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Fossil fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil and accumulate it in their mineral phase. In cortical parts of long bone diaphysis a fluorine concentration profile can be observed, which carries information on the exposure duration of the buried object in its shape. The distribution of fluorine in a sample however is strongly influenced by environmentally induced processes of bone diagenesis, i.e. alteration in the structure and composition of bone mineral and degradation of the organic components that may make the time information indistinct.

PIGE (Proton Induced Gamma-ray Emission) is a precise and fast analytical technique to determine the quantitative fluorine content and its distribution in cross sections of bone and tooth specimen non-destructively. The simultaneous detection of Ca by PIXE (Proton Induced X-ray Emission) provides additional information on the sample topography. Cracks, alteration haloes and the porosity, which is typical for human bone samples, are parameters which have direct influence on the fluorine uptake and transport during burial. This contribution outlines the combined approach of using PIGE and PIXE measurement to understand some aspects of the complex environmental impact that impedes exposure age dating by fluorine diffusion profiling.

A method of quantitative analysis of bone samples by simultaneous measurements of proton induced X-ray emission (PIXE) and Rutherford backscattered (RBS) spectra is described. The method is used for the evaluation of the data collected during proton microprobe irradiation. The RBS spectra are used for the determination of the sample thickness. The sample matrix is regarded as a mixture of collagen and hydroxyapatite. The unknown proportion of both compounds at each irradiated point is adjusted until the Ca concentration determined by PIXE is in accordance with the value calculated on the basis of the assumed matrix composition. For quantitative analysis, the calculation of the absolute yield using the thick target PIXE formula was applied. The sources and ranges of systematic errors are discussed.

A Standard-free method, which has been developed by ourselves, was applied to powdered biomedical samples to which a conventional method of quantitative analysis, such as an internal standard method, can not be successfully applied. First, NIST-Bovine liver and NIES-rice targets, which are powdered as they are, were analyzed by the standard-free method and correct quantitative values of potassium and manganese concentration, which are consistent with those obtained by the conventional internal standard method, were obtained. Furthermore, for relative values of concentration of various elements, almost the best results we have ever had were obtained. Next, the present method has been successfully applied to a hard tissue sample (mouse bone), which is quite difficult to be accurately analyzed by the internal standard method. In order to solve the problem of falling off of powdered samples from a backing film, a carbon tape with an adhesive agent has been examined and found to be quite effective.

Availability of a powdered internal standard method developed in the previous report has been investigated in detail for geological, mineralogical, environmental and biological samples. It is found that this method is effective for various powdered samples composed of high-Z elements. A computer program for correcting self-absorption of x-rays, which is based on the method we previously reported, was developed and it has been applied to soil samples of varied thickness. As a result, it is found that the method is quite effective even for a pretty thick target where particles overlap with each other. Moreover, the method was applied to several rock samples, which were prepared by grinding and consist of particles of divergent size, and found to be applicable. Lastly, the powdered internal standard method was applied to a biological sample and found to be almost satisfactory, too. These results demonstrate the availability of the powdered internal standard method combined with the method of x-ray-absorption correction for samples in many research fields.

The purpose of this study was to assess the effect of 18-week Tai Chi training on body balance in dynamic trial among elderly men. The study covered 49 subjects from age 60 to 82.1 years, who had osteopenia or osteoporosis. The subjects were recruited from the community by direct mailings and community efforts to participate in studies. The participants were randomly assigned to either the exercise intervention (n = 25) or control groups (n = 24). The Tai Chi group participated in an 18-week exercise class held for 45 min, twice a week. Body balance was assessed using a Computer Posturographic System PE 90 produced by the Military Institute of Aviation Medicine in Warsaw with modified software made in Pro-Med. During the measurement of body balance, the capacity to perform specific tasks was analyzed (deflections in the set scope and direction). In the Tai Chi group, an increase (p ≤ 0.01) in effectiveness of balance task performance was noted from 80.95% to 84.45% after the training. In the control group, no statistically significant improvement in the level of body balance was found in the same period. Thus, an 18-week period of Tai Chi exercises twice a week for 45 min is beneficial for dynamic balance. It can be important for reducing fall risk factors.

