Journal articles: 'Spectra; Bone'

1

Freeman, John J., and Matthew J. Silva. "Separation of the Raman Spectral Signatures of Bioapatite and Collagen in Compact Mouse Bone Bleached with Hydrogen Peroxide." Applied Spectroscopy 56, no. 6 (June 2002): 770–75. http://dx.doi.org/10.1366/000370202760077513.

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We studied the effectiveness of hydrogen peroxide in removing visible laser-induced photoluminescence from the Raman spectra of compact bone of mice. In testing various bone sample preparations, we found that hydrogen peroxide bleaching was most effective when applied directly to fresh or fresh-frozen bone samples. The extent of the reduction in photoluminescence in the peroxide-bleached bone was such that the Raman spectrum could be readily recorded with 532-nm laser excitation. A comparison of bone samples before and after hydrogen peroxide bleaching shows that the Raman shifts of all the collagen and bioapatite bands are unaffected by the peroxide bleach. Moreover, the low spectral backgrounds of the peroxide-treated bone samples permit the Raman spectra of these two major components of bone to be fully separated. The Raman spectrum of collagen-rich periosteum was subtracted from the Raman spectrum of compact bone, which isolated the Raman spectral signature of the bioapatite fraction of the bone. This derived spectrum of bioapatite was then used, through spectral subtraction, to generate the spectral signature of the collagen component of the bone. All the major and minor Raman bands of collagen and bioapatite can be identified in these separate spectra.

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Krmar, M., S. Shukla, and K. Ganezer. "Bone densitometry using x-ray spectra." Physics in Medicine and Biology 55, no. 20 (September 24, 2010): 6105–23. http://dx.doi.org/10.1088/0031-9155/55/20/005.

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Иванов-Омский, В. И., К. С. Рутковский, Н. И. Гуляев, А. С. Галенко, and С. Г. Ястребов. "Идентификация Н-связей кальцинированного аортального клапана." Письма в журнал технической физики 45, no. 18 (2019): 24. http://dx.doi.org/10.21883/pjtf.2019.18.48233.17792.

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AbstractThe IR absorption spectra of subendothelial regions of the aortic valve cusps of a patient with calcified aortic stenosis diagnosis were measured by the attenuated total reflectance (ATR) spectroscopy technique in a frequency interval of 2500–3600 cm^–1 and analyzed in comparison to the spectra of healthy human tissues and reference spectra of a pig’s healthy bone and aortic valve. The IR absorption band structure in this spectral region was studied by means of expansion into Gaussian components. The energies of hydrogen bonds (H-bonds) involving O–H groups were estimated. It is established that, among all samples studied, the energy of H-bonds between hydroxyl groups reaches maximum in the bone tissue.

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Notingher, Ioan, G. Jell, P. L. Notingher, I. Bisson, Julia M. Polak, and Larry L. Hench. "Raman Spectroscopy: Potential Tool for In-Situ Characterization of Bone Cell Differentiation." Key Engineering Materials 284-286 (April 2005): 545–48. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.545.

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The Classical Least Square (CLS) fitting method was used to analyze the Raman spectra of living cells with the aim of identification of new phenotype-specific spectral markers for osteoblasts. The following chemicals were used for the CLS model: DNA, RNA, serum albumin, chymotrypsin and phosphatidyl choline. In this study we analyzed primary mature osteoblasts as well as two other cell types used as potential sources of osteoblasts: embryonic stem cells and fetal bone cells. The results obtained suggest that the Raman spectra of the cell types can be well approximated with a linear combination of the Raman spectra of the biopolymers used in the CLS model. The relative concentrations of the CLS components varied significantly between cell types, indicating that this analytical method could be used for phenotypic identification of osteoblasts.

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Lomeí Mejia, P. A., G. Urriolagoitía, J. L. Jiménez Pérez, Luis Héctor Hernández-Gómez, H. Lecona Butron, and A. Cruz Orea. "Photoacoustic Spectroscopy Applied to the Study of Bone Consolidation in Fractures." Materials Science Forum 480-481 (March 2005): 339–44. http://dx.doi.org/10.4028/www.scientific.net/msf.480-481.339.

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By using photoacoustic (PA) spectroscopy it was performed a study about bone consolidation in fractures. It was obtained the optical absorption spectra of callus of male rat fractured bones at different consolidation times. From these spectra it was possible to observe the presence of alkaline phosphatase through their absorption peaks which were compared with characteristic peaks reported in the literature for this phosphatase. In this study we showed that alkaline phosphatase could be considered as an indicator of the repair process of bone fractures.

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Feng, Ting, Yunhao Zhu, Kenneth M. Kozloff, Basma Khoury, Yejing Xie, Xueding Wang, Meng Cao, Jie Yuan, Dean Ta, and Qian Cheng. "Bone Chemical Composition Assessment with Multi-Wavelength Photoacoustic Analysis." Applied Sciences 10, no. 22 (November 19, 2020): 8214. http://dx.doi.org/10.3390/app10228214.

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In this study, the feasibility of assessing the chemical composition in bone using the multi-wavelength photoacoustic analysis (MWPA) method was investigated. By illuminating a bone specimen using laser light with a wavelength tunable over an optical spectrum from 680 nm to 950 nm, the optical absorption spectrum of the bone was acquired. Then, with the optical absorption spectra of all the optically absorbing chemical components in the bone known, a spectral unmixing procedure was performed to quantitatively assess the relative content of each chemical component. The experimental results from porcine rib bones demonstrated that the contents of the chemical components, including not only non-organic materials such as minerals and water but also organic materials including oxygenated hemoglobin, deoxygenated hemoglobin, lipid, and collagen, can all be assessed by MWPA. As the chemical composition in the bone is directly associated with functional and metabolic activities, the finding from this study suggests that the MWPA method could offer a new diagnostic tool for the non-invasive evaluation of bone health.

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Eichler, J., E. Diessel, S. de Magalhaes, O. Goncalves, W. Gowin, and D. Felsenberg. "Continuous X-ray spectra in bone densitometry." Osteoporosis International 6, S1 (January 1996): 170. http://dx.doi.org/10.1007/bf02500219.

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8

Brown, C. E., J. H. Battocletti, R. Srinivasan, J. R. Allaway, J. Moore, and P. Sigmann. "In vivo 31P nuclear magnetic resonance spectroscopy of bone mineral for evaluation of osteoporosis." Clinical Chemistry 34, no. 7 (July 1, 1988): 1431–38. http://dx.doi.org/10.1093/clinchem/34.7.1431.

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Abstract The mineral content of stationary bone samples can be quantified by 31P nuclear magnetic resonance (NMR) spectroscopy. The assay can be performed in regions of the anatomy that pose problems for absorptiometric techniques, because the mineral content is measured within a selected volume without concern for the geometry of the bone. In vivo 31P NMR spectra of the bones in human fingers and wrist are reported. Soft tissue such as marrow and skeletal muscle contributes little to the 31P NMR spectra of human fingers and wrist and thus should not seriously affect the accuracy of the mineral assay. 31P NMR spectrometry should prove helpful for confirming rapid bone mineral loss in those at risk and for monitoring response to treatment.

