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1.
PLoS One ; 16(10): e0257368, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34613997

RESUMEN

Cremation 168 from the second half of the 8th century BCE (Pithekoussai's necropolis, Ischia Island, Italy), better known as the Tomb of Nestor's Cup, is widely considered as one of the most intriguing discoveries in the Mediterranean Pre-Classic archaeology. A drinking cup, from which the Tomb's name derives, bears one of the earliest surviving examples of written Greek, representing the oldest Homeric poetry ever recovered. According to previous osteological analyses, the Cup is associated with the cremated remains of a juvenile, aged approximately 10-14 years at death. Since then, a vast body of literature has attempted to explain the unique association between the exceptionality of the grave good complex, the symposiac and erotic evocation of the Nestor's Cup inscription with the young age of the individual buried with it. This paper reconsiders previous assessments of the remains by combining gross morphology with qualitative histology and histomorphometric analyses of the burnt bone fragments. This work reveals the commingled nature of the bone assemblage, identifying for the first time, more than one human individual mixed with faunal remains. These outcomes dramatically change previous reconstructions of the cremation deposit, rewriting the answer to the question: who was buried with Nestor's Cup?.


Asunto(s)
Cremación/historia , Adolescente , Arqueología/historia , Restos Mortales/anatomía & histología , Restos Mortales/ultraestructura , Huesos/anatomía & histología , Huesos/ultraestructura , Niño , Historia Antigua , Humanos , Italia
3.
Cell Tissue Bank ; 21(2): 249-256, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32067198

RESUMEN

Radiation sterilization is an effective method of bone sterilization prior to bone graft transplantation. Gamma irradiation affects the biological and mechanical properties of bone; depending on the dose of radiation. The effect of gamma irradiation on bone mechanical properties is an unwanted phenomenon. However the mechanism of the effect of irradiation on bone mechanical properties is not properly understood. In this research paper the mechanism of the effect of gamma irradiation on bovine bone is investigated using scanning electron microscopy, energy-dispersive X-rays spectroscopy and Fourier transform infrared spectroscopy techniques. Gamma irradiation affects the mineral and fiber composition of bovine bone. The mineral content of bone especially calcium, magnesium and phosphorus decrease with increasing dose of gamma radiation. At Nano-level gamma irradiation alter amide I, amide II and amide III collagen contents. High dose gamma irradiation induces collagen cross-linking reaction in bone and degrades bone properties.


Asunto(s)
Huesos/efectos de la radiación , Rayos gamma , Animales , Huesos/ultraestructura , Calcio/análisis , Bovinos , Colágeno/química , Cadera/fisiología , Fósforo/análisis , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
4.
Med Hypotheses ; 134: 109427, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31622920

RESUMEN

There have been increasing numbers of reports that anti-osteoporosis drugs cause osteonecrosis. A typical example is medication-related osteonecrosis of the jaws (MRONJ) which can cause massive necrosis and defects of the jaws. Thus, the dosage and effects of anti-osteoporosis drugs should be re-examined. Our hypothesis is that primary moderate osteoporosis itself is beneficial for bones and should not be excessively treated other than vitamin D, calcium supplementation and functional exercises. The self-repair and anti-infection abilities of bone depend on its organic tissues including stem cells, blood vessels, osteoclastic and osteogenic factors in bone, which jointly fight against invading pathogens and repair bone damage. Recent evidence supports age-related changes in mesenchymal stem cell including loss of self-renewal and increases in senescent cell numbers. Thus, the number of MSCs and vessels need to be increased to achieve functions similar to those in young people. This requires dissolving a portion of inorganic materials and providing extra space to hold more cells and blood vessels. In contrast, anti-osteoporosis drugs prevent bone destruction, and increase mineralization that occupies the space of organic materials, reduces bone immunity and self-repair. Moreover, long term use of anti-osteoporosis drugs also have negative effects on long bones and cartilages. Therefore, moderate age-related osteoporosis is natural in humans to protect bones. Excessive treatment of osteoporosis weakens immunity and self-repair.