We investigated whether treatments with beta-blockers or other administrations that have similar actions to β-blockers, such as Chinese herbs or needling, were effective in treating osteoporosis induced by ovariectomy (OVX). Female Wister rats were divided into five groups: a sham-operated control group treated with vehicle (Sham, n = 8), an ovariectomized (OVX) group treated with vehicle (Model, n = 8), an OVX group administered with propranolol (Pro, n = 10), an OVX group administered an ethanol extract of Fructus Citri Sarcodactylis (Fcs, n = 9), and an OVX punctured at Sanyinjiao (SP-6) and Neiguan (PC-6) (Needling, n = 8). The treatment started when rats were 12 weeks old and continued for 24 weeks. Serum osteocalcin and urinary deoxypyridinoline (Dpd) levels were upregulated in rats in response to OVX, together with a significantly decreased BMD and trabecular bone area. The Pro, Fcs and Needling treatment improved the decreased BMD and the trabecular area, increased the trabecular number, lowered the trabecular separation to some extent as well as significantly depressed the urinary Dpd levels (p < 0.05). The bone formation markers, such as the mineralizing surface, mineral apposition rate and bone formation rate were not significantly changed, along with a slightly higher trend of osteocalcin levels when compared with the Model rats. The slower heart rate and lower plasma NE levels in these therapeutic groups were also found. Our results suggested that propranolol, Fcs and needling on Sanyinjiao (SP-6) and Neiguan (PC-6) may improve the bone mass of OVX rats, and it provides an alternative and potential therapy for the prevention of postmenopausal osteoporosis.

To understand the physiology and pathology of human skeletal system, the accurate measurement of microscopic biomechanical properties of bone is an important works. In this study, a measurement system of the Poisson's ratio with a sub-nano resolution was developed. The resulting resolution of the system was 0.3 nm, which was 0.1% of the measurement error for this system configuration. Using this measurement system, actual tests were performed to check the capability of the measurement system. Cubic bone specimens with a dimension of 300 μm were loaded up to an axial strain of 0.5%, which is within the elastic range of the specimens. The mean elastic modulus and the Poisson's ratio of bovine femoral cortical bone measured in this study were 14.42 GPa (SD ± 0.6179) and 0.265 (SD ± 0.0125) respectively. The developed system will be useful to understand the biomechanics of bones for modeling the mechanobiological bone system.

The regulatory influence of the parathyroid hormone (PTH) is exerted on bone, which serves as a vital reservoir of calcium within the body. While various aspects of bone growth, turnover, and mechanisms operate independently of gonadal hormones, a crucial role is assumed by sex steroids, particularly estrogen, in maintaining bone equilibrium in adults. In order to unravel the underlying mechanisms of bone remodeling mediated by PTH, a distinguished mathematical model of this intricate process is presented. Subsequently, the temporal effects of Plasma PTH and PTH external dosages are investigated using the proposed mathematical model. Among the limited repertoire of approved and accessible anabolic treatments for severe osteoporosis, daily injections of PTH stand out. This pharmaceutical marvel possesses a unique dual action, capable of acting either anabolically or catabolically, contingent upon the mode of administration. The study aims to accurately predict osteogenic responses to introduced and endogenous PTH, incorporating factors such as $TGF$-$\beta$, $RANKL$, and bisphosphonates in osteoblast–osteoclast signaling, as well as considering PTH’s influence on the gland and the regulatory roles of $Run{x}_2$, $pCREB$, and $Bc{l}_2$ in osteoblast apoptosis and bone volume effects. Through diverse methods including illustrative depictions, numerical simulations, sensitivity analysis, and stability analysis, this work seeks to comprehend how PTH therapy impacts bone volume, enhancing its therapeutic relevance.

We evaluated rat bone viability using a bone viability index (BVI). To evaluate hypothermic ischaemic bone injury, 21 amputated hind limbs of Fischer rats were preserved at hypothermia (4°C) for 1, 3 and 6 hours. To evaluate hypothermic ischaemia/reperfusion injury, another 28 amputated limbs were transplanted to recipient rats after hypothermic ischaemia for 3 and 6 hours, respectively. Total RNA isolated from each tibia was fractionated by electrophoresis and hybridised with ³²P-labelled cDNA of GAPDH, and the radioactivity of intact and degraded GAPDH mRNA measured. BVI was calculated as follows, BVI = {A / (A + B)} × 100, where A and B represent the radioactivities corresponding to intact and degraded GAPDH mRNA bands, respectively. In the hypothermic ischaemic insult group, BVIs were comparable to those of controls. However, in the 3-hour hypothermic ischaemia/reperfusion group, BVI was lower than that of the controls. Likewise, there was a significant difference between the 6-hour ischaemia/reperfusion group and controls. These results showed that bone viability decreased even after just a 3-hour hypothermic ischaemia/reperfusion.

