshold for thermal osteonecrosis, studies on the parameters influencing bone drilling and methods of the temperature measurement used are reviewed and the future work for the further improvement of bone drilling process is highlighted.

Pandey, Rupesh Kumar; Panda, S.S.

2013-01-01

346

Novel bone-targeted strategies in oncology.  

PubMed

Most patients with bone metastases experience skeletal complications, resulting in significant morbidity and increased risk of death. Although the use of bisphosphonates is a well-established form of supportive care treatment for bone metastasis, complications arising from long-term use require schedule optimization and a search for alternative strategies. Moreover, the scope of use of bone-targeted agents in oncology has widened to include therapy-induced bone loss and antitumor effects. Indeed, bone provides a permissive niche to tumor growth, and targeting the interactions within the bone microenvironment is a promising antitumor strategy. In addition, the pathogenesis of cancer-related bone disease has been partially unraveled with a focus on the anabolic bone compartment, and the rapid bench-to-bedside translation has resulted in the identification of novel therapeutically amenable targets. This review focuses on studies optimizing bisphosphonate use and recent clinical data on denosumab in the treatment of bone disease. We also provide data on trials that have evaluated the antitumor effects of bisphosphonates and summarize the most recent discoveries on the role of the bone niche in cancer development, with insights into the preclinical rationale and clinical assessment of novel antiresorptive and anabolic bone-targeted agents. PMID:20643782

Vallet, Sonia; Smith, Matthew R; Raje, Noopur

2010-08-15

347

NMR assessment on bone simulated under microgravity  

NASA Astrophysics Data System (ADS)

Introduction Microgravity-induced bone loss has been suggested to be similar to disuse-osteoporosis on Earth which constitutes a challenging public health problem No current non-destructive method can provide the microstructural changes in bone particularly on cortical bone Recently the authors have applied low field nuclear magnetic resonance NMR spin-spin relaxation technique and computational analysis method to determine the porosity pore size distribution and microdamage of cortical bone 1-3 The studies by the authors have shown that this technology can be used to characterize microstructural changes as well as bone water distribution bound and mobile water changes of weightless treated simulating a microgravity condition turkey and mouse cortical bone We further determinate that the NMR spin-spin relaxation time T 2 spectrum derived parameters can be used as descriptions of bone quality e g matrix water distribution and porosity size distributions and alone or in combination with current techniques bone mineral density measurements more accurately predict bone mechanical properties Methods underline Bone sample preparation Two kinds of animal samples were collected and prepared for designed experiments from SUNY Cortical bones of the mid-diaphyses of the ulnae of 1-year-old male turkeys were dissected from freshly slaughtered animals Eight samples were categorized from normal or control and four samples were 4-week disuse treated by functionally isolated osteotomies disuse A total of 12

Ni, Q.; Qin, Y.

348

Bone Remodelling Markers in Rheumatoid Arthritis  

PubMed Central

Bone loss in rheumatoid arthritis (RA) patients results from chronic inflammation and can lead to osteoporosis and fractures. A few bone remodeling markers have been studied in RA witnessing bone formation (osteocalcin), serum aminoterminal propeptide of type I collagen (PINP), serum carboxyterminal propeptide of type I collagen (ICTP), bone alkaline phosphatase (BAP), osteocalcin (OC), and bone resorption: C-terminal telopeptide of type 1 collagen (I-CTX), N-terminal telopeptide of type 1 collagen (I-NTX), pyridinolines (DPD and PYD), and tartrate-resistant acid phosphatase (TRAP). Bone resorption can be seen either in periarticular bone (demineralization and erosion) or in the total skeleton (osteoporosis). Whatever the location, bone resorption results from activation of osteoclasts when the ratio between osteoprotegerin and receptor activator of nuclear factor kappa-B ligand (OPG/RANKL) is decreased under influence of various proinflammatory cytokines. Bone remodeling markers also allow physicians to evaluate the effect of drugs used in RA like biologic agents, which reduce inflammation and exert a protecting effect on bone. We will discuss in this review changes in bone markers remodeling in patients with RA treated with biologics. PMID:24839355

Fardellone, Patrice; Séjourné, Alice; Paccou, Julien; Goëb, Vincent

2014-01-01

349

Engineering Endochondral Bone: In Vivo Studies  

PubMed Central

The use of biomaterials to replace lost bone has been a common practice for decades. More recently, the demands for bone repair and regeneration have pushed research into the use of cultured cells and growth factors in association with these materials. Here we report a novel approach to engineer new bone using a transient cartilage scaffold to induce endochondral ossification. Chondrocyte/chitosan scaffolds (both a transient cartilage scaffold—experimental—and a permanent cartilage scaffold—control) were prepared and implanted subcutaneously in nude mice. Bone formation was evaluated over a period of 5 months. Mineralization was assessed by Faxitron, micro computed tomography, backscatter electrons, and Fourier transform infrared spectroscopy analyses. Histological analysis provided further information on tissue changes in and around the implanted scaffolds. The deposition of ectopic bone was detected in the surface of the experimental implants as early as 1 month after implantation. After 3 months, bone trabeculae and bone marrow cavities were formed inside the scaffolds. The bone deposited was similar to the bone of the mice vertebra. Interestingly, no bone formation was observed in control implants. In conclusion, an engineered transient cartilage template carries all the signals necessary to induce endochondral bone formation in vivo. PMID:18759673

Oliveira, Serafim M.; Mijares, Dindo Q.; Turner, Gloria; Amaral, Isabel F.; Barbosa, Mário A.

2009-01-01

350

Engineering endochondral bone: in vivo studies.  

PubMed

The use of biomaterials to replace lost bone has been a common practice for decades. More recently, the demands for bone repair and regeneration have pushed research into the use of cultured cells and growth factors in association with these materials. Here we report a novel approach to engineer new bone using a transient cartilage scaffold to induce endochondral ossification. Chondrocyte/chitosan scaffolds (both a transient cartilage scaffold-experimental-and a permanent cartilage scaffold-control) were prepared and implanted subcutaneously in nude mice. Bone formation was evaluated over a period of 5 months. Mineralization was assessed by Faxitron, micro computed tomography, backscatter electrons, and Fourier transform infrared spectroscopy analyses. Histological analysis provided further information on tissue changes in and around the implanted scaffolds. The deposition of ectopic bone was detected in the surface of the experimental implants as early as 1 month after implantation. After 3 months, bone trabeculae and bone marrow cavities were formed inside the scaffolds. The bone deposited was similar to the bone of the mice vertebra. Interestingly, no bone formation was observed in control implants. In conclusion, an engineered transient cartilage template carries all the signals necessary to induce endochondral bone formation in vivo. PMID:18759673

Oliveira, Serafim M; Mijares, Dindo Q; Turner, Gloria; Amaral, Isabel F; Barbosa, Mário A; Teixeira, Cristina C

2009-03-01

351

Tenofovir-associated bone density loss.  

PubMed

Clinical observations have revealed a strong correlation between loss of bone density in HIV-infected individuals, particularly in conjunction with the antiretroviral drug tenofovir, a nucleotide analog that inhibits HIV reverse transcriptase. The most compelling correlations have been observed in clinical studies involving young children and adolescents. These observations strongly suggest that bone density is being affected during active bone growth and development, implicating a role for tenofovir in bone loss. Here we discuss the literature and potential mechanisms for how tenofovir-associated bone loss may arise, which likely involves perturbation of cellular DNA synthesis and gene expression. Elucidation of the mechanism(s) involved in tenofovir-mediated bone loss will help in developing adjuvant therapies to reduce tenofovir-associated bone density loss. PMID:20169035

Grigsby, Iwen F; Pham, Lan; Mansky, Louis M; Gopalakrishnan, Raj; Mansky, Kim C

2010-01-01

352

Imagistic evaluation of matrix bone interface  

NASA Astrophysics Data System (ADS)

The problematic elements of bone regenerative materials are represented by their quality control methods. The defects repaired by bone grafting material were evaluated by en face optical coherence tomography and by synchrotron radiation micro-CT. The images obtained by efOCT show defects in some of the investigated samples, at the bone interface with different osteoconductive bone substitutes and we were able to detect gaps as small as 50 ?m. After the common synchrotron radiation micro-CT investigations, the slides were reconstructed and the 3D model was obtained. Along with the possibility of navigating inside the structure, one big advantage of this technique was pointed out: the remaining regenerative materials can be separated from the normal bone and the new bone can be visualized. Optical coherence tomography can be performed in vivo and can provide a qualitative and quantitative evaluation of the bone augmentation procedure.

Negruţiu, Meda L.; Sinescu, Cosmin; Manescu, Adrian; Topal?, Florin I.; Hoinoiu, Bogdan; M?rc?uţeanu, Corina; Duma, Virgil; Bradu, Adrian; Podoleanu, Adrian G.

2014-01-01

353

Effects of Cirrhosis on Bone Mineral Density and Bone Metabolism  

PubMed Central

Objective: The present study was undertaken to examine the correlation between the severity of liver disease and the presence and severity of bone disease in patients with hepatic cirrhosis. Materials and Methods: Between January 2005 and February 2006, 40 patients with cirrhosis and 22 healthy controls were enrolled in a cross-sectional study. All subjects underwent standard laboratory testing and bone densitometric studies of the lumbar spine and femoral neck using dual X-ray absorptiometry (DEXA). Results: Cirrhotic patients had lower serum follicle-stimulating hormone (FSH) levels than controls. Male patients had lower serum free testosterone (fT) levels than male controls. 25-hydroxyvitamin D (25-OHD3) levels were significantly higher in the controls as compared to patients with cirrhosis. In the cirrhotic group, 25-OHD3 concentrations did not differ significantly between patients with Child B and C class cirrhosis. As compared to the control group, cirrhotic patients had significantly elevated levels of urinary deoxypyridinoline (DPD). The cirrhotic patients also had a significantly lower mean spinal (SD) bone mineral density (BMD) than the control group. BMD of the lumbar spine (LS) was noted to be significantly lower in the Child C group than in the Child B group. In the cirrhotic patients, there was a positive correlation between the BMD T score of the femoral neck (FN) and albumin levels whereas there was a negative correlation between BMD T scores of the FN and age, bilirubin and prothrombin time (PT). Conclusion: Osteopenia and osteoporosis are highly prevalent in individuals with liver cirrhosis. Cirrhotic patients should undergo routine bone densitometric assessment and, if necessary, be treated for osteoporosis.

Turkeli, Mehmet; Dursun, Hakan; Albayrak, Fatih; Okçu, Nihat; Uyanik, M. Hamidullah; Uyanik, Abdullah; Y?ld?r?m, Rah?an; Kele?, Mustafa; Y?lmaz, Omer

2008-01-01

354

Dietary protein and bone health.  

PubMed

The effects of dietary protein on bone health are paradoxical and need to be considered in context of the age, health status and usual diet of the population. Over the last 80 years numerous studies have demonstrated that a high protein intake increases urinary Ca excretion and that on average 1 mg Ca is lost in urine for every 1 g rise in dietary protein. This relationship is primarily attributable to metabolism of S amino acids present in animal and some vegetable proteins, resulting in a greater acid load and buffering response by the skeleton. However, many of these early studies that demonstrated the calciuric effects of protein were limited by low subject numbers, methodological errors and the use of high doses of purified forms of protein. Furthermore, the cross-cultural and population studies that showed a positive association between animal-protein intake and hip fracture risk did not consider other lifestyle or dietary factors that may protect or increase the risk of fracture. The effects of protein on bone appear to be biphasic and may also depend on intake of Ca- and alkali-rich foods, such as fruit and vegetables. At low protein intakes insulin-like growth factor production is reduced, which in turn has a negative effect on Ca and phosphate metabolism, bone formation and muscle cell synthesis. Although growth and skeletal development is impaired at very low protein intakes, it is not known whether variations in protein quality affect the achievement of optimal peak bone mass in adolescents and young adults. Prospective studies in the elderly in the USA have shown that the greatest bone losses occur in elderly men and women with an average protein intake of 16-50 g/d. Although a low protein intake may be indicative of a generally poorer diet and state of health, there is a need to evaluate whether there is a lower threshold for protein intake in the elderly in Europe that may result in increased bone loss and risk of osteoporotic fracture. PMID:15018487

Ginty, Fiona

2003-11-01

355

Bone mass and bone metabolic indices in male master rowers.  

PubMed

The purpose of this study was to assess bone mass and bone metabolic indices in master athletes who regularly perform rowing exercises. The study was performed in 29 men: 14 master rowers and 15 non-athletic, body mass index-matched controls. Dual-energy X-ray absorptiometry measurements of the areal bone mineral density (aBMD) were performed for the total body, regional areas (arms, total forearms, trunk, thoracic spine, pelvis, and legs), lumbar spine (L1-L4), left hip (total hip and femoral neck), and forearm (33 % radius of the dominant and nondominant forearm). Serum concentrations of osteocalcin, collagen type I cross-linked C-telopeptide, visfatin, resistin, insulin, and glucose were determined. Comparative analyses showed significantly lower levels of body fat and higher lean body mass values in the rowers compared to the control group. The rowers also had significantly higher values of total and regional (left arm, trunk, thoracic spine, pelvis, and leg) BMD, as well as higher BMD values for the lumbar spine and the left hip. There were significant differences between the groups with respect to insulin, glucose, and the index of homeostasis model assessment insulin resistance. In conclusion, the systematic training of master rowers has beneficial effects on total and regional BMD and may be recommended for preventing osteoporosis. PMID:25224128

Sliwicka, Ewa; Nowak, Alicja; Zep, Wojciech; Leszczy?ski, Piotr; Pilaczy?ska-Szcze?niak, Lucja

2014-09-16

356

[The influence of mesenchymal stem cells on bone tissue regeneration upon implantation of demineralized bone matrix].  