Asunto(s)
Conservadores de la Densidad Ósea/efectos adversos , Huesos/metabolismo , Modelos Biológicos , Osteoporosis/fisiopatología , Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Conservadores de la Densidad Ósea/uso terapéutico , Huesos/irrigación sanguínea , Huesos/citología , Huesos/ultraestructura , Calcio/uso terapéutico , Autorrenovación de las Células , Senescencia Celular , Terapia Combinada , Implantes Dentales , Terapia por Ejercicio , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Osteoporosis/tratamiento farmacológico , Osteoporosis/terapia , Vitamina D/uso terapéutico
5.
Calcif Tissue Int ; 104(2): 160-170, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30293198

RESUMEN

Vitamin D supplementation is often used in the prevention and treatment of osteoporosis, but the role of vitamin D has lately been questioned. We aimed to investigate the effect of 3 months of daily vitamin D3 supplementation (70 µg [2800 IU] vs. placebo) initiated in winter months on bone health. This study is a double-blinded placebo-controlled randomized trial. Bone health was assessed by bone turnover markers, DXA, HRpQCT, and QCT scans. The participants were 81 healthy postmenopausal women with low 25(OH)D (< 50 nmol/l) and high PTH levels (> 6.9 pmol/l) at screening. Vitamin D3 supplementation significantly increased levels of 25(OH)D and 1,25(OH)2D by 59 nmol/l and 19 pmol/l, respectively, whereas PTH was reduced by 0.7 pmol/l (all p < 0.0001). Compared with placebo, vitamin D3 did not affect bone turnover markers, aBMD by DXA or trabecular bone score. Vitamin D3 increased trabecular vBMD (QCT scans) in the trochanter region (0.4 vs. - 0.7 g/cm3) and the femoral neck (2.1 vs. - 1.8 g/cm3) pall < 0.05. HRpQCT scans of the distal tibia showed reduced trabecular number (- 0.03 vs. 0.05 mm-1) and increased trabecular thickness (0.001 vs. - 0.005 mm), as well as an improved estimated bone strength as assessed by failure load (0.1 vs. - 0.1 kN), and stiffness (2.3 vs. - 3.1 kN/mm pall ≤ 0.01). Changes in 25(OH)D correlated significantly with changes in trabecular thickness, stiffness, and failure load. Three months of vitamin D3 supplementation improved bone strength and trabecular thickness in tibia, vBMD in the trochanter and femoral neck, but did not affect aBMD.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/ultraestructura , Colecalciferol/uso terapéutico , Hiperparatiroidismo Secundario/tratamiento farmacológico , Deficiencia de Vitamina D/tratamiento farmacológico , Anciano , Huesos/química , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/complicaciones , Persona de Mediana Edad , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/prevención & control , Placebos , Estaciones del Año , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/complicaciones
6.
Cell Physiol Biochem ; 51(1): 356-374, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30453296

RESUMEN

BACKGROUND/AIMS: Osteoporosis is a bone metabolic disease that affects mostly post-menopausal women. There has been shown that vitamin K (VK) supplementation during menopause may decrease bone loss as well as risk of bone breaking. Aiming to clarify the beneficial role of VK in bone metabolism during menopause, we investigated mineral metabolism and bone ultrastructure of ovariectomized (OVX) mice. METHODS: To determine the effects chronic use of VK in bone structure and mineral metabolism in OVX mice, we used several methods, such as DXA, µCTScan, and SEM as well as biomolecular techniques, such as ELISA and qRT-PCR. In addition, complete analysis of serum hormonal and other molecules associated to bone and lipid metabolism were evaluated overview the effects of VK in menopause murine model. RESULTS: VK treatment significantly affects Pi metabolism independently of OVX, changing Pi plasma, urinary output, balance, and Pi bone mass. Interestingly, VK also increased VLDL in mice independently of castration. In addition, VK increased compact bone mass in OVX mice when we evaluated it by DXA, histomorphometry, µCTScanning. VK increased bone formation markers, osteocalcin, HYP- osteocalcin, and AP whereas it decreased bone resorption markers, such as urinary DPD/creatinine ratio and plasmatic TRAP. Surprisingly, SEM images revealed that VK treatment led to amelioration of microfractures observed in OVX untreated controls. In addition, SHAM operated VK treated mice exhibited higher number of migrating osteoblasts and in situ secretion of AP. OVX led to decreased to in situ secretion of AP that was restored by VK treatment. Moreover, VK treatment increased mRNA expression of bone Calbindin 28KDa independently of OVX. CONCLUSION: VK treatment in OVX mice exhibited beneficial effects on bone ultrastructure, mostly by altering osteoblastic function and secretion of organic bone matrix. Therefore, VK could be useful to treat osteopenic/osteoporotic patients.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/metabolismo , Vitamina K/farmacología , Fosfatasa Alcalina/sangre , Animales , Huesos/diagnóstico por imagen , Huesos/ultraestructura , Calbindinas/genética , Calbindinas/metabolismo , Creatinina/orina , Suplementos Dietéticos , Modelos Animales de Enfermedad , Femenino , Metabolismo de los Lípidos , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Rastreo , Osteocalcina/sangre , Osteoporosis/metabolismo , Osteoporosis/patología , Ovariectomía , Hormona Paratiroidea/sangre , Columna Vertebral/diagnóstico por imagen , Microtomografía por Rayos X
7.
Phytother Res ; 32(12): 2487-2500, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30306652