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9

Oxmann, J. F. "Technical Note: An X-ray absorption method for the identification of calcium phosphate species using peak-height ratios." Biogeosciences 11, no. 8 (April 17, 2014): 2169–83. http://dx.doi.org/10.5194/bg-11-2169-2014.

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Abstract. X-ray absorption near edge structure (XANES) studies on calcium phosphate species (Ca-P) deal with marginal differences among subtle spectral features despite a hitherto missing systematic breakdown of these differences. Related fingerprinting approaches depend, therefore, on spectral libraries that are not validated against each other, incomplete and scattered among publications. This study compiled a comprehensive spectral library from published reference compound libraries in order to establish more clear-cut criteria for Ca-P determination by distinctive phosphorus K-edge XANES features. A specifically developed normalization method identified diagnostic spectral features in the compiled library, e.g. by uniform calculation of ratios between white-line and secondary peak heights. Post-processing of the spectra (n = 81) verified distinguishability among most but not all phases, which included hydroxylapatite (HAP), poorly crystalline HAP, amorphous HAP, fluorapatite, carbonate fluorapatite (CFAP), carbonate hydroxylapatite, β-tricalcium phosphate, octacalcium phosphate (OCP), brushite, monetite, monocalcium phosphate, amorphous calcium phosphate (ACP), anapaite, herderite, scholzite, messelite, whiteite and P on CaCO3. Particularly, peak-height ratios significantly improved analyte specificity, e.g. by supplementary breakdown into OCP and ACP. The spectral analysis also revealed Ca-P standards that were rarely investigated or inappropriately synthesized, and thus provides a basis for standard selection and synthesis. The method developed and resulting breakdown by species were subsequently tested on Ca-P spectra from studies on bone and sediment. The test indicated that bone material likely comprises only poorly crystalline apatite, which confirms direct nucleation of apatite in bone. This biological apatite formation is likely opposed to that of sedimentary apatite, which apparently forms by both direct nucleation and successive crystallization. Application of the method to μXANES spectra of sediment particles indicated authigenic apatite formation by an OCP precursor.

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Oxmann, J. F. "An X-ray absorption method for the identification of calcium phosphate species using peak height ratios." Biogeosciences Discussions 10, no. 11 (November 28, 2013): 18723–56. http://dx.doi.org/10.5194/bgd-10-18723-2013.

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Abstract. X-ray absorption near edge structure (XANES) studies on calcium phosphate species (Ca-P) deal with marginal differences among subtle spectral features despite a hitherto missing systematic breakdown of these differences. Related fingerprinting approaches depend therefore on spectral libraries that are not validated against each other, incomplete and scattered among publications. This study compiled a comprehensive spectral library from published reference compound libraries in order to establish more clear-cut criteria for Ca-P determination by distinctive phosphorus K-edge XANES features. A specifically developed normalization method identified diagnostic spectral features within the compiled library, e.g. by uniform calculation of ratios between white-line and secondary peak heights. Post-processing of the spectra (n = 81) verified distinguishability among most but not all phases, which included hydroxylapatite (HAP), poorly crystalline HAP, amorphous HAP, fluorapatite, carbonate fluorapatite (CFAP), carbonate hydroxylapatite, β-tricalcium phosphate, octacalcium phosphate (OCP), brushite, monetite, monocalcium phosphate, amorphous calcium phosphate (ACP), anapaite, herderite, scholzite, messelite, whiteite and P on CaCO3. Particularly, peak height ratios significantly improved analyte specificity, e.g. by supplementary breakdown into OCP and ACP. The spectral analysis also revealed Ca-P standards that were rarely investigated or inappropriately synthesized, and thus provides a basis for standard selection and synthesis. The developed method and resulting breakdown by species were subsequently tested on Ca-P spectra from studies on bone and sediment. The test indicated that bone material likely comprises only poorly crystalline apatite, which implies direct nucleation of apatite in bone. This biological apatite formation is likely opposed to that of sedimentary apatite, which apparently forms by successive crystallization. Application of the method to μXANES spectra of sediment particles indicated authigenic apatite formation by an OCP precursor.

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Esmonde-White, Karen A., Francis W. L. Esmonde-White, Michael D. Morris, and Blake J. Roessler. "Effects of pathology dyes on Raman bone spectra." Journal of Biomedical Optics 18, no. 5 (May 2, 2013): 057002. http://dx.doi.org/10.1117/1.jbo.18.5.057002.

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Gao, Fei, Simiao Zhou, Zengling Yang, Lujia Han, and Xian Liu. "Study on the Characteristic Spectral Properties for Species Identification of Animal-Derived Feedstuff Using Fourier Transform Infrared Spectroscopy." Applied Spectroscopy 71, no. 11 (October 2, 2017): 2446–56. http://dx.doi.org/10.1177/0003702817732323.

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The objective of the present study was to explore the effective spectral bands related to lipid characteristics in spectra of raw animal-derived feedstuff and figure out which marked spectral regions (single or combined) contributed more to species discrimination. A total of 82 meat and bone meals, including porcine, poultry, bovine, ovine, and fish, were studied. Raw materials, extracted lipid, and defatted samples were simultaneously analyzed and calculated using Fourier transform infrared (FT-IR) spectroscopy in combination with chemometric methods. Taking the spectra of lipid as references, five marked spectral regions considered the main lipid characteristic regions were found in the raw animal-derived feedstuff spectra. In the study, single and combined marked spectral bands were investigated and proved to have better performance than the whole spectra of raw terrestrial animal-derived feedstuff and fishmeal. For the discrimination of five animal species, the regions of 1800–1650 cm–1, 1500–1330 cm–1, 1260–1060 cm–1, and 790–640 cm–1 presented better results; for the classification of three categories, the regions of 3100–2800 cm–1, 1800–1650 cm–1, and 1500–1330 cm–1 showed the best results.

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13

Chaber, Radosław, Christopher Arthur, Kornelia Łach, Anna Raciborska, Elżbieta Michalak, Katarzyna Bilska, Katarzyna Drabko, Joanna Depciuch, Ewa Kaznowska, and Józef Cebulski. "Predicting Ewing Sarcoma Treatment Outcome Using Infrared Spectroscopy and Machine Learning." Molecules 24, no. 6 (March 19, 2019): 1075. http://dx.doi.org/10.3390/molecules24061075.

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Background: Improved outcome prediction is vital for the delivery of risk-adjusted, appropriate and effective care to paediatric patients with Ewing sarcoma—the second most common paediatric malignant bone tumour. Fourier transform infrared (FTIR) spectroscopy of tissues allows the bulk biochemical content of a biological sample to be probed and makes possible the study and diagnosis of disease. Methods: In this retrospective study, FTIR spectra of sections of biopsy-obtained bone tissue were recorded. Twenty-seven patients (between 5 and 20 years of age) with newly diagnosed Ewing sarcoma of bone were included in this study. The prognostic value of FTIR spectra obtained from Ewing sarcoma (ES) tumours before and after neoadjuvant chemotherapy were analysed in combination with various data-reduction and machine learning approaches. Results: Random forest and linear discriminant analysis supervised learning models were able to correctly predict patient mortality in 92% of cases using leave-one-out cross-validation. The best performing model for predicting patient relapse was a linear Support Vector Machine trained on the observed spectral changes as a result of chemotherapy treatment, which achieved 92% accuracy. Conclusion: FTIR spectra of tumour biopsy samples may predict treatment outcome in paediatric Ewing sarcoma patients with greater than 92% accuracy.