PubMed

Mesenchymal stem cells (MSC) are resident pluripotent cells of bone marrow stroma. MSC are able to differentiate into chondroblasts, adipocytes, neurons, glia, cardiomyocytes, or osteoblasts. The problem of MSC usage in cell therapy of bone defects is widely discussed at present. The experiments were carried out using rats of inbred line Wistar-Kyoto. MSC were isolated from bone marrow and cultivated in vitro. Demineralized bone matrices (DBM) were obtained from parietal bones of rats and hens. Part of DBM was loaded with MSC. Bone defects were made in cranium parietal regions. DBM with or without MSC or metal plates were transplanted in these regions. It was shown that the application of MSC increased angiogenesis and osteogenesis in the damaged bone. The implantation of rat's DBM with MSC led to the formation of a full value bone. MSC suppressed inflammation, when transplantation of hen's DBM was carried out. The application of MSC always improved bone tissue regeneration. PMID:16708836

Krugliakov, P V; Sokolova, I B; Zin'kova, N N; Vi?de, S V; Cherednichenko, N N; Kisliakova, T V; Polyntsev, D G

2005-01-01

357

Interaction among Cells of Bone, Immune System, and Solid Tumors Leads to Bone Metastases  

PubMed Central

Bone metastases are a dismal consequence for different types of solid tumors, such as breast, prostate, lung, and kidney cancer. The mechanisms regulating the interactions among bone, immune system, and tumor cells have been deeply investigated, and many studies are ongoing to define the specific role of the different cells in the bone metastatic process. The affinity of some tumors to growth in bone results from the special microenvironment provided by bone. Moreover, immune system and bone have a bidirectional relationship: bone cells express surface molecules ruling the expansion of hemopoietic stem cells from which all cells of the mammalian immune system derive, and various immunoregulatory cytokines influence the fate of bone cells. The last findings allow to extend the concept of vicious cycle and add T cells as mediators of the tumor growth in bone. PMID:23710201

Roato, Ilaria

2013-01-01

358

Uranium inhibits bone formation in physiologic alveolar bone modeling and remodeling  

SciTech Connect

The toxic effect of uranium (U) on bone modeling and remodeling was studied by performing histomorphometric measurements in the periodontal cortical bone of rats. Two different single intraperitoneal doses of uranyl nitrate (238U) were administered to two sets of rats respectively (2 and 0.8 mg/kg body wt). Rats treated with the first dose were killed 14 days postinjection (PI) and those treated with the second were killed 14, 30, and 60 days PI. The results revealed a decrease in bone formation in rats treated with uranium. On the remodeling side the decrease in bone formation was coupled to an increase in bone resorption on the 14th day PI. On the modeling side no bone resorption was observed and the decrease in bone formation was linked to an increase in resting bone zones. Bone formation depression as a key event in U intoxication is stressed.

Ubios, A.M.; Guglielmotti, M.B.; Steimetz, T.; Cabrini, R.L. (Univ. of Buenos Aires (Argentina))

1991-02-01

359

Differences of osteoblastic bone metastases and osteolytic bone metastases in clinical features and molecular characteristics.  

PubMed

Several cancers tend to metastasize to bone, leading to osteolytic or osteoblastic bone lesions. The respective phenotypes of bone destruction and bone formation vary in clinical features, including incidence, prognosis, skeletal-related events and bone biomarkers. In addition, different molecular mechanisms explain the difference in phenotype. For example, molecules involved in osteolytic bone metastases (represented with breast cancer) include parathyroid hormone-related protein, transforming growth factor-?, while in osteoblastic lesions (represented with prostate cancer), endothelin-1 and morphogenetic proteins, etc. play a more important role in bone formation. It is important for us to understand the differences of bone metastases between two phenotypes to help clinicians to understand the underlying mechanisms, behaviors and therapies in development and currently available for bone metastases. PMID:25351174

Fang, J; Xu, Q

2015-03-01

360

Anterior lumbar intervertebral fusion with artificial bone in place of autologous bone.  

PubMed

The feasibility of anterior lumbar intervertebral fusion with artificial bone in place of autogenous bone was investigated. Porous hydroxyapatite (HA)/ZrO2 ceramics loading bone morphogenetic protein (BMP) were implanted after removal of lumbar vertebral disc in rabbits. The adjacent intervertebral discs were also removed by the same way and autogenous illic bone was implanted. SEM observation and biomechanical test were carried out. Compound bone had a bit lower osteoinductive activity than autogenous bone by SEM (Osteoinductive activity of artificial bone in 12 weeks was the same as that of autogenous bone in 9 weeks). Biomechanical test revealed that compound bone had lower anti-pull strength than autogenous bone (P < 0.001), but there was no significant difference in anti-pull strength between compound bone at 12th week and autogenous bone at 9th week (P > 0.05). It was concluded that compound bone could be applied for anterior spinal fusion, especially for those patients who can't use autogenous bone. PMID:14526441

Xu, Weiguo; Chen, Anmin; Feng, Xu; Yin, Weifeng

2003-01-01

361

Lesions of bone and bone marrow in myeloid leukosis occurring naturally in adult broiler breeders.  

PubMed

Lesions of bone and bone marrow in myeloid leukosis (ML) occurring naturally in adult broiler breeders were investigated pathologically. During gross examination, nodules and protrusions were commonly observed on the surface of the sternum, ribs, vertebrae, and synsacrum. The bone marrow of all the bones of the body was pale in color. Histologically, granulated myelocytes proliferated in the bone marrow of various bones and in the periosteum of the sternum, ribs, vertebrae, and synsacrum. The first proliferation of tumor cells occurred in the bone marrow of epiphysis. The myelocytes invaded through haversian and Volkmann's canals from the bone marrow to periosteal areas. Hematopoiesis was suppressed by marked proliferation of tumor cells in the bone marrow of the whole bone. Atrophy was also seen in the bones, including medullary bones of the chickens suffering from ML. Proliferation of myelocytes was seen in the bone marrow and periosteum of ossified cartilaginous rings of the trachea and larynx. Marked proliferation of myelocytes was seen in the dura mater of spinal cords, and it subsequently depressed the spinal cords. Bone formation with cartilage was seen in the periosteum of the sternum having marked proliferation of myelocytes in the bone marrow and periosteum. Ultrastructurally, tumor cells showed large nuclei and cytoplasm with large round electron-dense lysosomes. The virus particles were rarely detected in the cytoplasm of tumor cells. The polymerase chain reaction test of tumor samples showed positive for subgroup J avian leukosis virus. This study indicates that the myelocytes can invade through the compact bones to the periosteum in the sternum, ribs, vertebrae, synsarcum, and ossified cartilage of trachea and larynx having thinner compact bones. In addition, the periosteal osteogenesis with cartilage in the sternum may be reactive change against the bone atrophy because of the marked proliferation of myelocytes. PMID:10737666

Nakamura, K; Ogiso, M; Tsukamoto, K; Hamazaki, N; Hihara, H; Yuasa, N

2000-01-01

362

In vitro simulation of pathological bone conditions to predict clinical outcome of bone tissue engineered materials  

NASA Astrophysics Data System (ADS)

According to the Centers for Disease Control, the geriatric population of ?65 years of age will increase to 51.5 million in 2020; 40% of white women and 13% of white men will be at risk for fragility fractures or fractures sustained under normal stress and loading conditions due to bone disease, leading to hospitalization and surgical treatment. Fracture management strategies can be divided into pharmaceutical therapy, surgical intervention, and tissue regeneration for fracture prevention, fracture stabilization, and fracture site regeneration, respectively. However, these strategies fail to accommodate the pathological nature of fragility fractures, leading to unwanted side effects, implant failures, and non-unions. Compromised innate bone healing reactions of patients with bone diseases are exacerbated with protective bone therapy. Once these patients sustain a fracture, bone healing is a challenge, especially when fracture stabilization is unsuccessful. Traditional stabilizing screw and plate systems were designed with emphasis on bone mechanics rather than biology. Bone grafts are often used with fixation devices to provide skeletal continuity at the fracture gap. Current bone grafts include autologous bone tissue and donor bone tissue; however, the quality and quantity demanded by fragility fractures sustained by high-risk geriatric patients and patients with bone diseases are not met. Consequently, bone tissue engineering strategies are advancing towards functionalized bone substitutes to provide fracture reconstruction while effectively mediating bone healing in normal and diseased fracture environments. In order to target fragility fractures, fracture management strategies should be tailored to allow bone regeneration and fracture stabilization with bioactive bone substitutes designed for the pathological environment. The clinical outcome of these materials must be predictable within various disease environments. Initial development of a targeted treatment strategy should focus on simulating, in vitro, a physiological bone environment to predict clinical effectiveness of engineered bone and understand cellular responses due to the proposed agents and bioactive scaffolds. An in vitro test system can be the necessary catalyst to reduce implant failures and non-unions in fragility fractures.

Nguyen, Duong Thuy Thi

363

Adaptation Models of Anisotropic Bone.  

PubMed

A theoretical model and numerical methods were developed for testing different bone internal remodelling stimuli. The keystone of the study was the formulation of a stimulus based on the mechanical invariants of the stress tensor, which took into account bone non-homogeneity and anisotropy. A non-site specific remodelling rate equation was then used for the apparent density whereas anisotropy was fixed and evaluated from anatomic observations. An node-based semi-implicit algorithm with adaptive stepsize was implemented for solving the evolution equation. To preclude numerical artifacts (non-convergence, instability), a phase space description was proposed. As an illustration, the evolution of apparent density distribution surrounding the femoral stem after a Total Hip Replacement was simulated. Three stimuli were tested: the strain energy density stimulus, the octahedral shear stress stimulus, and an anisotropic plastic yield stress stimulus. PMID:11264796

Terrier, A.; Rakotomanana, R. L.; Ramaniraka, A. N.; Leyvraz, P. F.

1997-01-01

364

Gene Therapy for Bone Engineering  

PubMed Central

Bone has an intrinsic healing capacity that may be exceeded when the fracture gap is too big or unstable. In that moment, osteogenic measures need to be taken by physicians. It is important to combine cells, scaffolds and growth factors, and the correct mechanical conditions. Growth factors are clinically administered as recombinant proteins. They are, however, expensive and needed in high supraphysiological doses. Moreover, their half-life is short when administered to the fracture. Therefore, gene therapy may be an alternative. Cells can constantly produce the protein of interest in the correct folding, with the physiological glycosylation and in the needed amounts. Genes can be delivered in vivo or ex vivo by viral or non-viral methods. Adenovirus is mostly used. For the non-viral methods, hydrogels and recently sonoporation seem to be promising means. This review will give an overview of recent advancements in gene therapy approaches for bone regeneration strategies.

Balmayor, Elizabeth Rosado; van Griensven, Martijn

2015-01-01

365

[Advances in bone densitometry equipment].  

PubMed

Techniques in bone densitometry have made remarkable progress in the past quarter-century and are now widely used in the daily practice of osteoporosis. Since the skeletal site and the method of measurement differ among the type of equipments, several types are adopted to suit the situation of each medical institute. Central DXA is used to provide a thorough examination of osteoporosis in large hospitals, whereas in general clinics the radial DXA or radiographic photodensitometry of metacarpus is mainly used. Quantitative ultrasound of calcaneus is mostly used for screening osteoporosis. DXA is also going to be applied to vertebral fracture assessment, hip structural analysis and micro-architectural analysis of vertebral trabecular bone. PMID:23445883

Sone, Teruki; Ohnaru, Kazuhiro; Tanaka, Kensuke

2013-03-01

366

Predicting Bone Mechanical Properties of Cancellous Bone from DXA, MRI, and Fractal Dimensional Measurements  

NASA Technical Reports Server (NTRS)

This project was aimed at making predictions of bone mechanical properties from non-invasive DXA and MRI measurements. Given the bone mechanical properties, stress calculations can be made to compare normal bone stresses to the stresses developed in exercise countermeasures against bone loss during space flight. These calculations in turn will be used to assess whether mechanical factors can explain bone loss in space. In this study we assessed the use of T2(sup *) MRI imaging, DXA, and fractal dimensional analysis to predict strength and stiffness in cancellous bone.

Harrigan, Timothy P.; Ambrose, Catherine G.; Hogan, Harry A.; Shackleford, Linda; Webster, Laurie; LeBlanc, Adrian; Lin, Chen; Evans, Harlan

1997-01-01

367

Pathologic bone tissues in a Turkey vulture and a nonavian dinosaur: implications for interpreting endosteal bone and radial fibrolamellar bone in fossil dinosaurs.  

PubMed

We report on similar pathological bone microstructure in an extant turkey vulture (Cathartes aura) and a nonavian dinosaur from Transylvania. Both these individuals exhibit distinctive periosteal reactive bone deposition accompanied by endosteal bone deposits in the medullary cavity. Our findings have direct implications on the two novel bone tissues recently described among nonavian dinosaurs, radial fibrolamellar bone tissue and medullary bone tissue. On the basis of the observed morphology of the periosteal reactive bone in the turkey vulture and the Transylvanian dinosaur, we propose that the radial fibrolamellar bone tissues observed in mature dinosaurs may have had a pathological origin. Our analysis also shows that on the basis of origin, location, and morphology, pathologically derived endosteal bone tissue can be similar to medullary bone tissues described in nonavian dinosaurs. As such, we caution the interpretation of all endosteally derived bone tissue as homologous to avian medullary bone. PMID:19711479

Chinsamy, Anusuya; Tumarkin-Deratzian, Allison

2009-09-01

368

Bacterially induced bone destruction: mechanisms and misconceptions.  