Benign fibrous histiocytoma (BFH) of the bone is a rare benign lesion characterised by the presence of fibroblasts and histiocytes. Fibrohistocytic lesions involving bone with identical histological appearances are common during childhood such as fibrous cortical defect. However, BFH is very rare and can only be differentially diagnosed with its presentation, localisation and radiologic features. Here we describe a 33-year-old man with BFH in a rare location, a phalanx. To our knowledge this is the second reported case of a BFH involving the proximal phalanx of the thumb in an adult. We report clinical, radiologic and histological findings of the case and briefly review the literature on the subject.

The purpose of this study was to assess vascularity of the lunate by number of foramina and radiography of vessels of the wrist. The genesis of lunatomalacia requires some vascular risk and mechanical predisposition. The findings were correlated with the cause of Kienböck's disease. The vascular foramina were more than two in 91.33% of the lunate. The lunate had consistent dorsal and palmar branches from radial artery. The additional branches from anterior interosseous artery in 72.22% and a branch of palmar inter carpal arch in 69.44% cases contributed in arterial anastomosis on palmar aspect of lunate. The dorsal blood supply was found by anterior interosseous artery in 85.71% of specimens and dorsal branch from dorsal intercarpal arch in 50% of specimens. The blood supply of lunate comes along with various ligaments which may be disrupted due to trauma or strain leading to avascular necrosis. The present observations are suggestive of rich blood supply of lunate in comparison of other investigations. Therefore Kienböck's disease is less common in northern India.

We report a novel method of debridement for penetrating trauma to the hand involving bone using a sterile hand drill. This provides a means for adequate clearance of debris which may otherwise be left in-situ due to poor access to the contaminants when conventional techniques of debridement are used.

A case of ossified median nerve schwannoma in the left arm, first noticed about 40 years ago is examined. Although calcification of old schwannoma is sometimes seen, new bone formation in a schwannoma is extremely rare. Since there was a strong adhesion between the tumour and the median nerve in this case, the tumour could not be enucleated easily. The tumour was excised under a surgical microscopy without any neurological deficit.

Purpose: To determine the rate of antibiotic elution from tobramycin-impregnated ProOsteon (Interpore) and Collagraft (Zimmer). Methods: Five samples of Collagraft and ProOsteon were impregnated with a solution containing 1.2 g of tobramycin and 10 ml of sterile water. The samples were then allowed to dry overnight. These samples were stored at 37°C in separate test tubes containing phosphate buffered saline (PBS). The solution in each test tube was removed with a pipette at hours 3, 6, 9 and 12 and days 1, 2, 3, 5, 7, 9, 11 and 13. The PBS was then replaced. The pipetted solution was sent for laboratory quantification and also used in a bioassay to determine antibiotic level. To serve as a control, two additional samples of each bone graft that were not impregnated with antibiotic were placed in separate test tubes and subjected to the same protocol. Results: The antibiotic elution rate for both ProOsteon and Collagraft was high at 3 hours [5362 and 4875 μg/ml on day 3 (3.1 μg/ml) for the Collagraft and day 7 (3.7 μg/ml) for the ProOsteon]. Effective intravenous tobramycin level is considered to be 4–6 μg/ml. Conclusion: Bone graft substitute can be used as a delivery vehicle for tobramycin. In addition, antibiotic-impregnated synthetic bone graft may potentially fill a dead space or cavitary defect without the need for large autologous grafts and does not require later removal.

The purpose of this study is to investigate the effects of normal, moderate and high doses of fluoride on rat epipyseal growth plate and surrounding bone, and to compare it with controls. In order to achieve this, 80 rats were divided into five groups (n: 16/group) and treated with 0, 1.2, 3, 50 and 100 ppm fluoridated water since birth (Groups I to V, respectively). Four rats from each group were sacrificed at 6th, 9th, 12th and 16th weeks for radiological and histopathological examinations.