RESUMEN

Although radix Salviae miltiorrhizae (RSM) is reported to exhibit the antiosteoporotic effect in preclinical study, the underlying mechanism is unclear. To this end, ovariectomized (OVX) rats were employed with administration of RSM (5 g/kg) for 14 weeks. The disturbed serum levels of alkaline phosphatase (ALP), osteoprotegerin (OPG), tartrate-resistant acid phosphatase, and receptor activator of nuclear factor-κB ligand (RANKL) in OVX rats were improved by RSM treatment. Furthermore, supplement of RSM to OVX rats resulted in an increase in femoral bone mineral density and bone strength as well as an improvement in bone microstructures. Moreover, the decreased expression of phosphor (p)-LRP6, insulin-like growth factor-1(IGF-1), ALP, and OPG, as well as increased expression of RANKL and cathepsin K in the tibias and femurs of OVX rats were shifted by RSM treatment. Additionally, RSM reversed the decreased ratio of p-glycogen synthase kinase 3ß (GSK3ß) to GSK3ß and increased ratio of p-ß-catenin to ß-catenin in OVX rats. Altogether, it is suggestive that RSM improves bone quantity and quality by favoring Wnt/ß-catenin and OPG/RANKL/cathepsin K signaling pathways in OVX rats thereby suggesting the potential of this herb to be a novel source of antiosteoporosis drugs.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Salvia miltiorrhiza/química , Animales , Huesos/ultraestructura , Catepsina K/metabolismo , Femenino , Fémur/efectos de los fármacos , Fémur/ultraestructura , Resistencia Flexional/efectos de los fármacos , FN-kappa B/metabolismo , Ovariectomía , Ligando RANK/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo
8.
Microsc Res Tech ; 81(8): 887-896, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29785759

RESUMEN

The aim was to investigate the effect of the Er-YAG laser radiation on morphology and chemical composition of enamel, dentin, and bone. The specimens of the three groups were irradiated with a very long pulse mode (VLP) of 2.94 µm Er-YAG laser with 100 mJ pulse energy and energy density of 8.42 J/ c m 2 for 30 s, at a repetition rate of 15 Hz. The organic and inorganic content of the samples were investigated by Fourier Transforms Infrared spectroscopy (FTIR). The morphological characteristics were investigated with scanning electron microscopy (SEM) and elemental analysis (calcium and phosphorus) with energy-dispersive X-ray spectroscopy (EDX). FTIR data were analyzed with a One-Way ANCOVA test and EDX data with the independent sample t-test. Following the laser radiation, FTIR showed a significant decrease in the organic content of all tissues. The weight percentage (wt %) calcium content of dentin and bone increased significantly following irradiation with a p-value of .002 for both tissues, but the wt % of phosphorus content was not influenced significantly. The morphological alterations expressed signs of fusion in all the samples.


Asunto(s)
Huesos/efectos de la radiación , Esmalte Dental/efectos de la radiación , Dentina/efectos de la radiación , Compuestos Inorgánicos/análisis , Láseres de Estado Sólido , Terapia por Luz de Baja Intensidad , Compuestos Orgánicos/análisis , Diente Premolar/química , Diente Premolar/efectos de la radiación , Diente Premolar/ultraestructura , Huesos/química , Huesos/ultraestructura , Esmalte Dental/química , Esmalte Dental/ultraestructura , Dentina/química , Dentina/ultraestructura , Humanos , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
9.
PLoS One ; 13(4): e0196342, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29684086