PubMed Central

Normal bone remodelling requires the coordinated regulation of the genesis and activity of osteoblast and osteoclast lineages. Any interference with these integrated cellular systems can result in dysregulation of remodelling with the consequent loss of bone matrix. Bacteria are important causes of bone pathology in common conditions such as periodontitis, dental cysts, bacterial arthritis, and osteomyelitis. It is now established that many of the bacteria implicated in bone diseases contain or produce molecules with potent effects on bone cells. Some of these molecules, such as components of the gram-positive cell walls (lipoteichoic acids), are weak stimulators of bone resorption in vitro, while others (PMT, cpn60) are as active as the most active mammalian osteolytic factors such as cytokines like IL-1 and TNF. The complexity of the integration of bone cell lineage development means that there are still question marks over the mechanism of action of many well-known bone-modulatory molecules such as parathyroid hormone. The key questions which must be asked of the now-recognized bacterial bone-modulatory molecules are as follows: (i) what cell population do they bind to, (ii) what is the nature of the receptor and postreceptor events, and (iii) is their action direct or dependent on the induction of secondary extracellular bone-modulating factors such as cytokines, eicosanoids, etc. In the case of LPS, this ubiquitous gram-negative polymer probably binds to osteoblasts or other cells in bone through the CD14 receptor and stimulates them to release cytokines and eicosanoids which then induce the recruitment and activation of osteoclasts. This explains the inhibitor effects of nonsteroidal and anticytokine agents on LPS-induced bone resorption. However, other bacterial factors such as the potent toxin PMT may act by blocking the normal maturation pathway of the osteoblast lineage, thus inducing dysregulation in the tightly regulated process of resorption and replacement of bone matrix. At the present time, it is not possible to define a general mechanism by which bacteria promote loss of bone matrix. Many bacteria are capable of stimulating bone matrix loss, and the information available would suggest that each organism possesses different factors which interact with bone in different ways. With the rapid increase in antibiotic resistance, particularly with Staphylococcus aureus and M. tuberculosis, organisms responsible for much bone pathology in developed countries only two generations ago, we would urge that much greater attention should be focused on the problem of bacterially induced bone remodelling in order to define pathogenetic mechanisms which could be therapeutic targets for the development of new treatment modalities. PMID:8698454

Nair, S P; Meghji, S; Wilson, M; Reddi, K; White, P; Henderson, B

1996-01-01

369

Bone health in multiple sclerosis  

Microsoft Academic Search

People who are disabled with multiple sclerosis (MS) may be at increased risk of osteoporosis. This review discusses issues\\u000a relevant to bone health in MS and makes practical recommendations regarding prevention and screening for osteoporosis and\\u000a fracture risk in MS. A search of the literature up until 5 April 2011 was performed using key search terms, and articles pertinent\\u000a to

J. C. Gibson; G. D. Summers

370

Bone Woman: poetry and fictions  

E-print Network

: English BONK WOMAN: POETRY AND FICTIONS A Thesis by TRIA ELLEN AIRHEART-MARTIN Submitted to Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF ARTS Approved as to style and content by: Paul Christensen.... , Texas ARM University Chair of Advisory Committee: Dr. Paul Christensen This creative thesis is a collection of poetry and short fiction. The Native American legend of Bone Woman is explored as an analogy for the creative process; the author's works...

Airheart-Martin, Tria Ellen

1997-01-01

371

The temporal response of bone to unloading  

NASA Technical Reports Server (NTRS)

Rats were suspended by their tails with the forelimbs bearing the weight load to simulate the weightlessness of space flight. Growth in bone mass ceased by 1 week in the hindlimbs and lumbar vertebrae in growing rats, while growth in the forelimbs and cervical vertebrae remained unaffected. The effects of selective skeletal unloading on bone formation during 2 weeks of suspension was investigated using radio iostope incorporation (with Ca-45 and H-3 proline) and histomorphometry (with tetracycline labeling). The results of these studies were confirmed by histomorphometric measurements of bone formation using triple tetracycline labeling. This model of simulated weightlessness results in an initial inhibition of bone formation in the unloaded bones. This temporary cessation of bone formation is followed in the accretion of bone mass, which then resumes at a normal rate by 14 days, despite continued skeletal unloading. This cycle of inhibition and resumption of bone formation has profound implication for understanding bone dynamics durng space flight, immobilization, or bed rest and offers an opportunity to study the hormonal and mechanical factors that regulate bone formation.

Globus, R. K.; Bikle, D. D.; Morey-Holton, E.

1984-01-01

372

Osedax borings in fossil marine bird bones  

PubMed Central

The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth’s history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene. PMID:21103978

Kahl, Wolf-Achim; Goedert, James L.

2010-01-01

373

Mechanisms of osteoclast-dependent bone formation  

PubMed Central

Should we believe that osteoclasts are only involved in bone resorption? What about their contribution to bone formation? In this article I will review evidence that bone formation can be regulated by osteoclasts. Why is this? Likely because in the physiologic condition of bone remodeling, bone resorption and formation are balanced, and there is no better way to control this equilibrium than through a concerted action between the two cell types. Although the influence of osteoblasts on osteoclastic bone resorption is well documented and consolidated over time, what osteoclasts do to regulate osteoblast activity is still matter of intense investigation. The original hypothesis that all is in the osteoblast-seeking factors stored in the bone matrix, released and activated during bone resorption, is now being challenged by several studies, suggesting that osteoclasts are also capable of producing ‘clastokines' that regulate osteoblast performance. Indeed, several of them have been demonstrated to orchestrate osteoclast–osteoblast activities. However, we are probably still at the dawn of a new era, and future work will tell us whether any of these clastokines can be exploited to stimulate bone formation and rebalance bone remodeling in skeletal diseases. PMID:24422142

Teti, Anna

2013-01-01

374

Effortless Effort in Bone Regeneration: A Review  

PubMed Central

Since the beginning of the 20th century, the concept of osteoconduction in bony changes in the oral cavity showed a wide range of biomaterials and their osteoinductive potential that emerged gradually and has to a large extent improved the quality of the bone prior to the placement of an implant. Alveolar bone loss is a major concern after tooth extraction in patients and therefore atraumatic extraction procedures should be followed to avoid further bone loss. To overcome the alveolar bone loss and to augment support for placing dental implants, many bone regenerative substitutes are available such as allografts, autografts, xenografts, synthetic biomaterials and osteoactive agents. In light of the steady progress in bone grafting techniques and graft materials, it has become possible to improve the volume, width, and height of bone in deficient areas of the oral cavity. These advances in regenerative dentistry thus facilitate an easy and convenient placement of an implant in an ideal position and angulations resulting in superior esthetics and function. Bone grafting materials and their substitutes are the alternative filler materials, which facilitate to reduce additional surgical procedures, risks, chances of cross infection involved in placing autografts and allografts into the bony structures. This review literature highlights various biomaterials that are helpful in bone healing and thus create an anatomically favorable base for ideal implant placement. How to cite the article: Nazirkar G, Singh S, Dole V, Nikam A. Effortless effort in bone regeneration: A review. J Int Oral Health 2014;6(3):120-4. PMID:25083047

Nazirkar, Girish; Singh, Shailendra; Dole, Vinaykumar; Nikam, Akhilesh

2014-01-01

375

Hypergravity suppresses bone resorption in ovariectomized rats  

NASA Astrophysics Data System (ADS)

The effects of gravity on bone metabolism are unclear, and little has been reported about the effects of hypergravity on the mature skeleton. Since low gravity has been shown to decrease bone volume, we hypothesized that hypergravity increases bone volume. To clarify this hypothesis, adult female rats were ovariectomized and exposed to hypergravity (2.9G) using a centrifugation system. The rats were killed 28 days after the start of loading, and the distal femoral metaphysis of the rats was studied. Bone architecture was assessed by micro-computed tomography (micro-CT) and bone mineral density was measured using peripheral quantitative CT (pQCT). Hypergravity increased the trabecular bone volume of ovariectomized rats. Histomorphometric analyses revealed that hypergravity suppressed both bone formation and resorption and increased bone volume in ovariectomized rats. Further, the cell morphology, activity, proliferation, and differentiation of osteoclasts and osteoblasts exposed to hypergravity were evaluated in vitro. Hypergravity inhibited actin ring formation in mature osteoclasts, which suggested that the osteoclast activity was suppressed. However, hypergravity had no effect on osteoblasts. These results suggest that hypergravity can stimulate an increase in bone volume by suppressing bone resorption in ovariectomized rats.

Ikawa, Tesshu; Kawaguchi, Amu; Okabe, Takahiro; Ninomiya, Tadashi; Nakamichi, Yuko; Nakamura, Midori; Uehara, Shunsuke; Nakamura, Hiroaki; Udagawa, Nobuyuki; Takahashi, Naoyuki; Nakamura, Hiroaki; Wakitani, Shigeyuki

2011-04-01

376

Bone Tissue Engineering: Recent Advances and Challenges  

PubMed Central

The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

2013-01-01

377

Physiological effects of microgravity on bone cells.  

PubMed

Life on Earth developed under the influence of normal gravity (1g). With evidence from previous studies, scientists have suggested that normal physiological processes, such as the functional integrity of muscles and bone mass, can be affected by microgravity during spaceflight. During the life span, bone not only develops as a structure designed specifically for mechanical tasks but also adapts for efficiency. The lack of weight-bearing forces makes microgravity an ideal physical stimulus to evaluate bone cell responses. One of the most serious problems induced by long-term weightlessness is bone mineral loss. Results from in vitro studies that entailed the use of bone cells in spaceflights showed modification in cell attachment structures and cytoskeletal reorganization, which may be involved in bone loss. Humans exposed to microgravity conditions experience various physiological changes, including loss of bone mass, muscle deterioration, and immunodeficiency. In vitro models can be used to extract valuable information about changes in mechanical stress to ultimately identify the different pathways of mechanotransduction in bone cells. Despite many in vivo and in vitro studies under both real microgravity and simulated conditions, the mechanism of bone loss is still not well defined. The objective of this review is to summarize the recent research on bone cells under microgravity conditions based on advances in the field. PMID:24687524

Arfat, Yasir; Xiao, Wei-Zhong; Iftikhar, Salman; Zhao, Fan; Li, Di-Jie; Sun, Yu-Long; Zhang, Ge; Shang, Peng; Qian, Ai-Rong

2014-06-01

378

Vancomycin iontophoresis of allograft bone  

PubMed Central

Objectives The most concerning infection of allografts and operative procedures is methicillin resistant Staphylococcus aureus (MRSA) and no current iontophoresed antibiotics effectively combat this microbe. It was initially hypothesised that iontophoresis of vancomycin through bone would not be effective due to its large molecular size and lack of charge. The aim of this study was to determine whether this was a viable procedure and to find the optimum conditions for its use. Methods An iontophoresis cell was set up with varying concentrations of Vancomycin within the medulla of a section of sheep tibia, sealed from an external saline solution. The cell was run for varying times, Vancomycin concentrations and voltages, to gain information on optimisation of conditions for impregnating the graft. Each graft was then sectioned and dust ground from the exposed surface. The dust was serially washed to extract the Vancomycin and concentrations measured and plotted for all variables tested. Results Vancomycin was successfully delivered and impregnated to the graft using the iontophoresis technique. The first order fit to the whole data set gave a significant result (p = 0.0233), with a significant concentration (p = 0.02774) component. The time component was the next most significant (p = 0.0597), but did not exceed the 95% confidence level. Conclusions Iontophoresis is an effective method for delivering Vancomycin to allograft bone. The concentrations of the vancomycin solution affected the bone concentration, but results were highly variable. Further study should be done on the effectiveness of delivering different antibiotics using this method. PMID:24729101

Edmondson, M. C.; Day, R.; Wood, D.

2014-01-01

379

[Morphological analysis of bone dynamics and metabolic bone disease. Does bisphosphonate treatment cause severely suppressed bone turnover (SSBT) ?].  

PubMed

Bisphosphonates are anti-resorptive drug and increase both bone strength and toughness. However, their long term treatment oversuppresses bone turnover and promotes advanced glycation end-products in bone tissue, resulting in low bone quality. These conditions are called "severely suppressed bone turnover (SSBT) " , and can cause "atypical" , low-impact fractures of the femoral subtrochanteric or shaft. It is evident that bisphosphonates prevent fracture risk in vertebral body or femoral neck and improve quality of life in patients with osteoporosis, but clinicians, especially bone specialists, have to keep the associations between bisphosphonate use and SSBT in mind. Rational approach to atypical femoral subtrochanteric÷shaft fractures should be determined in near future. PMID:21447926

Kondo, Naoki; Yoda, Takuya

2011-04-01

380

Do porous calcium hydroxyapatite ceramics cause porosis in bone? A bone densitometry and biomechanical study on cortical bones of rabbits.  

PubMed

Porous calcium hydroxyapatite (CHA) ceramics are biocompatible and present osteoconductive properties. These ceramics are widely used in orthopaedic surgery; however, it is not yet known whether they have some adverse effects on bone and bone marrow healing. Our previous radiological study revealed possible local porosis at the adjacent sites of the CHA ceramic. Histological findings of the same study revealed bone marrow swelling and depletion at the implantation site. Osteoclasts removed particles of the implant that may be the cause of local porosis. In the present study, possible local osteoporosis was evaluated by bone densitometry analyses, and compression and three-point bending tests. CHA particles were implanted into the left limbs and a sham operation was utilized on the right limbs of 75 white rabbits. The animals were followed up for 23 weeks for bone mineral density and for 6 months for biomechanical analyses. The CHA implanted area and its distal or proximal adjacent areas were evaluated with a Hologic QDR-2000 bone densitometer. Three-point bending and compression tests were performed with an M-30 K material testing device. The results revealed a time-dependent bone density increase at the CHA implantation site and no significant porosis at adjacent areas of the implant. The stiffness of CHA-implanted bones in three-point bending is larger than that of the control group. CHA-implanted rabbit bones presented a different fracture pattern from the control group. The stiffness of the control and CHA-implanted bones generally increased with time indicating no adverse effects of porous CHA ceramics in bone and bone marrow healing. The clinical relevance of this work is that porous CHA ceramics do not cause local porosis at adjacent areas when implanted into osseous sites.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7492718

Korkusuz, F; Karamete, K; Irfano?lu, B; Yetkin, H; Hastings, G W; Akkas, N

1995-05-01

381

Magnesium-based bone cement and bone void filler: preliminary experimental studies.  