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Buchwald, Tomasz, Marek Kozielski, and Mirosław Szybowicz. "Determination of Collagen Fibers Arrangement in Bone Tissue by Using Transformations of Raman Spectra Maps." Spectroscopy: An International Journal 27 (2012): 107–17. http://dx.doi.org/10.1155/2012/261487.

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The goal of this work was to evaluate the ability of Raman spectroscopy to identify molecular organization and chemical composition of extracellular matrix such as the collagen fibers arrangement, the level of mineralization, and the carbonate accumulation in mineral phase in spongy bone of the human head of the femur. Changes in composition and structure of the spongy bone tissue were illustrated using maps of polarized Raman spectra. In particular, the purpose of the present study was determination of arrangement of mineralized collagen on surface of trabecula by using transformations of Raman spectra maps. Transformations of Raman spectra maps were needed in order to remove impact of chemical composition on images of Raman spectra map, which display the collagen fibers orientation. These transformations allow to obtain simultaneously the distribution of constituents of bone and arrangement of collagen fibers on tissue surface. A method to indicate the collagen orientations is developed to understand the molecular organization in healthy and unhealthy bone at the microstructural level.

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15

Henzan, Tomoko, Toshihiro Miyamoto, Ken-ichi Izumi, Akihiko Numata, Kenjiro Kamezaki, Satoshi Yamasaki, Kumi Kiyoshima, et al. "BONE MARROW PROCESSING IN ABO-INCOMPATIBLE BONE MARROW TRANSPLANTATION USING COBE SPECTRA CELL SEPARATOR." Japanese Journal of Transfusion and Cell Therapy 52, no. 6 (2006): 693–97. http://dx.doi.org/10.3925/jjtc.52.693.

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Kourkoumelis, Nikolaos, and Margaret Tzaphlidou. "Multivariate statistical evaluation of bone site and sex as parameters for the Fourier transform infrared spectroscopic study of normal bone." Spectroscopy 24, no. 1-2 (2010): 99–104. http://dx.doi.org/10.1155/2010/317263.

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Fourier transform infrared spectroscopy combined with multivariate analysis was performed on a series of bone samples in order to investigate possible differences in the molecular fingerprint based on classification either between different sex and bone sites. Cortical femoral, tibia and ulna samples from five male and five female normal Wistar rats were analysed. PCA analysis classified successfully sex-related spectra since the first three principal components explained 95% of the total variance. This was not the case for bone site-related spectra. In all cases, an important aspect is the ionic exchange of phosphate and carbonate ions.

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Matousek, P., I. P. Clark, E. R. C. Draper, M. D. Morris, A. E. Goodship, N. Everall, M. Towrie, W. F. Finney, and A. W. Parker. "Subsurface Probing in Diffusely Scattering Media Using Spatially Offset Raman Spectroscopy." Applied Spectroscopy 59, no. 4 (April 2005): 393–400. http://dx.doi.org/10.1366/0003702053641450.

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We describe a simple methodology for the effective retrieval of Raman spectra of subsurface layers in diffusely scattering media. The technique is based on the collection of Raman scattered light from surface regions that are laterally offset away from the excitation laser spot on the sample. The Raman spectra obtained in this way exhibit a variation in relative spectral intensities of the surface and subsurface layers of the sample being investigated. The data set is processed using a multivariate data analysis to yield pure Raman spectra of the individual sample layers, providing a method for the effective elimination of surface Raman scatter. The methodology is applicable to the retrieval of pure Raman spectra from depths well in excess of those accessible with conventional confocal microscopy. In this first feasibility study we have differentiated between surface and subsurface Raman signals within a diffusely scattering sample composed of two layers: trans-stilbene powder beneath a 1 mm thick over-layer of PMMA (poly(methyl methacrylate)) powder. The improvement in contrast of the subsurface trans-stilbene layer without numerical processing was 19 times. The potential applications include biomedical subsurface probing of specific tissues through different overlying tissues such as assessment of bone quality through skin, providing an effective noninvasive means of screening for bone degeneration, other skeletal disease diagnosis, and dermatology studies, as well as materials and catalyst research.

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Makowski, Alexander J., Mathilde Granke, Oscar D. Ayala, Sasidhar Uppuganti, Anita Mahadevan-Jansen, and Jeffry S. Nyman. "Applying Full Spectrum Analysis to a Raman Spectroscopic Assessment of Fracture Toughness of Human Cortical Bone." Applied Spectroscopy 71, no. 10 (July 14, 2017): 2385–94. http://dx.doi.org/10.1177/0003702817718149.

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A decline in the inherent quality of bone tissue is a † Equal contributors contributor to the age-related increase in fracture risk. Although this is well-known, the important biochemical factors of bone quality have yet to be identified using Raman spectroscopy (RS), a nondestructive, inelastic light-scattering technique. To identify potential RS predictors of fracture risk, we applied principal component analysis (PCA) to 558 Raman spectra (370–1720 cm–1) of human cortical bone acquired from 62 female and male donors (nine spectra each) spanning adulthood (age range = 21–101 years). Spectra were analyzed prior to R-curve, nonlinear fracture mechanics that delineate crack initiation (Kinit) from crack growth toughness (Kgrow). The traditional ν1phosphate peak per amide I peak (mineral-to-matrix ratio) weakly correlated with Kinit (r = 0.341, p = 0.0067) and overall crack growth toughness (J-int: r = 0.331, p = 0.0086). Sub-peak ratios of the amide I band that are related to the secondary structure of type 1 collagen did not correlate with the fracture toughness properties. In the full spectrum analysis, one principal component (PC5) correlated with all of the mechanical properties (Kinit: r = − 0.467, Kgrow: r = − 0.375, and J-int: r = − 0.428; p < 0.0067). More importantly, when known predictors of fracture toughness, namely age and/or volumetric bone mineral density (vBMD), were included in general linear models as covariates, several PCs helped explain 45.0% (PC5) to 48.5% (PC7), 31.4% (PC6), and 25.8% (PC7) of the variance in Kinit, Kgrow, and J-int, respectively. Deriving spectral features from full spectrum analysis may improve the ability of RS, a clinically viable technology, to assess fracture risk.

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Querido, William, Ramyasri Ailavajhala, Mugdha Padalkar, and Nancy Pleshko. "Validated Approaches for Quantification of Bone Mineral Crystallinity Using Transmission Fourier Transform Infrared (FT-IR), Attenuated Total Reflection (ATR) FT-IR, and Raman Spectroscopy." Applied Spectroscopy 72, no. 11 (July 20, 2018): 1581–93. http://dx.doi.org/10.1177/0003702818789165.