RESUMEN

Transverse lines, called Harris Lines (HL), osteological markers of recovery from growth arrest episodes, are visible in radiograms of recent and Pleistocene fossil bones. Since on the one hand they mark stressful episodes in life, and on the other are mainly used to trace health fluctuations in prehistoric human communities, I used a cave bear population to check if the processes that could affect the specie' condition were in any way reflected in the bone structure. 392 bear bones from Bear Cave in Kletno (collection: Department of Palaeozoology, University of Wroclaw), dated as 32 100 ±1300 to >49 000 years BP, were radiologically examined. The bones were found in a non-anatomical position; morphological analysis indicated that they belonged to different individuals. HL shadows were observed on 9 tibiae and 3 radii: 8.8% out of the 59 tibiae and 77 radii and 3.1% of all the bones. At least 3 transverse lines were recognised in those cases; the specimens were histologically examined. The bear individuals in question experienced regular malnutrition periods during their ontogeny. Starvation resulting in growth inhibition involved young individuals, aged 1 to 4 years. Juveniles aged 6 months, i.e. before weaning, or younger, showed no signs of nutritional stress. Starvation periods associated with seasonal food deficit were not long or common and had no significant effect on the development and welfare of the species. This is the first description of the occurrence of transverse lines in the Pleistocene bear.


Asunto(s)
Desarrollo Óseo/fisiología , Huesos/anatomía & histología , Ambiente , Fósiles/anatomía & histología , Ursidae/anatomía & histología , Ursidae/crecimiento & desarrollo , Animales , Huesos/patología , Huesos/ultraestructura , Fósiles/patología , Fósiles/ultraestructura , Historia Antigua , Paleontología , Polonia , Tibia/anatomía & histología , Tibia/crecimiento & desarrollo , Tibia/patología
10.
Technol Health Care ; 25(S1): 13-20, 2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28582887

RESUMEN

OBJECTIVE: Bone histomorphometry and the concentration of the serum osteocalcin expression were observed in disuse osteoporosis (DOP) rats in order to explore the mechanism of pulsed electromagnetic fields in treating DOP. METHODS: Female SD rats, weighing 250 ∼ 280 g, were randomly divided into 4 groups: a control group and three experimental groups. The right hindlimbs of all the rats were immobilized by tibia-tail fixation, except for those in the INT group. The ALN group rats were given an alendronate sodium (1 mg kg-1 d-1) treatment, and the rats in the PEMF group received PEMF irradiation. Bone histomorphometry and the concentration of serum osteocalcin expression were detected in 2, 4, 8, and 12 weeks. RESULTS: Four weeks after modeling, as compared with the DOP group, the %Tb-Ar and Tb-N in the ALN group were increased, and the difference was significant (P< 0.05 or P< 0.01). At 8 weeks, as compared with the DOP group, the %Tb-Ar and Tb-N in the ALN group and the PEMF group both increased, and there was a significant difference (P< 0.05 or P< 0.01). At 12 weeks, as compared with the DOP group, the BGP serum concentration of the ALN group was reduced, and there was a statistical difference (P< 0.05). CONCLUSION: Pulse electromagnetic field with drug can prevent disuse osteoporosis by changing the bone microstructure. In the long run, PEMF improves the mechanical performance of biological structures better than alendronate sodium does. PEMF may influence the process of bone remodeling by promoting the level of osteocalcin.


Asunto(s)
Magnetoterapia , Osteocalcina/sangre , Osteoporosis/terapia , Animales , Huesos/patología , Huesos/ultraestructura , Femenino , Magnetoterapia/métodos , Microscopía Electrónica , Osteoporosis/etiología , Osteoporosis/patología , Ratas , Ratas Sprague-Dawley
11.
Int J Mol Med ; 39(5): 1155-1163, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28339032

RESUMEN

Epidemiological investigations indicate that certain ingredients in tea bricks can antagonize the adverse effects of fluoride. Tea polyphenols (TPs), the most bioactive ingredient in tea bricks, have been demonstrated to be potent bone-supporting agents. ClC­7 is known to be crucial for osteoclast (OC) bone resorption. Thus, in this study, we investigated the potential protective effects of TPs against fluorosis using a mouse model and explored the underlying mechanisms with particular focus on ClC­7. A total of 40, healthy, 3­week­old male C57BL/6 mice were randomly divided into 4 groups (n=10/group) by weight as follows: distilled water (control group), 100 mg/l fluoridated water (F group), water containing 10 g/l TPs (TP group) and water containing 100 mg/l fluoride and 10 g/l TPs (F + TP group). After 15 weeks, and after the mice were sacrificed, the long bones were removed and bone marrow-derived macrophages were cultured ex vivo in order to perform several experiments. OCs were identified and counted by tartrate­resistant acid phosphatase (TRAP) staining. The consumption of fluoride resulted in severe fluorosis and in an impaired OC function [impaired bone resorption, and a low mRNA expression of nuclear factor of activated T-cells 1 (NFATc1), ATPase H+ transporting V0 subunit D2 (ATP6v0d2) and osteopetrosis­associated transmembrane protein 1 (Ostm1)]. In the F + TP group, fluorosis was attenuated and OC function was restored, but not the high bone fluoride content. Compared with the F group, mature OCs in the F + TP group expressed higher mRNA levels of ClC­7 and Ostm1; the transportation and retaining of Cl­ was improved, as shown by the fluorescence intensity experiment. On the whole, our findings indicate that TPs mitigate fluorosis in C57BL/6 mice by regulating OC bone resorption. Fluoride inhibits OC resorption by inhibiting ClC­7 and Ostm1, whereas TPs attenuate this inhibitory effect of fluoride.