PubMed

Bone cement has great potential in craniofacial surgery in the repair of osseous defects secondary to surgery or trauma. This includes the use of bone cement as a bone void filler for full-thickness cranial defects and as augmentation of deficient bones. Ideally, this material should be easily available, biocompatible, resorbable, bone inductive, and have adhesive qualities to bone. Calcium-based bone cements have some of these qualities but have a higher than desirable failure rate. OsteoCrete, a new magnesium-based bone cement and bone void filler, was compared to Norian in critical-sized skull defects and cementing bone flaps in rabbits. Both materials were successful; however, OsteoCrete had a faster resorption and replacement by bone rate than Norian. Bone flap position and apparent stability were also superior with OsteoCrete. There were no adverse reactions to either cement. A magnesium-based bone cement presents with advantages when compared with a comparator calcium-based cement in craniofacial surgery. PMID:19305245

Schendel, Stephen A; Peauroi, John

2009-03-01

382

Influence of Ovariectomy on Bone Turnover and Trabecular Bone Mass in Mature Cynomolgus Monkeys  

PubMed Central

Purpose To examine the influence of ovariectomy (OVX) on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites in mature cynomolgus monkeys. Materials and Methods Six female cynomolgus monkeys, aged 17-21 years, were randomized into 2 groups by the stratified weight: the OVX and sham-operation groups (n = 3 in each group). The experimental period was 16 months. Lumbar bone mineral density (BMD) in vivo and serum and urinary bone turnover markers were longitudinally measured, and peripheral quantitative computed tomographic and bone histomorphometric analyses were performed on trabecular bone of the lumbar vertebra, femoral neck, and distal radius at the end of the experiment. Results OVX induced in a reduction in lumbar BMD compared with the sham controls and the baseline, as a result of increased serum levels of bone-specific alkaline phosphatase and urinary levels of cross-lined N- and C-terminal telopeptides of type I collagen. Furthermore, OVX induced reductions in trabecular volumetric BMD and trabecular bone mass compared with the sham controls, with increased bone formation rate at the lumbar vertebra, femoral neck, and distal radius. Conclusion The results indicated that OVX in mature cynomolgus monkeys (17-21 years of age) increased bone turnover and induced trabecular bone loss at the three skeletal sites compared with the sham controls. Thus, mature cynomolgus monkeys could be utilized for preclinical studies to examine the effects of interventions on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites. PMID:19568597

Seki, Azusa; Matsuura, Masao; Sato, Yoshihiro; Takeda, Tsuyoshi; Matsumoto, Hideo; Yeh, James K.

2009-01-01

383

Bone and Calcium Metabolism During Space Flight  

NASA Technical Reports Server (NTRS)

Understanding bone loss during space flight is one of the most critical challenges for maintaining astronaut health on space exploration missions. Flight and ground-based studies have been conducted to better understand the nature and mechanisms of weightlessness-induced bone loss, and to identify a means to counteract the loss. Maintenance of bone health requires a balance between bone formation and bone resorption. Early space research identified bone loss as a critical health issue, but could not provide a distinction between the bone formation and breakdown processes. The recent identification of collagen crosslinks as markers of bone resorption has made possible a clear understanding that a decrease in bone resorption is an important effect of space flight, with bone formation being unchanged or only slightly decreased. Calcium regulatory factors have also been studied, in an attempt to understand their role in bone loss. The lack of ultraviolet light exposure and insufficient dietary sources of vitamin D often lead to reduced vitamin D stores on long-duration flights. Serum parathyroid hormone (PTH) concentrations are decreased during flight compared to before flight, although small subject numbers often make this hard to document statistically. As expected, reduced PTH concentrations are accompanied by reduced 1,25-dihydroxyvitamin D concentrations. Calcium kinetic studies during space flight confirm and extend the information gained from biochemical markers of bone metabolism. Calcium kinetic studies demonstrate that bone resorption is increased, bone formation is unchanged or decreased, and dietary calcium absorption is reduced during space flight. Evaluations have also been conducted of countermeasures, including dietary, exercise, and pharmacological treatments. In recent studies, many potential countermeasures show promise at mitigating bone loss in ground-based analogs of weightlessness (e.g., bed rest), but require further ground and flight testing to ensure that the beneficial effects are seen in space flight. As we begin to plan for missions to go back to the Moon, and even off to Mars, many questions are yet to be answered. Maintaining bone is one of the greatest challenges, but with a better understanding of the mechanical processes of bone loss, countermeasures can be designed more efficiently, and the solution (or solutions) may be just over the horizon.

Smith, Scott M.

2004-01-01

384

Bone banking in a community hospital.  

PubMed

Major orthopaedic operations are now also performed in community hospitals. Because allografts are sometimes used during these procedures, local bone banking could become an essential tool. We evaluated the indications and results of the allografts from the local bone bank used in our institution. The financial aspect was also examined. Of the 131 allografts stored in our bone bank, only 20 were discarded. Postoperative follow-up showed good ingrowth of the grafts except for one graft failure. There were no superficial or deep postoperative infections. All cultures taken during implantation remained negative. These data suggest that bone banking in a community hospital is a safe and practical alternative to address the ongoing demand of bone grafts in a small orthopaedic practice. Financial costs are reasonable. In our experience, bone banking also broadens the spectrum of orthopaedic operations that can be performed in an orthopaedic unit. PMID:18260489

Meermans, Geert; Roos, Jaak; Hofkens, Lieven; Cheyns, Paul

2007-12-01

385

Regulation of bone mineral loss during lactation  

NASA Technical Reports Server (NTRS)

The effects of varyng dietary calcium and phosphorous levels, vitamin D deficiency, oophorectomy, adrenalectomy, and simultaneous pregnancy on bone mineral loss during lactation in rats are studied. The experimental procedures and evaluations are described. The femur ash weight of lactating and nonlactating rats are calculated. The data reveals that a decrease in dietary calcium of 0.02 percent results in an increased loss of bone mineral, an increase in calcium to 1.4 percent does not lessen bone mineral loss, and bone mineral loss in vitamin D deficient rats is independent of calcium levels. It is observed that changes in dietary phosphorous level, oophorectomy, adrenalectomy, and simultaneous pragnancy do not reduce bone mineral loss during lactation. The analysis of various hormones to determine the mechanism that triggers bone mineral loss during lactation is presented.

Brommage, R.; Deluca, H. F.

1985-01-01

386

Bone Vascularization in Normal and Disease Conditions  

PubMed Central

Bone vasculature is essential for many processes, such as skeletal development and growth, bone modeling and remodeling, and healing processes. Endothelium is an integral part of bone tissue, expressing a physiological paracrine function via growth factors and chemokines release, and interacting with several cellular lines. Alterations of the complex biochemical interactions between vasculature and bone cells may lead to various clinical manifestations. Two different types of pathologies result: a defect or an excess of bone vasculature or endothelium metabolism. Starting from the molecular basis of the interactions between endothelial and bone cells, the Authors present an overview of the recent acquisitions in the physiopathology of the most important clinical patterns, and the modern therapeutic strategies for their treatments. PMID:23986744

Carulli, Christian; Innocenti, Massimo; Brandi, Maria Luisa

2013-01-01

387

Marrow Fat and Bone—New Perspectives  

PubMed Central

Context: There is growing interest in the relationship between bone mineral density, bone strength, and fat depots. Marrow adipose tissue, a well-established component of the marrow environment, is metabolically distinct from peripheral fat depots, but its functional significance is unknown. Objective: In this review, we discuss animal and human data linking the marrow adipose tissue depot to parameters of bone density and integrity as well as the potential significance of marrow adipose tissue in metabolic diseases associated with bone loss, including type 1 diabetes mellitus and anorexia nervosa. Potential hormonal determinants of marrow adipose tissue are also discussed. Conclusions: We conclude that whereas most animal and human data demonstrate an inverse association between marrow adipose tissue and measures of bone density and strength, understanding the functional significance of marrow adipose tissue and its hormonal determinants will be critical to better understanding its role in skeletal integrity and the role of marrow adipose tissue in the pathophysiology of bone loss. PMID:23393168

Fazeli, Pouneh K.; Horowitz, Mark C.; MacDougald, Ormond A.; Scheller, Erica L.; Rodeheffer, Matthew S.; Rosen, Clifford J.

2013-01-01

388

Bone Metabolism in Obesity and Weight Loss  

PubMed Central

Excess body weight due to obesity has traditionally been considered to have a positive effect on bone; however, more recent findings suggest that bone quality is compromised. Both obesity and caloric restriction increase fracture risk and are regulated by endocrine factors and cytokines that have direct and indirect effects on bone and calcium absorption. Weight reduction will decrease bone mass and mineral density, but this varies by the individual’s age, gender, and adiposity. Dietary modifications, exercise, and medications have been shown to attenuate the bone loss associated with weight reduction. Future obesity and weight loss trials would benefit from assessment of key hormones, adipokine and gut peptides that regulate calcium absorption, and bone mineral density and quality by using sensitive techniques in high-risk populations. PMID:22809104

Shapses, Sue A.; Sukumar, Deeptha

2014-01-01

389

Vitamin C Prevents Hypogonadal Bone Loss  

PubMed Central

Epidemiologic studies correlate low vitamin C intake with bone loss. The genetic deletion of enzymes involved in de novo vitamin C synthesis in mice, likewise, causes severe osteoporosis. However, very few studies have evaluated a protective role of this dietary supplement on the skeleton. Here, we show that the ingestion of vitamin C prevents the low-turnover bone loss following ovariectomy in mice. We show that this prevention in areal bone mineral density and micro-CT parameters results from the stimulation of bone formation, demonstrable in vivo by histomorphometry, bone marker measurements, and quantitative PCR. Notably, the reductions in the bone formation rate, plasma osteocalcin levels, and ex vivo osteoblast gene expression 8 weeks post-ovariectomy are all returned to levels of sham-operated controls. The study establishes vitamin C as a skeletal anabolic agent. PMID:23056580

Zhu, Ling-Ling; Cao, Jay; Sun, Merry; Yuen, Tony; Zhou, Raymond; Li, Jianhua; Peng, Yuanzhen; Moonga, Surinder S.; Guo, Lida; Mechanick, Jeffrey I.; Iqbal, Jameel; Peng, Liu; Blair, Harry C.; Bian, Zhuan; Zaidi, Mone

2012-01-01

390

Trabecular bone failure at the microstructural level.  

PubMed

Although biomedical imaging technology is now readily available, few attempts have been made to expand the capabilities of these systems by adding not only quantitative but also functional analysis tools combining microimaging with time-lapsed mechanical testing. An area of special interest is multiscale functional imaging of trabecular bone to assess the relative importance of bone "quality" in the assessment of the mechanical competence of bone. First, relevant studies dealing with hierarchical imaging of trabecular bone and classic analyses such as quantitative morphometry and finite-element analysis to predict bone strength are reviewed. Second, studies are presented investigating failure mechanisms of three-dimensional trabecular bone through dynamic, time-lapsed microimaging, including image-guided techniques developed for this purpose and utilizing microcompression. For the first time, these allow the direct three-dimensional visualization and quantification of failure initiation and progression at the microstructural level. PMID:16822408

Müller, Ralph; van Lenthe, G Harry

2006-06-01

391

Bone biopsy as a screening technique for bone bank allograft donation.  

PubMed

The objective of the study was to investigate occult abnormalities in bone bank allograft with the use of histomorphometry that may otherwise go unidentified with current screening techniques. This was a prospective pathology review in which 40 transcortical trephine bone biopsies were taken from the iliac crest of bone donors and examined by light microscopy and semiautomated histomorphometry. Current routine screening techniques for allograft bone donors include history, serology, and culture. Additional screening for unsuspected pathology and for parameters related to metabolic bone disease may predict the effectiveness of the donor bone. Light-microscopic findings showed 1 case suspicious for chronic myeloproliferative disorder, which had otherwise not been detected by standard screening techniques. On histomorphometric analysis, 3 specimens showed severe osteoporosis. In conclusion, iliac crest bone biopsy may need to be considered as an adjunct in screening for both unsuspected hematological disease and metabolic bone disease. PMID:15074459

Siddiqui, Saqib A; Lipton, Jeffrey F; Vigorita, Vincent J; Evangelista, John; Bryk, Eli

2004-03-01

392

[Encounter of cancer cells with bone. Treatment of bone metastases from breast cancer].  