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Bone mineral crystallinity is an important factor determining bone quality and strength. The gold standard method to quantify crystallinity is X-ray diffraction (XRD), but vibrational spectroscopic methods present powerful alternatives to evaluate a greater variety of sample types. We describe original approaches by which transmission Fourier transform infrared (FT-IR), attenuated total reflection (ATR) FT-IR, and Raman spectroscopy can be confidently used to quantify bone mineral crystallinity. We analyzed a range of biological and synthetic apatite nanocrystals (10–25 nm) and found strong correlations between different spectral factors and the XRD determination of crystallinity. We highlight striking differences between FT-IR spectra obtained by transmission and ATR. In particular, we show for the first time the absence of the 1030 cm−1 crystalline apatite peak in ATR FT-IR spectra, which excludes its use for analyzing crystallinity using the traditional 1030/1020 cm−1 ratio. The ν4PO4 splitting ratio was also not adequate to evaluate crystallinity using ATR FT-IR. However, we established original approaches by which ATR FT-IR can be used to determine apatite crystallinity, such as the 1095/1115 and 960/1115 cm−1 peak ratios in the second derivative spectra. Moreover, we found a simple unified approach that can be applied for all three vibrational spectroscopy modalities: evaluation of the ν1PO4 peak position. Our results allow the recommendation of the most reliable analytical methods to estimate bone mineral crystallinity by vibrational spectroscopy, which can be readily implemented in many biomineralization, archeological and orthopedic studies. In particular, we present a step forward in advancing the use of the increasingly utilized ATR FT-IR modality for mineral research.

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Schulmerich, Matthew V., Kathryn A. Dooley, Thomas M. Vanasse, Steven A. Goldstein, and Michael D. Morris. "Subsurface and Transcutaneous Raman Spectroscopy and Mapping Using Concentric Illumination Rings and Collection with a Circular Fiber-Optic Array." Applied Spectroscopy 61, no. 7 (July 2007): 671–78. http://dx.doi.org/10.1366/000370207781393307.

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Different spatial separations between an illumination ring and a bundle of 50 collection fibers focused to collect light in the center of the ring were used to investigate the recovery of subsurface Raman spectra. The depth of Raman signal recovery and the preservation of spatial information in the recovered signal were investigated using polymer blocks stacked in different geometries. The illumination rings were then combined into a single data set to increase variation in the signal. Multivariate data analysis was used to recover the Raman spectra of the subsurface component. The Raman spectrum of a Delrin target was recoverable at depths up to 22.6 mm of overlying Teflon. Spatial information was lost at approximately 6.5 mm below the Teflon surface. The same protocols were used to recover canine bone spectra transcutaneously at depths up to 5 mm below the skin's surface. The recovered bone spectra were validated by exposed bone measurements.

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Rothmann, Chana, Amos M. Cohen, and Zvi Malik. "Chromatin Condensation in Erythropoiesis Resolved by Multipixel Spectral Imaging: Differentiation Versus Apoptosis." Journal of Histochemistry & Cytochemistry 45, no. 8 (August 1997): 1097–108. http://dx.doi.org/10.1177/002215549704500807.

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Chromatin condensation and nuclear organization of May–Grunwald–Giemsa (MGG)-stained normal erythropoietic bone marrow cells and apoptotic red cell precursors were resolved by spectral bio-imaging. Multipixel spectra were obtained from single cells displaying a range of wavelengths of both transmitted and absorbed light. Two groups of spectra, of low- and high-intensity transmitted light, were revealed in the nuclei of each cell. The absorbance spectra served for the reconstruction of “absorbance images” depicting the affinity of MGG stain for the chromatin of proerythroblasts and of basophilic, polychromatic, and orthochromatic normoblasts. The localization of different spectral components in the nuclei was resolved employing two mathematical methods, spectral similarity mapping and principal component analysis. Novel structures of high symmetry revealing windmill-like organization were detected in basophilic, polychromatic, and orthochromatic normoblast cells. Matching structures were detected in apoptotic normoblasts obtained from an agnogenic myeloid metaplasia patient. Apoptosis was associated with a gradual breakdown of the ordered arrays in the nucleus. We propose that DNA cleavage may lead to fragmentation of the symmetrical windmill-like superstructure of the basic nuclear domains. (J Histochem Cytochem 45:1097–1108, 1997)

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Bertotto, Mercedes, Marcelo Bello, Susana Binotti, Matías Agnese, Sandra Bachur, and Damián Dedó. "Detection of animal by-products in bone ashes by near infrared spectroscopy coupled with microscopy." Journal of Near Infrared Spectroscopy 26, no. 1 (February 2018): 26–33. http://dx.doi.org/10.1177/0967033518756176.

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Bovine spongiform encephalopathy is a mortal bovine disease. Epidemiologic studies have linked the disease to animal feed contaminated with infected protein. In Argentina, the feeding of bovines with components of animal origin is banned, except for fishmeal and bone ash. Nowadays, optical microscopy is used to analyze animal feed and its components. In this method, technical analytical expertise is very important. This is why the development of a methodology that produces results which can be rapidly and automatically compared is urgently needed. The specific infrared microscopy method presented in this work delivers qualitative results in terms of the presence or absence of animal particles by applying specific decision rules. The object of this work was to assess the methodology of near infrared microscopy for the qualitative determination of the presence of particles of animal origin in matrices of bone ash. The spectra were collected by an image microscope coupled to a Fourier transform infrared spectrometer operating in the reflection mode. Four mappings were done per sample, obtaining 1000 spectra per mapping. They were selected from an area on the slide of 50 particles in the axis X and 20 particles in the axis Y. Spectra were automatically collected at these points. In order to find the fragments of animal origin in the samples, a specific software program was developed. The program analyzed the spectra and evaluated the presence of bone fragments. From the validation results, it could be inferred that 4000 spectra should be observed in order to achieve a detection limit of 0.05 g bone fragments 100 g−1 bone ash. Selectivity, intermediate precision and repeatability were also analyzed with satisfactory results. Therefore, the validated method can be easily applied in routine analysis of bone ashes.

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Sowa, Michael G., and Henry H. Mantsch. "FT-IR Step-Scan Photoacoustic Phase Analysis and Depth Profiling of Calcified Tissue." Applied Spectroscopy 48, no. 3 (March 1994): 316–19. http://dx.doi.org/10.1366/0003702944028182.

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Rapid-scan- and step-scan-based Fourier transform infrared photoacoustic depth profiling results of an extracted but intact human tooth are compared. The effects of various data processing methods are examined. Analysis of the phase dispersion of the photothermal signal along with spectral linearization is used to access the extent of photoacoustic saturation in the photoacoustic spectra. Phase-modulated/phase-resolved depth profiling methods are less prone to photoacoustic saturation and provide superior localization of the surface and subsurface absorbers distributed in the tooth enamel. Mid-infrared depth profiling studies of calcified tissues can aid in the understanding of degenerative bone diseases, bone growth, and modeling, as well as tissue mineralization.

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ZHENG, Changyan, Tieyong CAO, Jibin YANG, Xiongwei ZHANG, and Meng SUN. "Spectra Restoration of Bone-Conducted Speech via Attention-Based Contextual Information and Spectro-Temporal Structure Constraint." IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E102.A, no. 12 (December 1, 2019): 2001–7. http://dx.doi.org/10.1587/transfun.e102.a.2001.

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Veljković, Dobrila, Olivera Šerbić Nonković, Zorica Radonjić, Miloš Kuzmanović, and Željko Zečević. "Bone marrow processing for transplantation using Cobe Spectra cell separator." Transfusion and Apheresis Science 48, no. 3 (June 2013): 359–63. http://dx.doi.org/10.1016/j.transci.2013.04.017.