Asunto(s)
Huesos/efectos de los fármacos , Huesos/metabolismo , Fluorosis Dental/genética , Proteínas de la Membrana/genética , Polifenoles/farmacología , Té/química , Animales , Biomarcadores , Peso Corporal/efectos de los fármacos , Resorción Ósea/genética , Resorción Ósea/metabolismo , Huesos/patología , Huesos/ultraestructura , Modelos Animales de Enfermedad , Fluorosis Dental/metabolismo , Fluorosis Dental/patología , Fluorosis Dental/prevención & control , Expresión Génica , Homeostasis , Inmunohistoquímica , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteoclastos/ultraestructura , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología
12.
PLoS One ; 11(4): e0154120, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27115490

RESUMEN

Nutrition during pregnancy and lactation could exert a key role not only on maternal bone, but also could influence the skeletal development of the offspring. This study was performed in rats to assess the relationship between maternal dietary intake of prebiotic oligofructose-enriched inulin and its role in bone turnover during gestation and lactation, as well as its effect on offspring peak bone mass/architecture during early adulthood. Rat dams were fed either with standard rodent diet (CC group), calcium-fortified diet (Ca group), or prebiotic oligofructose-enriched inulin supplemented diet (Pre group), during the second half of gestation and lactation. Bone mineral density (BMD) and content (BMC), as well as micro-structure of dams and offspring at different stages were analysed. Dams in the Pre group had significantly higher trabecular thickness (Tb.Th), trabecular bone volume fraction (BV/TV) and smaller specific bone surface (BS/BV) of the tibia in comparison with CC dams. The Pre group offspring during early adulthood had an increase of the lumbar vertebra BMD when compared with offspring of CC and Ca groups. The Pre group offspring also showed significant increase versus CC in cancellous and cortical structural parameters of the lumbar vertebra 4 such as Tb.Th, cortical BMD and decreased BS/BV. The results indicate that oligofructose-enriched inulin supplementation can be considered as a plausible nutritional option for protecting against maternal bone loss during gestation and lactation preventing bone fragility and for optimizing peak bone mass and architecture of the offspring in order to increase bone strength.


Asunto(s)
Huesos/efectos de los fármacos , Inulina/farmacología , Oligosacáridos/administración & dosificación , Prebióticos/administración & dosificación , Ratas/fisiología , Animales , Densidad Ósea/efectos de los fármacos , Desarrollo Óseo/efectos de los fármacos , Huesos/anatomía & histología , Huesos/ultraestructura , Femenino , Inulina/administración & dosificación , Lactancia/efectos de los fármacos , Prebióticos/análisis , Embarazo , Ratas/anatomía & histología , Ratas/crecimiento & desarrollo , Ratas Sprague-Dawley
13.
Connect Tissue Res ; 56(2): 133-43, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25825970

RESUMEN

UNLABELLED: PURPOSE/AIMS OF THE STUDY: Bone's hierarchical structure can be visualized using a variety of methods. Many techniques, such as light and electron microscopy generate two-dimensional (2D) images, while micro-computed tomography (µCT) allows a direct representation of the three-dimensional (3D) structure. In addition, different methods provide complementary structural information, such as the arrangement of organic or inorganic compounds. The overall aim of the present study is to answer bone research questions by linking information of different 2D and 3D imaging techniques. A great challenge in combining different methods arises from the fact that they usually reflect different characteristics of the real structure. MATERIALS AND METHODS: We investigated bone during healing by means of µCT and a couple of 2D methods. Backscattered electron images were used to qualitatively evaluate the tissue's calcium content and served as a position map for other experimental data. Nanoindentation and X-ray scattering experiments were performed to visualize mechanical and structural properties. RESULTS: We present an approach for the registration of 2D data in a 3D µCT reference frame, where scanning electron microscopies serve as a methodic link. Backscattered electron images are perfectly suited for registration into µCT reference frames, since both show structures based on the same physical principles. We introduce specific registration tools that have been developed to perform the registration process in a semi-automatic way. CONCLUSIONS: By applying this routine, we were able to exactly locate structural information (e.g. mineral particle properties) in the 3D bone volume. In bone healing studies this will help to better understand basic formation, remodeling and mineralization processes.