There was no significant variation on programmed cell death of cartilagenous components of the growth plate and chondroid matrix histopathologically between control group and fluoride-treated groups. But, minimal irregularities on the cartilage septum of primary spongiosa were detected in one rat from Group IV and one from Group V. The main histopathologic findings of the rats which were treated with high doses of fluoride were irregular lamella, variation in calcium content, minimally enlarged Haversian canals, focal osteoblastic proliferation, rare zones of woven bone on the diaphyseal cortical bone and secondary spongiosa, increase in ossicle size and minimal focal osteoblastic proliferation on the secondary ossification center. The only consistent radiological finding was relative widening and late partial fusing of the epiphyseal growth plates of high-dose treated groups at 16th week.

As a result, high doses of fluoride did not directly affect chondrocyte morphology of growth plate on young rats. More sophisticated techniques would be beneficial for further investigations on this subject.

The effect of aging on long bone mechanical properties and bone formative capacity was characterized in the male Fisher 344 rat. The femurs of rats from three age groups (4 mo., 12 mo. and 28 mo.) were tested in three-point bending to determine their structural properties. The apparent material properties were then calculated by adjusting for bone geometry. Bone formation was assessed by dynamic histomorphometry of both cortical and cancellous bone as well as by Northern blot analysis for the expression of the osteoblast phenotypic proteins osteopontin (OP), osteocalcin (OC), type I collagen (COL) and alkaline phosphatase (AP). Aging resulted in a decline in the apparent material properties that was associated with a compensatory alteration of bone geometry that preserved structural strength and stiffness. Histomorphometric analysis revealed significant age-related decreases in cancellous bone volume, trabecular number and increased trabecular separation suggesting the existence of senile osteopenia in the proximal tibia of the male Fisher 344 rat. A significant decline in bone formation rate (BFR), but not mineral apposition rate, suggests that a reduction in osteoblast number, but not osteoblast activity, contributes to age-related bone loss. The decline in BFR with aging was reflected in a decreased mRNA expression for OP, OC and COL but not AP. Further, the pattern of mRNA expression was consistent with reduced osteoblast differentiation with aging. The present study indicates the age-related decline in material properties of long bones is paralleled by a decrease in osteogenesis.

Based on the pharmaco-physiology of the aminobisphosphonates, it could be speculated that bisphosphonates could induce not only the osteopetrotic bone disease because of their selective suppression of osteoclastic activity, but also could affect directly or indirectly the endocrine system, local factors, and also the bone metabolic turnover. Consequently, the bone fragility could be rather produced by long-term aminobisphosphonate therapy. Bisphosphonate-mediated bone disease was labeled by Odvina et al. in 2005 [Odvina CV, Zerwerth JE, Rao DS et al. Severely suppressed bone turnover; a potential complication of alendronate therapy. J Clin Endocrinol Metab90: 1294–1301, 2005.] as the "severely suppressed bone turnover (SSBT)" on the metabolic turnover basis. However, such definition could contain various drug-induced bone diseases, and did not indicate any particular condition, induced by the bisphosphonate. The term "SSBT" is thought not solely to be based on its histology, and seems rather a clinical term applicable to the various drug-induced bone diseases. Therefore, the current authors attempted to characterize the bisphosphonate-mediated bone disease on the basis of the combined image and histological studies, and finally concluded that the prolonged bisphosphonate therapy could produce an atypical osteomalacic bone disease. (osteosclerosis of osteomalacia) which leads to fragility fracture. It is puzzling as to why malacia rather than petrosis develops in the skeleton.