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Pantelkin, V., V. Zhuravleva, and A. Tsoviyanov. "Development of Chemical Samples Preparation Method to Reduce the Lower Limit of Absorbed Dose Assessment by Electron Paramagnetic Resonance Spectrometry." Medical Radiology and radiation safety 65, no. 2 (April 29, 2020): 50–56. http://dx.doi.org/10.12737/1024-6177-2020-65-2-50-56.

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Purpose: Development of a method of chemical sample preparation to reduce the lower limit of the absorbed dose estimation by EPR spectrometry. Material and methods: The required number of bone samples was prepared to study the effect of chemical treatment of bone material samples in organic solvents on their EPR spectra. They were subjected to primary treatment to separate the bones from the remains of soft biological tissue, then a dense bone was isolated and its defatting was carried out. Further, a series of parallel experiments on chemical treatment of bone materials in solutions of three organic reducing agents (hydrazine hydrate, ethylenediamine and diethylenetriamine) were done to reduce the magnitude of the native signal when carrying out works on reconstruction of absorbed doses using EPR spectroscopy. Recording of EPR spectra was performed on the ELEXSYS E500 Bruker spectrometer equipped with a high-q cylindrical resonator SHQE. Irradiation of the samples was carried out on the X-ray biological unit RUB RUST-M1. Results: To reduce the lower limit of detection of the absorbed dose and improve the reliability of the assessment of the absorbed dose using the EPR method, it is required to reduce the native component of the EPR signal without affecting, if possible, the radiation component of the EPR signal. To achieve this effect, a chemical treatment in solutions of amines was proposed, which affect the collagen compounds that present in the bones and which are responsible for the appearance of a native signal in the EPR spectrum. After chemical treatment of bone material samples at 30°C for 30 minutes in a solution of different amines, there was a significant decrease in the amplitude of the native signal, which was: 4 for hydrazine hydrate, 3.3 for diethylenetriamine and 2.1 for ethylenediamine. For bone material samples that were subjected to the proposed chemical treatment in hydrazine hydrate, it is possible to confidently determine the amplitude of the radiation signal by a value of 2–3 Gy against the minimum dose values of 6–8 Gy for bone material samples that were not chemically treated. Conclusion: It was found that during the chemical treatment there is a significant reduction of the native signal in the spectra of EPR of bone materials, the decrease of the radiation signal at the same time was slightly. Comparison of the results of treatment of bone materials in three organic reducing agents showed that the best results are obtained by the use of hydrazine hydrate at a temperature of 30°C for 30 minutes.

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Miranda, Humberto, Renato Aparecido De Souza, Maira Gaspar Tosato, Roberto Simão, Murilo Xavier Oliveira, Flávia Mafra De Lima, Erika Ferrari, Wellington Ribeiro, Leonardo Marmo Moreira, and Airton Abrahão Martin. "Effect of different doses of creatine on the bone in thirty days of supplementation in mice: FT-Raman study." Spectroscopy 25, no. 5 (2011): 225–33. http://dx.doi.org/10.1155/2011/212038.

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In this study, Raman spectroscopy was employed in order to provide information about the effects of different doses of creatine on bone tissue composition of phosphate apatite (960 cm–1), carbonate apatite (1170 cm–1) representing the mineral content and collagen matrix (amide I, 1665 cm–1). The animals (27 Balb-C male) were divided into three groups (n═ per group): control (CON), supplemented with 0.5 g/kg (Cre-0.5) and with 2.0 g/kg (Cre-2.0) creatine. The experiment was carried out for thirty days. After this time, the right femur of each animal was harvested. The specimens were assessment by FT-Raman spectroscopy and in a total of 81 spectra were acquired in the medial diaphysis of the femur. The Raman data strongly suggest that only the creatine supplementation of 0.5 g/kg effective to the bone constitution. Furthermore, the present results demonstrate that creatine ingestion provokes decrease in the relative presence of carbonate in the chemical constitution of bones. The decrease in the carbonate content can be associated to a significantly bone resistance altered to several mammalians. The analysis evidenced that the mineral concentrations in the Raman spectroscopy could be a feasible method for non-invasive or minimally invasive assessment of bone tissue composition. Probably this high sensitivity can be employed to determine spectral profiles, such as wavelength of maximum absorption and maximum intensity of absorption of each wavelength, of several bone diseases.

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Vos, Maarten, Károly Tökési, and Ilona Benkö. "The Potential of Materials Analysis by Electron Rutherford Backscattering as Illustrated by a Case Study of Mouse Bones and Related Compounds." Microscopy and Microanalysis 19, no. 3 (May 3, 2013): 576–86. http://dx.doi.org/10.1017/s143192761300041x.

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AbstractElectron Rutherford backscattering (ERBS) is a new technique that could be developed into a tool for materials analysis. Here we try to establish a methodology for the use of ERBS for materials analysis of more complex samples using bone minerals as a test case. For this purpose, we also studied several reference samples containing Ca: calcium carbonate (CaCO3) and hydroxyapatite and mouse bone powder. A very good understanding of the spectra of CaCO3 and hydroxyapatite was obtained. Quantitative interpretation of the bone spectrum is more challenging. A good fit of these spectra is only obtained with the same peak widths as used for the hydroxyapatite sample, if one allows for the presence of impurity atoms with a mass close to that of Na and Mg. Our conclusion is that a meaningful interpretation of spectra of more complex samples in terms of composition is indeed possible, but only if widths of the peaks contributing to the spectra are known. Knowledge of the peak widths can either be developed by the study of reference samples (as was done here) or potentially be derived from theory.

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Drzazga, Zofia, Wojciech Ciszek, and Mariusz Binek. "Prenatal Zidovudine Treatment Modifies Early Development of Rat Osteoid – Confocal Microspectroscopy Analysis." Journal of Fluorescence 29, no. 5 (September 2019): 1257–63. http://dx.doi.org/10.1007/s10895-019-02429-6.

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Abstract Autofluorescence of the bone extracellular matrix (ECM) has not been widely explored although the ECM plays a very important role in bone development. In our research we focused on examining the bone matrix of very young animals due to the intense growth process during the first month of life. Structure images and fluorescence spectra of the bone surface were carried out using confocal fluorescence microscope Eclipse Ti-S inverted CLSM (NIKON, Japan) for compact tibia of healthy 7-, 14- and 28-day-old rat newborns after prenatal zidovudine administration in comparison with control. Spectral features of ECM autofluorescence were analyzed statistically by taking into consideration p < 0.05. The CLSM technique allows for simultaneous examination of the structure and autofluorescence from selected areas of the bone surface. Excessive autofluorescence of ECM after prenatal zidovudine administration influences bone growth incommensurably to the newborns’ age. Therefore the possibility of an additional non-enzymatic mechanism of collagen cross-linking in the first two weeks of life of newborn rats prenatally treated with zidovudine has been considered. Our results suggest that ECM autofluorescence can be an indicator of bone development in the normal and pathological state.

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Huang, Zhao Long, Gui Yang Liu, Ying He, Zhong Zhou Yi, and Jun Ming Guo. "Interaction between Hydroxyapatite and Collagen." Advanced Materials Research 412 (November 2011): 384–87. http://dx.doi.org/10.4028/www.scientific.net/amr.412.384.