PubMed

In metastatic breast cancer the most common metastatic site is bone. Skeletal-related events (SREs) as well as bone pain are well-known characteristics of bone metastasis. Activation of osteoclast is the most important mechanism for the progression of bone metastasis. To treat bone metastasis, not only administration of antitumor drug but also inhibition of osteoclast activity should be required. Bisphosphonates, as potent inhibitors of osteoclast function, reduce the morbidity of metastatic bone disease, decrease the prevalence of SREs, and improve control of bone pain. Molecular targeted agents which inhibit maturity and activity of osteoclast are under development, and some effectiveness has been proved in clinical trials. Long-term survival just like good control of a symptom is expected in future by using new drugs specific to bone metastasis as part of multidisciplinary approach. PMID:21358065

Taguchi, Tetsuya

2011-03-01

393

Mechanisms of Action and Therapeutic Potential of Strontium in Bone  

Microsoft Academic Search

The processes of bone resorption and formation are tightly governed by a variety of systemic and local regulatory agents. In addition, minerals and trace elements affect bone formation and resorption through direct or indirect effects on bone cells or bone mineral. Some trace elements closely chemically related to calcium, such as strontium (Sr), have pharmacological effects on bone when present

P. J. Marie; P. Ammann; G. Boivin; C. Rey

2001-01-01

394

The decrease in bone mass associated with aging and menopause  

Microsoft Academic Search

The human skeleton accumulates bone up to approximately age 30, after which bone is gradually lost. Although estrogen replacement therapy prevents postmenopausal bone loss, it is not certain that estrogen deficiency alone is responsible for the decrease in bone mass. Progesterone deficiency could also be a factor, and progesterone replacement therapy has been shown to prevent postmenopausal bone loss associated

Johan N. M. Heersche; Carlton G. Bellows; Yoichiro Ishida

1998-01-01

395

Periprosthetic Bone Remodelling in Total Knee Arthroplasty  

PubMed Central

ABSTRACT Introduction: The clinical studies have shown that the displacement of the prosthesis components, especially of the tibial one is higher during the first year, after which it reaches an equilibrum position compatible with a good long term functioning. This displacement takes place due to bone remodelling close to the implant secondary to different loading concentrations over different areas of bone. Material and Method: Our study implies a simulation on a computational model using the finite element analysis. The simulation started taking into account arbitrary points because of non-linear conditions of bone-prosthesis interface and it was iterative.. A hundred consecutive situations corresponding to intermediate bone remodelling phases have been calculated according to given loadings. Bone remodelling was appreciated as a function of time and bone density for each constitutive element of the computational model created by finite element method. For each constitutive element a medium value of stress during the walking cycle was applied. Results: Analyse of proximal epiphysis-prosthesis complex slices showed that bone density increase is maintained all over the stem in the immediately post-operative period. At 10 months, the moment considered to be the end of bone remodelling, areas with increased bone density are fewer and smaller. Meanwhile, their distribution with a concentration toward the internal compartment in the distal metaphysis is preserved. Conclusions: After the total knee arthroplasty the tibial bone suffered a process of remodelling adapted to the new stress conditions. This bone remodelling can influence, sometimes negatively, especially in the cases with tibial component varus malposition, the fixation, respectively the survival of the prosthesis. This process has been demonstrated both by clinical trials and by simulation, using the finite elements method of periprosthetic bone remodelling. PMID:25553127

GEORGEANU, Vlad; ATASIEI, Tudor; GRUIONU, Lucian

2014-01-01

396

Ultrasound of Primary Aneurysmal Bone Cyst  

PubMed Central

Aneurysmal bone cysts (ABC) are rare, benign, expansile lesions of bone often found in the metaphyses of long bones in pediatric and young adult population. Multiple fluid levels are typically seen on imaging with magnetic resonance imaging (MRI) or computed tomography (CT). We describe a case of a primary ABC in the fibula of a 34-year-old man diagnosed on ultrasound with a mobile fluid level demonstrated sonographically. PMID:24587935

Glazebrook, Katrina N.; Keeney, Gary L.; Rock, Michael G.

2014-01-01

397

Affective Disorders, Bone Metabolism, and Osteoporosis  

Microsoft Academic Search

The nature of the relationship between affective disorders, bone mineral density (BMD), and bone metabolism is unresolved,\\u000a although there is growing evidence that many medications used to treat affective disorders are associated with low BMD or\\u000a alterations in neuroendocrine systems that influence bone turnover. The objective of this review is to describe the current\\u000a evidence regarding the association of unipolar

Briana Mezuk

2008-01-01

398

Empirical Evaluation of Bone Extraction Protocols  

PubMed Central

The application of high-resolution analytical techniques to characterize ancient bone proteins requires clean, efficient extraction to obtain high quality data. Here, we evaluated many different protocols from the literature on ostrich cortical bone and moa cortical bone to evaluate their yield and relative purity using the identification of antibody-antigen complexes on enzyme-linked immunosorbent assay and gel electrophoresis. Moa bone provided an ancient comparison for the effectiveness of bone extraction protocols tested on ostrich bone. For the immunological part of this study, we focused on collagen I, osteocalcin, and hemoglobin because collagen and osteocalcin are the most abundant proteins in the mineralized extracellular matrix and hemoglobin is common in the vasculature. Most of these procedures demineralize the bone first, and then the remaining organics are chemically extracted. We found that the use of hydrochloric acid, rather than ethylenediaminetetraacetic acid, for demineralization resulted in the cleanest extractions because the acid was easily removed. In contrast, the use of ethylenediaminetetraacetic acid resulted in smearing upon electrophoretic separation, possibly indicating these samples were not as pure. The denaturing agents sodium dodecyl sulfate, urea, and guanidine HCl have been used extensively for the solubilization of proteins in non-biomineralized tissue, but only the latter has been used on bone. We show that all three denaturing agents are effective for extracting bone proteins. One additional method tested uses ammonium bicarbonate as a solubilizing buffer that is more appropriate for post-extraction analyses (e.g., proteomics) by removing the need for desalting. We found that both guanidine HCl and ammonium bicarbonate were effective for extracting many bone proteins, resulting in similar electrophoretic patterns. With the increasing use of proteomics, a new generation of scientists are now interested in the study of proteins from not only extant bone but also from ancient bone. PMID:22348088

Cleland, Timothy P.; Voegele, Kristyn; Schweitzer, Mary H.

2012-01-01

399

Calcium and bone metabolism during space flight  

NASA Technical Reports Server (NTRS)

Weightlessness induces bone loss. Understanding the nature of this loss and developing means to counteract it are significant challenges to potential human exploration missions. This article reviews the existing information from studies of bone and calcium metabolism conducted during space flight. It also highlights areas where nutrition may play a specific role in this bone loss, and where countermeasures may be developed to mitigate that loss.

Smith, Scott M.; Heer, Martina

2002-01-01

400

Homing of Cancer Cells to the Bone  

Microsoft Academic Search

A variety of tumor cells preferentially home to the bone. The homing of cancer cells to the bone represents a multi-step process\\u000a that involves malignant progression of the tumor, invasion of the tumor through the extracellular matrix and the blood vessels\\u000a and settling of the tumor cells in the bone. Gaining a greater understanding as to the mechanisms used by

Anjali Mishra; Yusuke Shiozawa; Kenneth J. Pienta; Russell S. Taichman

401

The biochemistry of ancient DNA in bone  

Microsoft Academic Search

The amount of DNA in ancient bone was determined by ethidium bromide staining after the removal of the potent Taq inhibitor, fulvic acid. A complete decalcification and a perfusion protocol were used to recover DNA from bone. A variety of purification techniques including molecular sieve, hydroxyapatite binding and ‘Magic’ preparations yielded DNA that spanned from 3.4?g\\/g of bone to below

N. Tuross

1994-01-01

402

The use of autoclaved cancellous bone  

Microsoft Academic Search

Summary  \\u000a Since transmission of HIV through allogenic bone grafts has been established, the concept of cryopreservation of allogenic\\u000a bone had to be reconsidered. The strict guidlines of the scientific board of the Bundesärztekammer of 1990 are very labour-,\\u000a time- and money-intensive. We have therefore moved to autoclaving allogenic cancellous bone. This is harvested from femoral\\u000a heads during THR in slices

E. H. Kuner; W. Schlickewei; M. Huber-Lang; D. J. Schaefer; J. Laubenberger

1998-01-01

403

Effects of glucan on bone marrow  

PubMed Central

Bone marrow damage represents a significant problem in cancer treatment. Therefore, it is clear that the pharmacologic protection against bone marrow damage is of considerable interest, since the development of novel and effective medical approaches to combat radiation or cytotoxic damage are of major importance not only to the medical field but also to several industries and the military. This review represents a summary of our knowledge of the effects of various glucans on bone marrow protection. PMID:25332994

Vannucci, Luca; Vetvicka, Vaclav

2014-01-01

404

Gravity, Calcium, And Bone: Update, 1989  

NASA Technical Reports Server (NTRS)

Report reviews short-term flight and ground-based experiments on effects of 1 g and 0 g on skeletal adaptation, calcium metabolism, and growth processes. Results indicate two principal components of calcium metabolism-calcium endocrine system and bone - respond within days to changes in orientation of body in gravitation and to weightlessness. Effects of spaceflight or bed rest on biomechanics of bones more severe than on total body bone mass.

Arnaud, Sara B.; Morey-Holton, Emily

1992-01-01

405

Method of adhering bone to a rigid substrate using a graphite fiber reinforced bone cement  

NASA Technical Reports Server (NTRS)

A method is described for adhering bone to the surface of a rigid substrate such as a metal or resin prosthesis using an improved surgical bone cement. The bone cement has mechanical properties more nearly matched to those of animal bone and thermal curing characteristics which result in less traumatization of body tissues and comprises a dispersion of short high modulus graphite fibers within a bonder composition including polymer dissolved in reactive monomer such as polymethylmethacrylate dissolved in methylmethacrylate monomer.

Knoell, A. C.; Maxwell, H. G. (inventors)

1977-01-01

406

Histologic and morphologic evaluation of explanted bone anchors from bone-anchored hearing aids  

Microsoft Academic Search

Bone-anchored hearing aids are a standard option in rehabilitation of patients with conductive or mixed hearing loss, and\\u000a also CROS fitting. However, the skin-penetrating bone anchor repeatedly gives reason for discussion about the risk of infection\\u000a of surrounding tissues as a major cause of malfunction. In the present study, explanted bone anchors with surrounding bone\\u000a and soft tissue were examined

Robert Mlynski; Eva Goldberg; Joerg Ebmeyer; Matthias Scheich; Stefan Gattenlöhner; Konrad Schwager; Rudolf Hagen; Wafaa Shehata-Dieler

2009-01-01

407

Changes in Bone Mass and Bone Turnover Following Distal Forearm Fracture  

Microsoft Academic Search

:   Bone loss occurs close to a fracture and is associated with increased bone turnover. Fracture healing itself results in increased\\u000a markers of bone turnover. But the exact patterns of these changes after different fractures are unclear. We aimed to investigate\\u000a the changes in bone density and biochemical markers following distal forearm fracture. Twenty women (mean age 63 years) were

B. M. Ingle; S. M. Hay; H. M. Bottjer; R. Eastell

1999-01-01

408

In Vitro and In Vivo effects of ipriflavone on bone formation and bone biomechanics  

Microsoft Academic Search

Ipriflavone (IP) positively affects bone density in postmenopausal osteoporosis, primarily by inhibiting bone resorption.\\u000a Using in vitro models of human osteoblast differentiation, we have observed that IP and some of its metabolites stimulate the expression\\u000a of bone sialoprotein, decorin, and type I collagen, and facilitate the deposition of mineralized matrix. This suggests that\\u000a IP may stimulate bone formation in addition

R. Civitelli

1997-01-01

409

A case of synovial sarcoma with bone metastasis identified by bone marrow scintigraphy  

SciTech Connect

In a patient with synovial sarcoma, routine bone survey showed no abnormality, while bone marrow scintigraphy with Tc-99m sulfur colloid revealed a defect in the fifth lumbar vertebra. At surgery, tumorous invasion was noted in the fifth lumbar vertebra and the surrounding tissues. It was suggested that the bone marrow scintigraphy was particularly useful in the detection of tumorous invasion into the bone marrow at the early stage before the destruction of skeletal tissue.

Otsuka, N.; Morita, R.; Yamamoto, T.; Muranaka, A.; Tomomitsu, T.; Yanagimoto, S.; Sone, T.; Fukunaga, M.

1985-04-01

410

Serum Bone Biomarkers and Oral\\/Systemic Bone Loss in Humans  

Microsoft Academic Search

We recently reported that subantimicrobial-dose doxycycline (SDD) significantly reduced serum bone-resorption biomarkers in subgroups of post-menopausal women. We hypothesize that changes in serum bone biomarkers are associated not only with systemic bone mineral density (BMD) changes, but also with alveolar bone changes over time. One hundred twenty-eight eligible post-menopausal women with periodontitis and systemic osteopenia were randomly assigned to receive

J. B. Payne; J. A. Stoner; H.-M. Lee; P. V. Nummikoski; R. A. Reinhardt; L. M. Golub

2011-01-01

411

Does xenogeneic demineralized bone matrix have clinical utility as a bone graft substitute?  

Microsoft Academic Search

Autologous bone harvested from the iliac crest is a commonly used grafting material for a number of surgical procedures; however, there is documented morbidity associated with secondary site harvesting. Because demineralized bone matrix (1313M) is inherently osteoinductive (i.e., it facilitates differentiation of uncommitted connective tissue cells into bone-forming cells), it has potential appeal as a bone-graft substitute. Allogeneic DBM usage

J. E. Block; J. Poser

1995-01-01

412

Bone tumor mimickers: A pictorial essay  

PubMed Central

Focal lesions in bone are very common and many of these lesions are not bone tumors. These bone tumor mimickers can include numerous normal anatomic variants and non-neoplastic processes. Many of these tumor mimickers can be left alone, while others can be due to a significant disease process. It is important for the radiologist and clinician to be aware of these bone tumor mimickers and understand the characteristic features which allow discrimination between them and true neoplasms in order to avoid unnecessary additional workup. Knowing which lesions to leave alone or which ones require workup can prevent misdiagnosis and reduce patient anxiety. PMID:25114385

Mhuircheartaigh, Jennifer Ni; Lin, Yu-Ching; Wu, Jim S

2014-01-01

413

Bone disease in pediatric idiopathic hypercalciuria  

PubMed Central

Idiopathic hypercalciuria (IH) is the leading metabolic risk factor for urolithiasis and affects all age groups without gender or race predominance. IH has a high morbidity with or without lithiasis and reduced bone mineral density (BMD), as described previously in pediatric patients as well as in adults. The pathogenesis of IH is complex and not completely understood, given that urinary excretion of calcium is the end result of an interplay between three organs (gut, bone and kidney), which is further orchestrated by hormones, such as 1,25 dihydroxyvitamin D, parathyroid hormone, calcitonin and fosfatonins (i.e., fibroblast growth-factor-23). Usually, a primary defect in one organ induces compensatory mechanisms in the remaining two organs, such as increased absorption of calcium in the gut secondary to a primary renal loss. Thus, IH is a systemic abnormality of calcium homeostasis with changes in cellular transport of this ion in intestines, kidneys and bones. Reduced BMD has been demonstrated in pediatric patients diagnosed with IH. However, the precise mechanisms of bone loss or failure of adequate bone mass gain are still unknown. The largest accumulation of bone mass occurs during childhood and adolescence, peaking at the end of the second decade of life. This accumulation should occur without interference to achieve the peak of optimal bone mass. Any interference may be a risk factor for the reduction of bone mass with increased risk of fractures in adulthood. This review will address the pathogenesis of IH and its consequence in bone mass. PMID:24175242

Moreira Guimarães Penido, Maria Goretti; de Sousa Tavares, Marcelo

2012-01-01

414

Dexamethsone suppresses bone formation via the osteoclast.  