Background: Surgical techniques for resection of tumors at proximal humerus and scapula has been described in literature along with different classification systems, however, these techniques have not been revised for a while and the classification systems which are currently in use neither respect the difference between bone and soft tissue tumors nor the anatomical location humeral vs scapular. Material and Methods: The author operated on 32 patients with shoulder girdle tumors, all are bone tumors, Ewings sarcoma ($n=14$), Osteosarcoma ($n=6$), Metastatic tumors ($n=6$), GCT ($n=3$), Chondrosarcoma ($n=3$). We assigned two separate classifications to humerus and scapula resection, since surgical approaches, techniques, and reconstruction options are totally different for the both sites. Resection of the humerus is classified into: Type I to Type IV, A: is added to the type when the majority of Deltoid is preserved, and B: when it is sacrificed. And we classify the scapula resection into: Type I to Type III, A: is added to the type when the majority of Deltoid is preserved, and B: when it is sacrificed. In extra articular humerus resection, we found that sacrificing the acromion and coracoid process is not necessary as part of routine resection. Preservation of these structures can improve the cosmetic appearance of the shoulder with at least equal functional outcome. Endoprosthesis was used in 26 patients for reconstruction, osteoarticular allograft was used in 2 patients, and Tichoff Lindberg technique for 4 patients. Results: At 30 month mean follow up period, 2 patients developed local recurrence (osteosarcoma $n=1$, Ewing Sarcoma $n=1$), 2 patients had wound infection, and one patient developed stem loosening. The average MSTS functional score for all patients was 83%. Conclusion: The modification of surgical techniques saved structures which were unnecessarily resected, and kept the integrity of muscles and their attachments which were sacrificed in previously described techniques. This might lead to fewer restrictions during the rehabilitation process and resulted in preservation of the shoulder contour. The new classification system is realistic, separates the humeral resection from the scapular one, easy to be recalled and applicable to all patients.

Cigarette smoking is regarded as a risk factor for developing complications in fracture healing. To determine whether nicotine would retard fracture healing in the rat, 25 rats were divided into two groups and given nicotine or saline subcutaneously at a dose of 2 mg/kg a day, for four weeks. Then their right forelimbs were broken. The rats were killed and histopathologic sections of the radius and ulna were examined and graded at the 7th and 21st days after fractures. Nicotine or saline treatment continued throughout the experiment. Median fracture healing score was found to be 0 (min. 0 - max. 1) in nicotine-treated rats, and 1 (min. 0 - max. 2) in controls, at the 7th day. At the 21st day, the median scores were 2 (min. 1 - max. 3), and 3 (min. 2 - max. 3) in experimental and control groups, respectively. Scores were significantly decreased in nicotine-treated rats both at the 7th and 21st days (p = 0.0465 and p = 0.0175, respectively). We suppose that nicotine impaired fracture healing in the rat forearm model possibly by diminishing nutritional blood flow via vasoconstriction and by its direct effect on osteogenesis.

A laboratory test was undertaken to evaluate the interfacial frictional characteristics of cortical and cancellous bone, as well as a novel porous tantalum biomaterial (Hedrocel^®, Implex Corp.). Three sets of tests were conducted to measure the friction coefficients of (1) bovine cancellous bone against bovine cortical bone; (2) net-shape formed porous tantalum against bovine cortical and cancellous bone; and (3) electron-discharge-machine formed (EDM'd) porous tantalum against bovine cortical and cancellous bone. The bovine cortical bone was tested in three conditions: periosteum-intact, periosteum-denuded and surface-flattened. An inclined plane apparatus was used to determine the coefficients of friction. By gradually increasing the substrate tilt, the angle of slippage was determined, and the friction coefficient was calculated.

The average friction coefficients of cancellous bone against periosteum-intact, periosteum-denuded and surface-flattened cortical bone were 0.91±0.14, 0.61± 0.07 and 0.58±0.06, respectively. Porous tantalum specimens prepared from a preshaped vitreous carbon skeleton, when tested against periosteum-intact, periosteum-denuded and surface-flattened cortical bone, and against cancellous bone, had average friction coefficients of 1.10±0.18, 0.82±0.15, 0.86±0.11, and 0.98±0.17, respectively. Porous tantalum specimens prepared by electron-discharge machining, when tested against periosteum-intact cortical bone, periosteum-denuded cortical bone and cancellous bone, had average friction coefficients of 1.75±0.33, 0.74±0.07, and 0.88±0.09, respectively. The friction coefficient of the porous tantalum material was very high in comparison to natural bone autografts or allografts, and to conventional orthopedic implant coating materials (sintered beads and wire mesh). Other factors being equal, this high-friction characteristic would be expected to translate into higher initial stability of a porous tantalum implant, as compared to natural bone grafts.