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To study the interaction between hydroxyapatite (HAP) and collagen in bone, we researched the phenomenon of collagen biomineralization and self-assembly in viro by uv-vis spectra and circular dichroism (CD) spectra. The materials prepared by self-assembly collagen and collagen-HAP showed layer structures. And the product prepared by collagen-HAP had better and more compact appearance. The decrease of speed of collagen self-assembly was caused by calcium ion or strontium ion added. The trough of CD spectra moved down in calcium-containing solution and moved up when forming precipitation of calcium phosphate from the solution. It indicated that the effect of collagen self-assembly was caused by calcium ions, strontium ions etc. in the solution. The IR spectrum proved that a coordinate bond formed between calcium ion and amide groups on collagen.

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Permatasari, Hestining Ajeng, Rosita Wati, Rista Mutia Anggraini, Almukarramah Almukarramah, and Yusril Yusuf. "Hydroxyapatite Extracted from Fish Bone Wastes by Heat Treatment." Key Engineering Materials 840 (April 2020): 318–23. http://dx.doi.org/10.4028/www.scientific.net/kem.840.318.

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The present work demonstrates a low-cost route to produce hydroxyapatite (HAp) from fish bones (natural source) by a simple heat-treatment process. The produced HAp was characterized by X-ray Diffraction (XRD) and Fourier Transform Infra-Red (FTIR). Energy Dispersive X-ray (EDX) analysis obtained elemental composition that confirmed the presence of Ca and P; then the Ca/P mole ratio was calculated. XRD analysis from Chanos chanos and Calarias batracus bone has produced the diffraction peaks at 31.8°, 32.1°, and 32.9° that corresponded to the HAp phase. The presence of functional groups, PO43‒ and OH‒, has been confirmed by FTIR spectra that arecharacteristics of HAp. EDX analysis has shown that the Ca/P mole ratio was similar to the Ca/P mole ratio of the HAp’s stoichiometry (1.66). But actually, not all fish bones can produce pure HAp after the heat-treatment process, such as Tylosurus crocodilus bone. Based on XRD analysis from the main diffraction peak form is a β-TCP phase

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Sowoidnich, Kay, and Heinz-Detlef Kronfeldt. "Fluorescence Rejection by Shifted Excitation Raman Difference Spectroscopy at Multiple Wavelengths for the Investigation of Biological Samples." ISRN Spectroscopy 2012 (August 8, 2012): 1–11. http://dx.doi.org/10.5402/2012/256326.

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Shifted excitation Raman difference spectroscopy (SERDS) was applied for an effective fluorescence removal in the Raman spectra of meat, fat, connective tissue, and bone from pork and beef. As excitation light sources, microsystem diode lasers emitting at 783 nm, 671 nm, and 488 nm each incorporating two slightly shifted excitation wavelengths with a spectral difference of about 10 cm−1 necessary for SERDS operation were used. The moderate fluorescence interference for 783 nm excitation as well as the increased background level at 671 nm was efficiently rejected using SERDS resulting in a straight horizontal baseline. This allows for identification of all characteristic Raman signals including weak bands which are clearly visible and overlapping signals that are resolved in the SERDS spectra. At 488 nm excitation, the spectra contain an overwhelming fluorescence interference masking nearly all Raman signals of the probed tissue samples. However, the essentially background-free SERDS spectra enable determining the majority of characteristic Raman bands of the samples under investigation. Furthermore, 488 nm excitation reveals prominent carotenoid signals enhanced due to resonance Raman scattering which are present in the beef samples but absent in pork tissue enabling a rapid meat species differentiation.

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Genina, Elina A., Alexey N. Bashkatov, and Valery V. Tuchin. "Optical Clearing of Cranial Bone." Advances in Optical Technologies 2008 (May 19, 2008): 1–8. http://dx.doi.org/10.1155/2008/267867.

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We present experimental results on optical properties of cranial bone controlled by administration of propylene glycol and glycerol. Both transmittance and reflectance spectra of human and porcine cranial bone in vitro were measured. For estimation of absorption and reduced scattering coefficients of the bone, the inverse adding-doubling method was used. The decrease of reflectance of the samples under action of the immersion agents was demonstrated. The experiments have shown that administration of the immersion liquids allows for effective controlling of tissue optical characteristics that makes bone more transparent, thereby increasing the ability of light penetration through the tissue. The presented results can be used in developing of functional imaging techniques, including OCT.

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Koristek, Zdenek, and Jiri Mayer. "Bone Marrow Processing for Transplantation Using the COBE Spectra Cell Separator." Journal of Hematotherapy & Stem Cell Research 8, no. 4 (August 1999): 443–48. http://dx.doi.org/10.1089/152581699320207.

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35

Matysiak, W., J. Atanackovic, H. Katalmohseni, S. H. Byun, M. Inskip, W. V. Prestwich, N. Priest, K. Chin, D. Cowan, and D. R. Chettle. "In-Vivo Neutron Activation Analysis for Aluminium in Bone: System Upgrade and Improve Data Analysis." AECL Nuclear Review 2, no. 2 (December 1, 2013): 27–32. http://dx.doi.org/10.12943/anr.2013.00015.

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An existing NaI(Tl) multidetector array at McMaster University used for in vivo measurement of aluminum by means of neutron activation has been recently upgraded with an in-house built pulse processing system. The new system is capable of collecting spectra in coincidence and anticoincidence modes which allows for better discrimination between the 1.78 MeV 28Al peak and the interfering 38Cl peak. The system is interfaced with Matlab and controlled using a custom graphical user interface, which provides periodic spectral data storage during the acquisition. This feature makes it possible to validate the acquired data and the spectral fitting routines through half-life analysis of the radionuclides. A new set of calibration phantoms spanning a narrower range of aluminum concentrations than employed in the previous study, has also been developed. The combined effect of the new improvements resulted in the minimum detectable level of aluminum in aqueous solutions containing Na, Cl, and Ca in physiological levels, equal to approximately 3 µgAl/gCa.

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Jung, Wulf-Ingo, Otto Lutz, and Markus Pfeffer. "Localized NMR Spectroscopy with a 1.5 T Whole- Body Imager Using CODEX." Zeitschrift für Naturforschung A 46, no. 5 (May 1, 1991): 401–4. http://dx.doi.org/10.1515/zna-1991-0504.

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AbstractWith a whole-body NMR imager working at 1.5 T localized 1H and 31P spectra were obtained using the CODEX sequence. Examples are presented: With ethanol 'H spectra the resolution, stability, and sensitivity are documented. Human in vivo investigations of the yellow bone marrow of (13 mm)3 volume elements show well resolved spectra with a good signal-to-noise ratio. An example for 31P spectroscopy is also given

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37

Chakraborty, Santu, Sandip Bag, Subrata Pal, and Alok K. Mukherjee. "Structural and microstructural characterization of bioapatites and synthetic hydroxyapatite using X-ray powder diffraction and Fourier transform infrared techniques." Journal of Applied Crystallography 39, no. 3 (May 10, 2006): 385–90. http://dx.doi.org/10.1107/s0021889806010351.

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Bioapatite, the main constituent of mineralized tissue in mammalian bones and teeth, is similar in structure and composition to calcium hydroxyapatite (HAP), Ca10(PO4)6(OH)2. The crystallographic analyses of four bioapatites of human-, goat- and rabbit-bone and human-teeth origin, and one synthetic HAP preparedviamicrowave irradiation, have been carried out using X-ray powder diffraction techniques. Fourier transform infrared spectra and Rietveld analyses indicate partial replacement of PO43−ions by CO32−ions in all bioapatites.