PubMed

Glucocorticoids are central to treating inflammatory and immune disorders. These steroids, however, profoundly impact the skeleton, particularly when administered for prolonged periods. In fact, high-dose glucocorticoid therapy is almost universally associated with bone loss, prompting among the most common forms of crippling osteoporosis. Despite the frequency and severity of glucocorticoid-induced osteoporosis, its treatment is less than satisfactory, suggesting that its pathogenesis is incompletely understood. Net bone mass represents the relative activities of osteoblasts and osteoclasts and there is little question that glucocorticoids suppress the bone-forming cells, in vivo, via a process involving accelerated apoptosis (Weinstein 2001; Weinstein, Jilka, Parfitt, et al. 1998). Surprisingly, however, addition of glucocorticoids to cultures of osteoprogenitor cells actually increases their capacity to form mineralized bone nodules (Aubin 1999; Purpura, Aubin, and Zandstra 2004). This paradox raises the possibility that glucocorticoid suppression of bone formation, in vivo, reflects, at least in part, the steroid's targeting intermediary cells, which in turn inhibit the osteoblast. Bone remodeling is an ever-occuring event in mammals which is characterized by tethering of osteoclast and osteoblast function. The process is initiated by osteoclasts (OCs) resorbing a packet of bone, which in turn leads to osteoblasts being recruited to the site of resorption. This process establishes that osteoclastic bone resorption, in some manner, promotes osteoblastic bone formation at the same location. Consequently, pathologically or pharmacologically inhibited resorption eventuates in arrested osteoblast activity. PMID:17966386

Kim, Hyun-Ju; Zhao, Haibo; Kitaura, Hideki; Bhattacharyya, Sandip; Brewer, Judson A; Muglia, Louis J; Ross, F Patrick; Teitelbaum, Steven L

2007-01-01

415

Periprosthetic bone loss: diagnostic and therapeutic approaches  

PubMed Central

Total joint replacement surgery is being performed on an increasingly large part of the population. Clinical longevity of implants depends on their osseointegration, which is influenced by the load, the characteristics of the implant and the bone-implant interface, as well as by the quality and quantity of the surrounding bone. Aseptic loosening due to periprosthetic osteolysis is the most frequent known cause of implant failure. Wear of prosthetic materials results in the formation of numerous particles of debris that cause a complex biological response. Dual-energy X-ray Absorptiometry (DXA) is regarded as an accurate method to evaluate Bone Mineral Density (BMD) around hip or knee prostheses. Further data may be provided by a new device, the Bone Microarchitecture Analysis (BMA), which combines bone microarchitecture quantification and ultra high resolution osteo-articular imaging. Pharmacological strategies have been developed to prevent bone mass loss and to extend implant survival. Numerous trials with bisphosphonates show a protective effect on periprosthetic bone mass, up to 72 months after arthroplasty. Strontium ranelate has been demonstrated to increase the osseointegration of titanium implants in treated animals with improvement of bone microarchitecture and bone biomaterial properties.

Cavalli, Loredana; Brandi, Maria Luisa

2014-01-01

416

Bone Adaptation and Regeneration - New Developments  

NASA Astrophysics Data System (ADS)

Bone is a dynamic tissue that is constantly renewed and adapts to its local loading environment. Mechanical loading results in adaptive changes in bone size and shape that strengthen bone structure. The mechanisms for adaptation involve a multistep process called mechanotransduction, which is the ability of resident bone cells to perceive and translate mechanical energy into a cascade of structural and biochemical changes within the cells. The transduction of a mechanical signal to a biochemical response involves pathways within the cell membrane and cytoskeleton of the osteocytes, the professional mechansensor cells of bone. During the last decade the role of mechanosensitive osteocytes in bone metabolism and turnover, and the lacuno-canalicular porosity as the structure that mediates mechanosensing, is likely to reveal a new paradigm for understanding the bone formation response to mechanical loading, and the bone resorption response to disuse. Strain-derived fluid flow of interstitial fluid through the lacuno-canalicular porosity seems to mechanically activate the osteocytes, as well as ensures transport of cell signaling molecules, nutrients and waste products. Cell-cell signaling from the osteocyte sensor cells to the effector cells (osteoblasts or osteoclasts), and the effector cell response - either bone formation or resorption, allow an explanation of local bone gain and loss as well as remodeling in response to fatigue damage as processes supervised by mechanosensitive osteocytes. The osteogenic activity of cultured bone cells has been quantitatively correlated with varying stress stimulations highlighting the importance of the rate of loading. Theoretically a possible mechanism for the stress response by osteocytes is due to strain amplification at the pericellular matrix. Single cell studies on molecular responses of osteocytes provide insight on local architectural alignment in bone during remodeling. Alignment seems to occur as a result of the osteocytes sensing different canalicular flow patterns around cutting cone and reversal zone during loading, thus determining the bone's structure. Disturbances in architecture and permeability of the 3D porous network will affect transduction of mechanical loads to the mechanosensors. Uncovering the cellular and mechanical basis of the osteocyte's response to loading represents a significant challenge to our understanding of cellular mechanotransduction and bone remodeling. In view of the importance of mechanical stress for maintaining bone strength, mechanical stimuli have great potential for providing a therapeutic approach for bone (re)generation.

Klein-Nulend, Jenneke; Bacabac, Rommel Gaud

417

Machining cancellous bone prior to prosthetic implantation  

NASA Astrophysics Data System (ADS)

The structure of cancellous bone can be described as heterogeneous, and as such, is difficult to shape by cutting tools during clinical surgical practices. The structure of bone can have a devastating effect on the performance of the cutting tool unless it is coated with a hard-wearing, thin solid film. Here, the use of diamond-coated cutting tools to prepare bone for biomedical implants are investigated. This paper describes developments in the use of coated cutting tools for machining of cancellous bone and to prepare a nanostructured surface.

Jackson, M. J.; Robinson, G. M.; Sein, H.; Ahmed, W.; Woodwards, R.

2005-06-01

418

Prevent and cure disuse bone loss  

NASA Technical Reports Server (NTRS)

Anabolic agents like parathyroid hormone and postagladin E-like substances were studied in dogs and rats to determine their effectiveness in the prevention and cure of bone loss due to immobilization. It was determined that postagladin E2 administration prevented immobilization while at the same time it added extra bone in a dose responsive manner. Although bone mass returns, poor trabecular architecture remains after normal ambulation recovery from immobilization. Disuse related bone loss and poor trabecular architecture were cured by post-immobilization postagladin E2 treatment.

Jee, Webster S. S.

1994-01-01

419

Stresses in ultrasonically assisted bone cutting  

NASA Astrophysics Data System (ADS)

Bone cutting is a frequently used procedure in the orthopaedic surgery. Modern cutting techniques, such as ultrasonic assisted drilling, enable surgeons to perform precision operations in facial and spinal surgeries. Advanced understanding of the mechanics of bone cutting assisted by ultrasonic vibration is required to minimise bone fractures and to optimise the technique performance. The paper presents results of finite element simulations on ultrasonic and conventional bone cutting analysing the effects of ultrasonic vibration on cutting forces and stress distribution. The developed model is used to study the effects of cutting and vibration parameters (e.g. amplitude and frequency) on the stress distributions in the cutting region.

Alam, K.; Mitrofanov, A. V.; Bäker, M.; Silberschmidt, V. V.

2009-08-01

420

Bone regeneration: current concepts and future directions  

PubMed Central

Bone regeneration is a complex, well-orchestrated physiological process of bone formation, which can be seen during normal fracture healing, and is involved in continuous remodelling throughout adult life. However, there are complex clinical conditions in which bone regeneration is required in large quantity, such as for skeletal reconstruction of large bone defects created by trauma, infection, tumour resection and skeletal abnormalities, or cases in which the regenerative process is compromised, including avascular necrosis, atrophic non-unions and osteoporosis. Currently, there is a plethora of different strategies to augment the impaired or 'insufficient' bone-regeneration process, including the 'gold standard' autologous bone graft, free fibula vascularised graft, allograft implantation, and use of growth factors, osteoconductive scaffolds, osteoprogenitor cells and distraction osteogenesis. Improved 'local' strategies in terms of tissue engineering and gene therapy, or even 'systemic' enhancement of bone repair, are under intense investigation, in an effort to overcome the limitations of the current methods, to produce bone-graft substitutes with biomechanical properties that are as identical to normal bone as possible, to accelerate the overall regeneration process, or even to address systemic conditions, such as skeletal disorders and osteoporosis. PMID:21627784

2011-01-01

421

Bone mineral density, Bone mineral contents, MMP-8 and MMP-9 levels in Human Mandible and alveolar bone: Simulated microgravity  

NASA Astrophysics Data System (ADS)

Exposure to microgravity has been associated with several physiological changes in astronauts and cosmonauts, including an osteoporosis-like loss of bone mass. It has been reported that head-down tilt bed-rest studies mimic many of the observations seen in flights. There is no study on the correlation on effects of mandibular bone and alveolar bone loss in both sex in simulating microgravity. This study was designed to determine the Bone mineral density and GCF MMP-8 MMP-9 in normal healthy subject of both sexes in simulated microgravity condition of -6 head-down-tilt (HDT) bed rest. The subjects of this investigation were 10 male and 10 female volunteers participated in three weeks 6 HDT bed-rest exposure. The Bone density and bone mineral contents were measured by dual energy X-ray absorptiometry before and in simulated microgravity. The GCF MMP-8 MMP-8 were measured by Enzyme-linked immunosorbent assays (Human Quantikine MMP-8,-9 ELISA kit). The bone mineral density and bone mineral contents levels were significantly decreased in simulated microgravity condition in both genders, although insignificantly loss was higher in females as compared to males. MMP-8 MMP-9 levels were significantly increased in simulated microgravity as compared to normal condition although insignificantly higher in females as compared to males. Further study is required on large samples size including all factors effecting in simulated microgravity and microgravity. Keys words-Simulated microgravity condition, head-down-tilt, Bone loss, MMP-8, MMP-9, Bone density, Bone mineral contents.

Rai, Balwant; Kaur, Jasdeep; Catalina, Maria

422

Human Placenta-Derived Adherent Cells Prevent Bone loss, Stimulate Bone formation, and Suppress Growth of Multiple Myeloma in Bone  

PubMed Central

Human placenta has emerged as a valuable source of transplantable cells of mesenchymal and hematopoietic origin for multiple cytotherapeutic purposes, including enhanced engraftment of hematopoietic stem cells, modulation of inflammation, bone repair, and cancer. Placenta-derived adherent cells (PDACs) are mesenchymal-like stem cells isolated from postpartum human placenta. Multiple myeloma is closely associated with induction of bone disease and large lytic lesions, which are often not repaired and are usually the sites of relapses. We evaluated the antimyeloma therapeutic potential, in vivo survival, and trafficking of PDACs in the severe combined immunodeficiency (SCID)–rab model of medullary myeloma-associated bone loss. Intrabone injection of PDACs into non-myelomatous and myelomatous implanted bone in SCID-rab mice promoted bone formation by stimulating endogenous osteoblastogenesis, and most PDACs disappeared from bone within 4 weeks. PDACs inhibitory effects on myeloma bone disease and tumor growth were dose-dependent and comparable with those of fetal human mesenchymal stem cells (MSCs). Intrabone, but not subcutaneous, engraftment of PDACs inhibited bone disease and tumor growth in SCID-rab mice. Intratumor injection of PDACs had no effect on subcutaneous growth of myeloma cells. A small number of intravenously injected PDACs trafficked into myelomatous bone. Myeloma cell growth rate in vitro was lower in coculture with PDACs than with MSCs from human fetal bone or myeloma patients. PDACs also promoted apoptosis in osteoclast precursors and inhibited their differentiation. This study suggests that altering the bone marrow microenvironment with PDAC cytotherapy attenuates growth of myeloma and that PDAC cytotherapy is a promising therapeutic approach for myeloma osteolysis. PMID:21732484

Li, Xin; Ling, Wen; Pennisi, Angela; Wang, Yuping; Khan, Sharmin; Heidaran, Mohammad; Pal, Ajai; Zhang, Xiaokui; He, Shuyang; Zeitlin, Andy; Abbot, Stewart; Faleck, Herbert; Hariri, Robert; Shaughnessy, John D.; van Rhee, Frits; Nair, Bijay; Barlogie, Bart; Epstein, Joshua; Yaccoby, Shmuel

2011-01-01

423

Imaging of bone infection with labelled white blood cells role of contemporaneous bone marrow imaging  

Microsoft Academic Search

The uptake of white blood cells (WBC) into normal bone marrow may lead to difficulty in detecting bone infection. Twenty-one patients in whom the WBC scan was equivocal or positive underwent a technetium 99m colloid scan to show the distribution of bone marrow. Six patients had a positive WBC scan, and in five of them a discordant colloid scan confirmed

A. D. King; A. M. Peters; A. W. J. Stuttle; J. P. Lavender

1990-01-01

424

Guided bone regeneration using demineralized allogenic bone matrix with calcium sulfate: case series  

PubMed Central

PURPOSE The purpose of this case series was to evaluate the effect of guided bone regeneration using demineralized allogenic bone matrix with calcium sulfate. MATERIALS AND METHODS Guided bone regeneration using Demineralized Allogenic Bone Matrix with Calcium Sulfate (AlloMatrix™, Wright. USA) was performed at the time of implant placement from February 2010 to April 2010. At the time of the second surgery, clinical evaluation of bone healing and histologic evaluation were performed. The study included 10 patients, and 23 implants were placed. The extent of bony defects around implants was determined by measuring the horizontal and vertical bone defects using a periodontal probe from the mesial, distal, buccal, and lingual sides and calculating the mean and standard deviation of these measurements. Wedge-shaped tissue samples were obtained from 3 patients and histologic examination was performed. RESULTS In clinical evaluation, it was observed that horizontal bone defects were completely healed with new bones, and in the vertical bone defect area, 15.1% of the original defect area remained. In 3 patients, histological tests were performed, and 16.7-41.7% new bone formation was confirmed. Bone graft materials slowly underwent resorption over time. CONCLUSION AlloMatrix™ is an allograft material that can be readily manipulated. It does not require the use of barrier membranes, and good bone regeneration can be achieved with time. PMID:23755343