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Kaewsichan, Lupong, Jasadee Kaewsrichan, and Thitima Chuchom. "Nanostructured Polycaprolactone-Inorganic Phosphate Hybrid Scaffold for Medical Applications." Advanced Materials Research 93-94 (January 2010): 67–70. http://dx.doi.org/10.4028/www.scientific.net/amr.93-94.67.

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New hybrid macroporous scaffolds of polycaprolactone (PCL)/tricalcium phosphate (TCP) were developed by taking into account mechanical properties of the bone to be replaced. FTIR spectra indicated the coating of TCP onto the polymer, providing hydrophilic surfaces necessary for cells to attach. As determined by DSC, the depression of PCL melting point suggested a uniform distribution of PCL within the TCP matrix. SEM micrographs revealed pores of irregular shapes varying from 100-200 µm in size in the resultant structures. Indeed, the pore morphology was precisely determined by the leached particles. The scaffolds could tolerate the impact of at least 5.6 kNm2, making them suitable for use as artificial bones of skull, clavicle and ribs. Rat bone stroma attached and survived on the scaffolds, indicating biocompatible of the used materials. Therefore, the prepared scaffolds would be applicable for bone tissue engineering in the near future.

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39

Farquharson, M. J., R. D. Luggar, and R. D. Speller. "Multivariate calibration for quantitative analysis of EDXRD spectra from a bone phantom." Applied Radiation and Isotopes 48, no. 8 (August 1997): 1075–82. http://dx.doi.org/10.1016/s0969-8043(96)00328-4.

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40

Rudko, V. V., I. P. Vorona, N. P. Baran, and S. S. Ishchenko. "Thermally stimulated transformation of the EPR spectra in γ-irradiated bone tissue." Radiation Measurements 44, no. 3 (March 2009): 239–42. http://dx.doi.org/10.1016/j.radmeas.2009.03.016.

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41

Zougrou, I. M., M. Katsikini, F. Pinakidou, E. C. Paloura, L. Papadopoulou, and E. Tsoukala. "Study of fossil bones by synchrotron radiation micro-spectroscopic techniques and scanning electron microscopy." Journal of Synchrotron Radiation 21, no. 1 (November 2, 2013): 149–60. http://dx.doi.org/10.1107/s1600577513025228.

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Earlymost Villafranchian fossil bones of an artiodactyl and a perissodactyl from the Milia excavation site in Grevena, Greece, were studied in order to evaluate diagenetic effects. Optical microscopy revealed the different bone types (fibro-lamellar and Haversian, respectively) of the two fragments and their good preservation state. The spatial distribution of bone apatite and soil-originating elements was studied using micro-X-ray fluorescence (µ-XRF) mapping and scanning electron microscopy. The approximate value of the Ca/P ratio was 2.2, as determined from scanning electron microscopy measurements. Bacterial boring was detected close to the periosteal region and Fe bearing oxides were found to fill bone cavities,e.g.Haversian canals and osteocyte lacunae. In the perissodactyl bone considerable amounts of Mn were detected close to cracks (the Mn/Fe weight ratio takes values up to 3.5). Goethite and pyrite were detected in both samples by means of metallographic microscopy. The local Ca/P ratio determined with µ-XRF varied significantly in metal-poor spots indicating spatial inhomogeneities in the ionic substitutions. XRF line scans that span the bone cross sections revealed that Fe and Mn contaminate the bones from both the periosteum and medullar cavity and aggregate around local maxima. The formation of goethite, irrespective of the local Fe concentration, was verified by the FeK-edge X-ray absorption fine structure (XAFS) spectra. Finally, SrK-edge extended XAFS (EXAFS) revealed that Sr substitutes for Ca in bone apatite without obvious preference to the Ca1or Ca2unit-cell site occupation.

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Coster, AA, and KR Fox. "Effects of pulsed argon laser energy on bone." Journal of the American Podiatric Medical Association 79, no. 4 (April 1, 1989): 182–85. http://dx.doi.org/10.7547/87507315-79-4-182.

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Several investigators have reported that the presence of calcium may totally preclude resection of plaque material from the lumen of an occluded vessel. Because the authors did not support these findings, they tested the hypothesis and studied the effects of pulsed argon ion laser energy on other non-plaque but dense calcified tissue, such as cortical bone, and found that bone can be cut with ease and safety. Fresh bovine specimens were irradiated with a Spectra Physics model 170 argon ion laser, and the irradiated areas were examined, measured, and photographed.

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43

Hüls, C. M., H. Erlenkeuser, M.-J. Nadeau, P. M. Grootes, and N. Andersen. "Experimental Study on the Origin of Cremated Bone Apatite Carbon." Radiocarbon 52, no. 2 (2010): 587–99. http://dx.doi.org/10.1017/s0033822200045628.

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Bones that have undergone burning at high temperatures (i.e. cremation) no longer contain organic carbon. Lanting et al. (2001) proposed that some of the original structural carbonate, formed during bioapatite formation, survives. This view is based on paired radiocarbon dating of cremated bone apatite and contemporary charcoal. However, stable carbon isotope composition of carbonate in cremated bones is consistently light compared to the untreated material and is closer to the δ13C values seen in C3 plant material. This raises the question of the origin of carbonate carbon in cremated bone apatite. That is, does the isotope signal reflect an exchange of carbon with the local cremation atmosphere and thus with carbon from the burning fuel, or is it caused by isotopic fractionation during cremation?To study the changes in carbon isotopes (14C, 13C) of bone apatite during burning up to 800 °, a modern bovine bone was exposed to a continuous flow of an artificial atmosphere (basically a high-purity O2/N2 gas mix) under defined conditions (temperature, gas composition). To simulate the influence of the fuel carbon available under real cremation conditions, fossil CO2 was added at different concentrations. To yield cremated bone apatite properties similar to archaeological cremated bones, in terms of crystallographic criteria, water vapor had to be added to the atmosphere in the oven. Infrared vibrational spectra reveal large increases in crystal size and loss of carbonate upon cremation. The isotope results indicate an effective carbon exchange between bone apatite carbonate and CO2 in the combustion gases depending on temperature and CO2 concentration. 14C dates on archaeological cremated bone apatite may thus suffer from an old-wood effect. Paired 13C and 14C values indicate that in addition to this exchange, isotope fractionation between CO2 and carbonate, and admixture of carbon from other sources such as possibly collagen or atmospheric CO2, may play a role in determining the final composition of the apatite carbonate.

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Veljkovic, D., O. A. Erbic-Nonkovic, Z. Radonjic, Z. Zecevic, and D. Vujic. "P-20 BONE MARROW PROCESSING FOR TRANSPLANTATION USING THE COBE SPECTRA CELL SEPARATOR." Transfusion and Apheresis Science 47 (September 2012): S31. http://dx.doi.org/10.1016/s1473-0502(12)70056-3.

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45

Law, I. A., R. A. Housley, Norman Hammond, and R. E. M. Hedges. "Cuello: Resolving the Chronology Through Direct Dating of Conserved and Low-Collagen Bone by AMS1." Radiocarbon 33, no. 3 (1991): 303–15. http://dx.doi.org/10.1017/s0033822200040339.