Kim, Young-Kyun; Lee, Ji-Young; Lim, Seung-Chul

2013-01-01

425

Bone Forming Potential of An-Organic Bovine Bone Graft: A Cone Beam CT study  

PubMed Central

Purpose: An-organic bovine bone graft is a xenograft with the potential of bone formation. The aim of this study was to evaluate the bone density using cone beam computed tomography scans around functional endosseous implant in the region of both augmented maxillary sinus with the an-organic bovine bone graft and the alveolar bone over which the graft was placed to provide space for the implants. Materials and Methods: Sterile freeze dried bovine bone graft produced by National Tissue Bank, University Sains, Malaysia was used for stage-1 implant placement with maxillary sinus augmentation in a total of 19 subjects with 19 implants. The age of all subjects ranged between 40-60 years with a mean age 51±4.70. All subjects underwent a follow up CT scan using PlanmecaPromax 3D® Cone beam computed tomography scanner at the Radiology department, Hospital University Sains, Malaysia. The collected data was then analysed to evaluate bone density in Hounsfield Units using PlanmecaRomexis” Imaging Software 2.2® which is specialized accompanying software of the cone beam computed tomography machine. Results: There was bone formation seen at the site of the augmented sinus. A significant increase (p<0.005) in bone density was reported at the augmented site compared to the bone density of the existing alveolar bone. Conclusion: An-organic bovine bone graft is an osteoconductive material that can be used for the purpose of maxillary sinus augmentation. PMID:25654037

Rahman, Shaifulizan AB.; Alam, Mohammad Khursheed; Gillani, Syed Wasif

2014-01-01

426

University of Michigan study finds 'fertilizing' bone marrow helps answer why some cancers spread to bones  

Cancer.gov

University of Michigan researchers found that administering a common chemotherapy drug before bone tumors took root actually fertilized the bone marrow, enabling cancer cells, once introduced, to seed and grow more easily. The pre-clinical findings provide valuable insight as to why some cancers metastasize to bone, and could eventually result in new metastasis-prevention drugs.

427

Semi-quantitative interpretation of the bone scan in metabolic bone disease  

Microsoft Academic Search

Certain easily recognisable features are commonly seen in the bone scans of patients with metabolic bone disorders. Seven such features have been numerically graded by three independent observers in the scans of 100 patients with metabolic bone disease and of 50 control subjects. The total score for each patient is defined as the metabolic index. The mean metabolic index for

Ignac Fogelman; Dennis L. Citrin; John G. Turner; Ian D. Hay; Rodney G. Bessent; Iain T. Boyle

1979-01-01

428

Recognition of cortical bone resorption in metabolic bone disease in vivo  

Microsoft Academic Search

This is an outline of radiologic assessment of cortical bone resorption for improved diagnosis of metabolic bone diseases by simple radiographic means: microradioscopy and morphometry. The methodology permits separate assessment of endosteal, intracortical, and periosteal resorption and an evaluation of both the quantity and the quality of cortical bone.

H. E. Meema

1977-01-01

429

Bone mineral measurement from Apollo experiment M-078. [derangement of bone mineral metabolism in spacecrews  

NASA Technical Reports Server (NTRS)

Loss of mineral from bone during periods of immobilization, recumbency, or weightlessness is examined. This report describes the instrumentation, technique, and bone mineral changes observed preflight and postflight for the Apollo 14, 15, and 16 missions. The bone mineral changes documented during the Apollo Program are reviewed, and their relevance to future missions is discussed.

Vogel, J. M.; Rambaut, P. C.; Smith, M. C., Jr.

1974-01-01

430

Carbonic Anhydrase and Bone Remodeling: Sulfonamide Inhibition of Bone Resorption in Organ Culture  

Microsoft Academic Search

Five sulfonamide inhibitors of carbonic anhydrase inhibited parathyroid hormone-induced resorption of bone in organ culture. The relative activities of the sulfonamides as resorption inhibitors were such as to suggest the presence of a functional carbonic anhydrase system in bone linked to the mechanism of bone resorption.

Cedric Minkin; Joan M. Jennings

1972-01-01

431

Bioactive ceramics: the effect of surface reactivity on bone formation and bone cell function  

Microsoft Academic Search

Surface reactivity is one of the common characteristics of bone bioactive ceramics. It contributes to their bone bonding ability and their enhancing effect on bone tissue formation. During implantation, reactions occur at the material–tissue interface that lead to time-dependent changes in the surface characteristics of the implant material and the tissues at the interface. This review describes some of the

P Ducheyne; Q Qiu

1999-01-01

432

Apoptotic bone cells may be engulfed by osteoclasts during alveolar bone resorption in young rats  

Microsoft Academic Search

The alveolar bone is a suitable in vivo physiological model for the study of apoptosis and interactions of bone cells because it undergoes continuous, rapid and intense resorption\\/remodelling, during a long period of time, to accommodate the growing tooth germs. The intensity of alveolar bone resorption greatly enhances the chances of observing images of the extremely rapid events of apoptosis

F. Boabaid; P. S. Cerri; E. Katchburian

2001-01-01

433

Mechanotransduction in bone: do bone cells act as sensors of fluid flow?  

Microsoft Academic Search

When compact bone is subjected to bend- ing loads, interstitial fluid in the bone matrix flows away from regions of high compressive stress. The amount of interstitial fluid flow is strongly influenced by the loading rate in a dose-dependent fashion. We hypothesize that in- terstitial fluid flow affects bone formation, and we tested this hypothesis indirectly by measuring the effect

CHARLES H. TURNER; MARK R. FORWOOD; MARK W. OTTER

434

Histologic study of the bone adjacent to titanium bone screws used for mandibular fracture treatment  

Microsoft Academic Search

Purpose: Titanium miniplates have been widely used in mandibular fracture fixation because of their strength and excellent biocompatibility. However, the condition of the bone adjacent to titanium bone screws has not been clarified. This study histologically examined the bone-screw interface in patients treated for mandibular fractures. Patients and Materials: Specimens were obtained from 14 patients, and the undecalcified sections were

Hisanori Hirai; Akira Okumura; Masaaki Goto; Takeshi Katsuki

2001-01-01

435

Quantitative analysis of bone reactions to relative motions at implant-bone interfaces  

Microsoft Academic Search

Connective soft tissues at the interface between implants and bone, such as in human joint replacements, can endanger the stability of the implant fixation. The potential of an implant to generate interface bone resorption and form soft tissue depends on many variables, including mechanical ones. These mechanical factors can be expressed in terms of relative motions between bone and implant

H. H. Weinans; HWJ Huiskes; H. J. Grootenboer

1993-01-01

436

Immunohistochemistry and BrdU-LTR assay The procedures for bone and bone marrow section preparation, immunostaining  

E-print Network

Immunohistochemistry and BrdU-LTR assay The procedures for bone and bone marrow section preparation High-resolution X-rays (Faxitron MX-20) of bone and bone histomorphometry (OsteoMetrics, Inc.) were., Weissman, I. L. & Akashi, K. Identification of clonogenic common lymphoid progenitors in mouse bone marrow

Cai, Long

437

A quantification strategy for missing bone mass in case of osteolytic bone lesions  

SciTech Connect

Purpose: Most of the patients who died of breast cancer have developed bone metastases. To understand the pathogenesis of bone metastases and to analyze treatment response of different bone remodeling therapies, preclinical animal models are examined. In breast cancer, bone metastases are often bone destructive. To assess treatment response of bone remodeling therapies, the volumes of these lesions have to be determined during the therapy process. The manual delineation of missing structures, especially if large parts are missing, is very time-consuming and not reproducible. Reproducibility is highly important to have comparable results during the therapy process. Therefore, a computerized approach is needed. Also for the preclinical research, a reproducible measurement of the lesions is essential. Here, the authors present an automated segmentation method for the measurement of missing bone mass in a preclinical rat model with bone metastases in the hind leg bones based on 3D CT scans. Methods: The affected bone structure is compared to a healthy model. Since in this preclinical rat trial the metastasis only occurs on the right hind legs, which is assured by using vessel clips, the authors use the left body side as a healthy model. The left femur is segmented with a statistical shape model which is initialised using the automatically segmented medullary cavity. The left tibia and fibula are segmented using volume growing starting at the tibia medullary cavity and stopping at the femur boundary. Masked images of both segmentations are mirrored along the median plane and transferred manually to the position of the affected bone by rigid registration. Affected bone and healthy model are compared based on their gray values. If the gray value of a voxel indicates bone mass in the healthy model and no bone in the affected bone, this voxel is considered to be osteolytic. Results: The lesion segmentations complete the missing bone structures in a reasonable way. The mean ratiov{sub r}/v{sub m} of the reconstructed bone volume v{sub r} and the healthy model bone volume v{sub m} is 1.07, which indicates a good reconstruction of the modified bone. Conclusions: The qualitative and quantitative comparison of manual and semi-automated segmentation results have shown that comparing a modified bone structure with a healthy model can be used to identify and measure missing bone mass in a reproducible way.

Fränzle, Andrea, E-mail: a.fraenzle@dkfz.de; Giske, Kristina [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Bretschi, Maren; Bäuerle, Tobias [Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Hillengass, Jens [Department of Internal Medicine V, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany)] [Department of Internal Medicine V, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Bendl, Rolf [Medical Informatics, Heilbronn University, Max-Planck-Strasse 39, 74081 Heilbronn, Germany and Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Medical Informatics, Heilbronn University, Max-Planck-Strasse 39, 74081 Heilbronn, Germany and Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

2013-12-15

438

Liquid antibiotics in bone cement  

PubMed Central

Objectives The objective of this study was to compare the elution characteristics, antimicrobial activity and mechanical properties of antibiotic-loaded bone cement (ALBC) loaded with powdered antibiotic, powdered antibiotic with inert filler (xylitol), or liquid antibiotic, particularly focusing on vancomycin and amphotericin B. Methods Cement specimens loaded with 2 g of vancomycin or amphotericin B powder (powder group), 2 g of antibiotic powder and 2 g of xylitol (xylitol group) or 12 ml of antibiotic solution containing 2 g of antibiotic (liquid group) were tested. Results Vancomycin elution was enhanced by 234% in the liquid group and by 12% in the xylitol group compared with the powder group. Amphotericin B elution was enhanced by 265% in the liquid group and by 65% in the xylitol group compared with the powder group. Based on the disk-diffusion assay, the eluate samples of vancomycin-loaded ALBC of the liquid group exhibited a significantly larger inhibitory zone than samples of the powder or the xylitol group. Regarding the ALBCs loaded with amphotericin B, only the eluate samples of the liquid group exhibited a clear inhibitory zone, which was not observed in either the xylitol or the powder groups. The ultimate compressive strength was significantly reduced in specimens containing liquid antibiotics. Conclusions Adding vancomycin or amphotericin B antibiotic powder in distilled water before mixing with bone cement can significantly improve the efficiency of antibiotic release than can loading ALBC with the same dose of antibiotic powder. This simple and effective method for preparation of ALBCs can significantly improve the efficiency of antibiotic release in ALBCs. Cite this article: Bone Joint Res 2014;3:246–51. PMID:25104836

Chang, Y. H.; Tai, C. L.; Hsu, H. Y.; Hsieh, P. H.; Lee, M. S.; Ueng, S. W. N.

2014-01-01

439

Bone metastases in gastrointestinal cancer.  

PubMed

Colorectal (CRC) and gastroesophageal (GEC) cancers unusually spread to the bone. However, bone metastases (BM) are responsible for skeletal-related events (SREs) associated with an altered quality of life. Aiming to describe the characteristics and prognostic influence of BM from gastro-intestinal cancers, we performed a retrospective analysis of prospectively collected data in patients treated in our institution (1996-2006). 189 patients (5.5 %) developed BM: 79 with GEC and 110 with CRC. 57 patients had bone-exclusive metastases. In univariate analyses, the median time to BM occurrence was correlated with the primary tumour (PT) localisation, surgery, histology and TNM staging. However, in multivariate analyses, the occurrence delay was significantly shorter only for patients with GEC (HR 2.1), N1-2 status (HR 1.9), M1 status (HR 2.4), and epidermoid carcinoma (HR 6.0). Pain was the most frequent clinical sign leading to BM diagnosis (77.2 %). SRE occurred in 55 % of patients. Median overall survivals (OSs) of patients with CRC and GEC were 9.4 months [95 % confidence interval (95 % CI) 6.4-11.1] and 3.4 months (95 % CI 2.5-9.0), respectively. In univariate analyses, OS was correlated with PT surgery and NM staging, and the number of BM. In multivariate analyses, only the PT surgery and the number of BM remained correlated with OS. Our results suggest that there may be a subset of patients associated with a quicker development of BM. Given their higher risk of SRE, they could benefit from an early screening, calling for further prospective studies encompassing patients with and without BM. PMID:25381591

Portales, Fabienne; Thézenas, Simon; Samalin, Emmanuelle; Assenat, Eric; Mazard, Thibault; Ychou, Marc

2015-01-01

440

N-Q Dinosaur Bones  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Quincy is a tour guide at a museum of science and history. During a tour of the museum, he tells some visitors about a fossilized dinosaur bone that is...

441

Blocking antibody to the ?-subunit of FSH prevents bone loss by inhibiting bone resorption and stimulating bone synthesis  

PubMed Central

Low estrogen levels undoubtedly underlie menopausal bone thinning. However, rapid and profuse bone loss begins 3 y before the last menstrual period, when serum estrogen is relatively normal. We have shown that the pituitary hormone FSH, the levels of which are high during late perimenopause, directly stimulates bone resorption by osteoclasts. Here, we generated and characterized a polyclonal antibody to a 13-amino-acid-long peptide sequence within the receptor-binding domain of the FSH ?-subunit. We show that the FSH antibody binds FSH specifically and blocks its action on osteoclast formation in vitro. When injected into ovariectomized mice, the FSH antibody attenuates bone loss significantly not only by inhibiting bone resorption, but also by stimulating bone formation, a yet uncharacterized action of FSH that we report herein. Mesenchymal cells isolated from mice treated with the FSH antibody show greater osteoblast precursor colony counts, similarly to mesenchymal cells isolated from FSH receptor (FSHR)?/? mice. This suggests that FSH negatively regulates osteoblast number. We confirm that this action is mediated by signaling-efficient FSHRs present on mesenchymal stem cells. Overall, the data prompt the future development of an FSH-blocking agent as a means of uncoupling bone formation and bone resorption to a therapeutic advantage in humans. PMID:22908268

Zhu, Ling-Ling; Blair, Harry; Cao, Jay; Yuen, Tony; Latif, Rauf; Guo, Lida; Tourkova, Irina L.; Li, Jianhua; Davies, Terry F.; Sun, Li; Bian, Zhuan; Rosen, Clifford; Zallone, Alberta; New, Maria I.; Zaidi, Mone

2012-01-01

442

[Processing of ceramiclike xenogeneic bone and experimental study of its bone formation from composite graft combined with bone marrow].  

PubMed

Ceramiclike xenogeneic bone (CXB) was obtained from the fresh bone of pig ribs being treated by physical and chemical methods to deprive of its organic substance. The CXB possessed the same natural porous network system as that of the human. The CXB was cultured with the bone marrow stromal cells of rabit. When the marrow cells had integrated with the CXB, thus a new material was obtained. (CXB-BM), and was implanted sacro-spinal muscle of rabbit. The specimens were observed under phase microscope, light microscope and electronic scanning microscope. The results showed that: at the 2nd week after the implantation of CBX-BM composite material there began the new bone formation, and the rate of bone formation was increased with time. There was evident new bone formation after 24 weeks. The process of the new bone formation were quite similar to the composite graft of HAP red autogenous and marrow, but the former degraded faster and formed typical cancellous structure earlier. There was no new bone formation when CXB was implanted alone in the control. Both the mechanism of osteogenetic potential and its clinical application were discussed. PMID:10374603

Li, Y; Zeng, C; Wang, H

1998-03-01

443

Morphometric evidence for bone resorption and replacement in prostate cancer.  

PubMed

A series of 78 patients with metastatic bone disease from prostate cancer underwent iliac crest biopsy, enabling histomorphometric quantification of eroded bone surface and bone volume in both tumour-free and metastatic bone tissue. Eroded surfaces in tumour-free specimens were high in patients with active compared to stable disease but bone volume was maintained in both groups, whilst in bone surrounding micrometastases (n = 8) eroded surfaces were further increased and bone volume reduced. Eroded surfaces within metastases were greater still but were associated with increased bone volume due to replacement of the existing trabecular tissue with abnormal woven bone, giving an overall appearance of sclerosis. These results show that the effect of prostate cancer on bone tissue is complex, involving differential disturbance of bone formation and resorption within metastases, in bone surrounding tumour invasion and in the tumour-free skeleton. PMID:1873694

Clarke, N W; McClure, J; George, N J

1991-07-01

444

[Bone and Calcium Research Update 2015. Recent advances in clinical assessment of trabecular bone architecture : trabecular bone score (TBS)].  

PubMed

Although dual-energy X-ray absorptiometry (DXA) is regarded as the gold-standard technique for diagnosing osteoporosis, bone mineral density (BMD) alone by DXA is not sufficient for bone strength assessment. Trabecular bone score (TBS) is a texture analysis parameter that evaluates pixel gray-level variations in DXA images of the lumbar spine and allows to assess bone microarchitectural status that is one of the determinants of bone strength. Recent clinical evidences show that TBS is associated with fracture risk in primary and secondary osteoporosis, has a complementary role to lumbar spine BMD and responds to osteoporosis medications somewhat differently than BMD. Thus TBS has the potential to become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment. PMID:25530526

Sone, Teruki

2015-01-01

445

Auto-fluorescence of the bone and its use for delineation of bone necrosis.  

PubMed

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a challenging complication of long-term bisphosphonate treatment. Currently, the drawback in the surgical management of BRONJ is the difficulty distinguishing between viable and necrotic bone. Intraoperative bone fluorescence induced by tetracyclines has been shown to be a valuable aid to overcome this problem. In this technical note we report the finding that viable bone is auto-fluorescent using the VELscope Vx fluorescence lamp. Necrotic bone shows an altered fluorescence pattern (pale or no fluorescence). Thus it is suggested that auto-fluorescence of bone might be of similar use during the surgical therapy of BRONJ. PMID:25128260

Ristow, O; Pautke, C

2014-11-01

446

Effect of epimedium pubescen flavonoid on bone mineral status and bone turnover in male rats chronically exposed to cigarette smoke  

PubMed Central

Background Epimedii herba is one of the most frequently used herbs in formulas that are prescribed for the treatment of osteoporosis in China and its main constituent is Epimedium pubescen flavonoid (EPF). However, it is unclear whether EPF during chronic exposure to cigarette smoke may have a protective influence on the skeleton. The present study investigated the effect of EPF on bone mineral status and bone turnover in a rat model of human relatively high exposure to cigarette smoke. Methods Fifty male Wistar rats were randomized into five groups: controls, passive smoking groups and passive smoking rats administered EPF at three dosage levels (75, 150 or 300?mg/kg/day) in drinking water for 4?months. A rat model of passive smoking was prepared by breeding male rats in a cigarette-smoking box. Bone mineral content (BMC), bone mineral density (BMD), bone turnover markers, bone histomorphometric parameters and biomechanical properties were examined. Results Smoke exposure decreased BMC and BMD, increased bone turnover (inhibited bone formation and stimulated its resorption), affected bone histomorphometry (increased trabecular separation and osteoclast surface per bone surface; decreased trabecular bone volume, trabecular thickness, trabecular number, cortical thickness, bone formation rate and osteoblast surface per bone surface), and reduced mechanical properties. EPF supplementation during cigarette smoke exposure prevented smoke-induced changes in bone mineral status and bone turnover. Conclusion The results suggest that EPF can prevent the adverse effects of smoke exposure on bone by stimulating bone formation and inhibiting bone turnover and bone resorption. PMID:22713117

2012-01-01

447

New laboratory tools in the assessment of bone quality  

Microsoft Academic Search

Bone quality is a complex set of intricated and interdependent factors that influence bone strength. A number of methods have\\u000a emerged to measure bone quality, taking into account the organic or the mineral phase of the bone matrix, in the laboratory.\\u000a Bone quality is a complex set of different factors that are interdependent. The bone matrix organization can be described

D. Chappard; M. F. Baslé; E. Legrand; M. Audran

2011-01-01

448

Biomechanical testing of implant free wedge shaped bone block fixation for bone patellar tendon bone anterior cruciate ligament reconstruction in a bovine model  

Microsoft Academic Search

BACKGROUND: The use of an interference fit wedged bone plug to provide fixation in the tibial tunnel when using bone-patellar tendon-bone autograft for anterior cruciate ligament reconstruction offers many theoretic advantages including the potential to offer a more economical and biological alternative to screw fixation. This technique has not been subjected to biomechanical testing. We hypothesised that a wedged bone

Charles A Willis-Owen; Trevor C Hearn; Gregory C Keene; John J Costi

2010-01-01

449

Systemic zoledronate treatment both prevents resorption of allograft bone and increases the retention of new formed bone during revascularization and remodelling. A bone chamber study in rats  

Microsoft Academic Search

BACKGROUND: In osteonecrosis the vascular supply of the bone is interrupted and the living cells die. The inorganic mineral network remains intact until ingrowing blood vessels invade the graft. Accompanying osteoclasts start to resorb the bone trabeculae and gradually replace the bone. If the osteonecrosis occurs in mechanically loaded parts, like in the subchondral bone of a loaded joint, the

Jörgen Åstrand; Anna Kajsa Harding; Per Aspenberg; Magnus Tägil

2006-01-01

450

Histologic Comparison of Regenerate Bone Produced from Dentate Versus Edentulous Transport Discs in Bone Transport Distraction Osteogenesis  

E-print Network

Purpose: The purpose of this research was to quantify the number of blood vessels and nerves and mineral apposition rate (MAR) in native bone and compare it to the regenerate bone produced by bone transport distraction osteogenesis (BTDO...

Sevilla Gaitan, Carlos

2013-12-10

451

Bone marrow lesion volume reduction is not associated with improvement of other periarticular bone measures: data from the Osteoarthritis Initiative  

E-print Network

A: MRI-detected subchondral bone marrow signal alterationsMRI-detected subchondral bone marrow lesions is associatedmarrow lesion (BML) volume change and changes in periarticular bone mineral density (paBMD) as well as subchondral

2013-01-01

452

Aging changes in the bones - muscles - joints  

MedlinePLUS

... Bone mass or density is lost as people age, especially in women after menopause . The bones lose calcium and other minerals. ... genetically determined. Muscle changes often begin in the 20s in men and ... (an age-related pigment) and fat are deposited in muscle ...

453

Bone disorders in sickle-cell disease  

Microsoft Academic Search

Sickle cell disease involves many organs but musculo-skeletal problems present most often with bone pain, the most common reason for admission to hospital. Two separate pathological abnormalities cause these lesions. Sickling of the red cells produces thromboembolic infarcts in bone leading to pain, crises and sometimes osteomyelitis; increased destruction of sickle red cells produces haemolysis, an increase in erythroblastic activity

O. Onuba

1993-01-01

454

Dem Bones: Forensic Resurrection of a Skeleton.  

ERIC Educational Resources Information Center

Presents an activity for students to determine the sex and age of an individual from a collection of bones. Simulates some of the actual procedures conducted in a forensic anthropologist's lab, examining and identifying bones through a series of lab activities. (Author/ASK)

Bruce, Alease

2001-01-01

455

Incorporation and distribution of strontium in bone  

Microsoft Academic Search

The distribution and incorporation of strontium into bone has been examined in rats, monkeys, and humans after oral administration of strontium (either strontium chloride or strontium ranelate). After repeated administration for a sufficient period of time (at least 4 weeks in rats), strontium incorporation into bone reaches a plateau level. This plateau appears to be lower in females than in

S. G Dahl; P Allain; P. J Marie; Y Mauras; G Boivin; P Ammann; Y Tsouderos; P. D Delmas; C Christiansen

2001-01-01

456

[Osteoarticular involvement in parasitic diseases: bone treponematosis].  

PubMed

Bone and joint localizations of treponematosis vary greatly although there are many common features. Osteal and periosteal lesions are common. We report radiographic descriptions of bone and joint treponematosis, which must not go unrecognized due to the increasing incidence of these diseases. PMID:9846288

Arteaga, C; Gueguen, G E; Richez, P; Belliol, E; Baréa, D; Raillat, A; Salamand, P; Clavel, G; Briant, J F

1998-11-01

457

Hierarchical microimaging of bone structure and function  

Microsoft Academic Search

With recent advances in molecular medicine and disease treatment in osteoporosis, quantitative image processing of three-dimensional bone structures is critical in the context of bone quality assessment. Biomedical imaging technology such as MRI or CT is readily available, but few attempts have been made to expand the capabilities of these systems by integrating quantitative analysis tools and by exploring structure–function

Ralph Müller

2009-01-01

458

Multi-frequency axial transmission bone ultrasonometer.  

PubMed

The last decade has seen a surge in the development of axial transmission QUS (Quantitative UltraSound) technologies for the assessment of long bones using various modes of acoustic waves. The condition of cortical bones and the development of osteoporosis are determined by numerous mechanical, micro-structural, and geometrical or macro-structural bone properties like hardness, porosity and cortical thickness. Such complex manifestations of osteoporosis require the evaluation of multiple parameters with different sensitivities to the various properties of bone that are affected by the disease. This objective may be achieved by using a multi-frequency ultrasonic examination The ratio of the acoustic wavelength to the cortical thickness can be changed by varying the frequency of the ultrasonic pulse propagating through the long bone that results in the change in composition of the induced wave comprised of a set of numerous modes of guided, longitudinal, and surface acoustic waves. The multi-frequency axial transmission QUS method developed at Artann Laboratories (Trenton, NJ) is implemented in the Bone Ultrasonic Scanner (BUSS). In the current version of the BUSS, a train of ultrasonic pulses with 60, 100, 400, 800, and 1200 kHz frequencies is used. The developed technology was tested on a variety of bone phantoms simulating normal, osteopenic, and osteoporotic bones. The results of this study confirm the feasibility of the multi-frequency approach for the assessment of the processes leading to osteoporosis. PMID:24206675

Tatarinov, Alexey; Egorov, Vladimir; Sarvazyan, Noune; Sarvazyan, Armen

2014-07-01

459

Metabolic Bone Disease of Total Parenteral Nutrition  

Microsoft Academic Search

Parenteral nutrition-associated metabolic bone disease in children is manifested primarily as osteopenia and, on occasion, fractures. The etiology is likely multifactorial, with calcium and phosphate deficiency playing a major role in the preterm infant and with the role of aluminum toxicity yet to be clearly defined in this population. Lack of normal values of bone histomorphometry in the premature infant

Gordon L Klein

1998-01-01

460

Bone remodeling and silicon deficiency in rats  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alveolar bone undergoes continuous remodeling to meet physiologic and functional demands. The aim of the present work was to evaluate histologically and histomorphometrically the effect of silicon deficiency on bone modeling and remodeling in the periodontal cortical plate. Two groups of weaning mal...