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It is well known that 14C dating of fossil bone with seriously depleted protein levels, or bone that has been consolidated with preservatives, can produce erroneous results. In the tropics, warm and moist soil conditions lead to constant reworking of organic matter and add to the danger of bone contamination. Because of this, 14C dating of preservative-impregnated bone from such areas has rarely been successful. We report here a set of AMS dates on both unconsolidated animal bone and polyvinyl acetate/polyvinyl alcohol (PVA/PV-OH) impregnated human burials from the Maya site of Cuello, Belize. The steps needed to purify the samples are described, together with details on the use of qualitative infra-red (IR) spectra as a means of assessing sample purity.

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46

Bergmann, Florian, Florian Foschum, Leonie Marzel, and Alwin Kienle. "Ex Vivo Determination of Broadband Absorption and Effective Scattering Coefficients of Porcine Tissue." Photonics 8, no. 9 (August 31, 2021): 365. http://dx.doi.org/10.3390/photonics8090365.

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A novel approach for precise determination of the optical scattering and absorption properties of porcine tissue using an optimized integrating sphere setup was applied. Measurements on several sample types (skin, muscle, adipose tissue, bone, cartilage, brain) in the spectral range between 400 nm and 1400 nm were performed. Due to the heterogeneity of biological samples, measurements on different individual animals as well as on different sections for each sample type were carried out. For all samples, we used an index matching method to reduce surface roughness effects and to prevent dehydration. The derived absorption spectra were used to estimate the concentration of important tissue chromophores such as water, oxy- and deoxyhemoglobin, collagen and fat.

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47

Amarie, Sergiu, Paul Zaslansky, Yusuke Kajihara, Erika Griesshaber, Wolfgang W. Schmahl, and Fritz Keilmann. "Nano-FTIR chemical mapping of minerals in biological materials." Beilstein Journal of Nanotechnology 3 (April 5, 2012): 312–23. http://dx.doi.org/10.3762/bjnano.3.35.

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Methods for imaging of nanocomposites based on X-ray, electron, tunneling or force microscopy provide information about the shapes of nanoparticles; however, all of these methods fail on chemical recognition. Neither do they allow local identification of mineral type. We demonstrate that infrared near-field microscopy solves these requirements at 20 nm spatial resolution, highlighting, in its first application to natural nanostructures, the mineral particles in shell and bone. "Nano-FTIR" spectral images result from Fourier-transform infrared (FTIR) spectroscopy combined with scattering scanning near-field optical microscopy (s-SNOM). On polished sections of Mytilus edulis shells we observe a reproducible vibrational (phonon) resonance within all biocalcite microcrystals, and distinctly different spectra on bioaragonite. Surprisingly, we discover sparse, previously unknown, 20 nm thin nanoparticles with distinctly different spectra that are characteristic of crystalline phosphate. Multicomponent phosphate bands are observed on human tooth sections. These spectra vary characteristically near tubuli in dentin, proving a chemical or structural variation of the apatite nanocrystals. The infrared band strength correlates with the mineral density determined by electron microscopy. Since nano-FTIR sensitively responds to structural disorder it is well suited for the study of biomineral formation and aging. Generally, nano-FTIR is suitable for the analysis and identification of composite materials in any discipline, from testing during nanofabrication to even the clinical investigation of osteopathies.

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48

Postic, Srdjan. "Changes in mandible due to osteoporosis." Serbian Dental Journal 54, no. 1 (2007): 16–27. http://dx.doi.org/10.2298/sgs0701016p.

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Introduction: Osteoporosis may occur in bone tissue as a result of ageing. Aim: The aim of this study was to investigate remodeling of old human edentulous mandibular bone due to osteoporosis. Materials and Methods: Osseous surfaces of one edentulous and one dentate mandible were extracted from a cadaver. This study included 5 methods of analysis of bone structures in experimental and control bony samples of human mandibular bones. Absolute densities of samples were determined. SEM analysis and X-ray diffraction analysis of spectra were used to assess bony layers. Results: Minimum density 1.9658 g/cm3 of edentulous ridge site was detected. SEM micrographs indicated reductions of trabecular and lamellar width. Significant differences (p<0.01) in cancellous site width were recorded in experimental basal specimens. Noticeable increase of porosity was observed in 6.35% of edentulous ridge site and 14.06% of experimental basal site. There was a significant correlation between oxygen presence (p=0.046) eroded and defect bone surfaces (p<0.001). Complexes of hydroxyapatite, calcium-phosphate, tetracalcium-pyrophosphate and amorphous calcium-phosphate were inorganic constituents considerable mineral modifications of edentulous ridge site. Conclusion. Based on the results of the present study, various levels of degradation of cortical matrix and cancellous layers of edentulous mandible may be observed as a result of osteoporosis. .

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Hayashi, Tatsuhide, Kentaro Yoshihara, Mayu Kawase, Akimichi Mieki, Hiroyasu Kataoka, Soichiro Hamajima, and Tatsushi Kawai. "rhBMP-2 Induces Immature Muscular Tissue to Differentiate into Bone-Like Tissue In Vitro." Key Engineering Materials 587 (November 2013): 103–8. http://dx.doi.org/10.4028/www.scientific.net/kem.587.103.

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The aim of this study is to induce bone from immature muscular tissue in vitro using recombinant human BMP (rhBMP)-2 and expanded polytetrafluoroethylene (ePTFE) as a scaffold. Commercially available rhBMP-2 was used in this experiment. IMTs were harvested from the forelimbs of 20th Sprague-Dawley embryonic rats and placed into a homogenizer with 10ng/μl of rhBMP-2 and then homogenized. The homogenized IMT was placed on ePTFE and cultured for 2 weeks. The analyses of histological observation, electron probe micro analyzer (EPMA), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were carried out following culture. The bone-like tissue, which was made up of osteoblast-like cells and osteoids, was partially observed by H-E staining. Moreover, strong mineral deposition was observed in the extracellular matrix by von Kossa staining. Ca, P and O were detected in the extracellular matrix by EPMA and were confirmed to be at almost the same position based on the findings of synchronized images. XRD patterns and FTIR spectra of specimen were found to have typical hydroxyapatite crystal peaks and spectra, respectively. These results suggest that rhBMP-2 induced IMT differentiation into bone-like tissue in vitro.

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Gojayev, E., V. Salimova, and Sh Alieva. "SPECTRA OF THERMOSTIMULATED DEPOLARIZATION OF BIOCOMPOSITES WITH FILLERS OF BIOLOGICAL ORIGIN." EurasianUnionScientists 5, no. 1(82) (February 15, 2021): 45–49. http://dx.doi.org/10.31618/esu.2413-9335.2021.5.82.1238.

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The paper presents the results of studying the spectra of thermally stimulated depolarization of high-pressure polyethylene modified with fillers of biocomposites with fillers of biological origin - fish bone and fish scales. It was revealed that the stability and surface density of space charges can be controlled by varying the volumetric content of biological fillers. The optimal values of bio-fillers that contribute to the stability of the surface density of the studied biocomposites have been determined.

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Journal articles on the topic 'Spectra; Bone'

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