Asunto(s)
Huesos/patología , Curación de Fractura , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Microtomografía por Rayos X , Animales , Huesos/ultraestructura , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Microscopía Electrónica de Rastreo/métodos , Ratas , Tomografía Computarizada por Rayos X/métodos
14.
J Forensic Sci ; 60(3): 770-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25677640

RESUMEN

Dissolving bodies is a current method of disposing of human remains and has been practiced throughout the years. During the last decade in the Netherlands, two cases have emerged in which human remains were treated with acid. In the first case, the remains of a cremated body were treated with hydrofluoric acid. In the second case, two complete bodies were dissolved in a mixture of hydrochloric and sulfuric acid. In both cases, a great variety of evidence was collected at the scene of crime, part of which was embedded in resin, polished, and investigated using SEM/EDX. Apart from macroscopic findings like residual bone and artificial teeth, in both cases, distinct microscopic residues of bone were found as follows: (partly) digested bone, thin-walled structures, and recrystallized calcium phosphate. Although some may believe it is possible to dissolve a body in acid completely, at least some of these microscopic residues will always be found.


Asunto(s)
Huesos/ultraestructura , Cadáver , Ácido Fluorhídrico/química , Microscopía Electrónica de Rastreo , Ácido Nítrico/química , Ácidos Sulfúricos/química , Huesos/química , Fosfatos de Calcio/química , Cloruros/química , Cromatografía por Intercambio Iónico , Cremación , Fluoruros/química , Patologia Forense , Humanos , Masculino , Nitratos/química , Fósforo/química , Espectrometría por Rayos X
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 3545-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26737058

RESUMEN

Since the 1980s several methods of electrostimulative techniques have been developed to accelerate bone regeneration during orthopedic treatment. These techniques have proven to provide increased bone formation while curing fractures and bone diseases. The electric parameters, however, are mostly results of empiric research regarding the bone tissue as homogeneous material. Especially cancellous bone, which is the objective of a new electrostimulative total hip revision system, has a porous, inhomogeneous microstructure. The present work investigates numerically the electric field distribution within this tissue using microscopic computer tomography scans of small bone samples. The 3-dimensional X-ray absorption values of these scans are correlated with conductivity values from literature applying different correlation approaches. Compared to electric fields within a homogeneous material strong elevations can be observed within the structures which include most of the bone forming cells.


Asunto(s)
Huesos/fisiología , Terapia por Estimulación Eléctrica/métodos , Prótesis e Implantes , Animales , Regeneración Ósea , Huesos/ultraestructura , Diseño Asistido por Computadora , Fémur/fisiología , Fémur/ultraestructura , Fracturas Óseas/terapia , Porosidad , Porcinos , Tomografía Computarizada por Rayos X
16.
Curr Osteoporos Rep ; 12(3): 351-6, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24969723

RESUMEN

Strength is the most widely reported parameter with regards to bone failure. However, bone contains pre-existing damage and stress concentration sites, perhaps making measures of fracture toughness more indicative of the resistance of the tissue to withstand fracture. Several toughening mechanisms have been identified in bone, prominently, at the microscale. More recently, nanoscale toughness mechanisms, such as sacrificial-bonds and hidden-length or dilatational band formation, mediated by noncollagenous proteins, have been reported. Absence of specific noncollagenous proteins results in lowered fracture toughness in animal models. Further, roles of several other, putative influencing, factors such as closely bound water, collagen cross-linking and citrate bonds in bone mineral have also been proposed. Yet, it is still not clear if and which mechanisms are hallmarks of osteoporosis disease and how they influence fracture risk. Further insights on the workings of such influencing factors are of high importance for developing complementary diagnostics and therapeutics strategies.


Asunto(s)
Huesos/metabolismo , Fracturas Óseas/metabolismo , Osteoporosis/metabolismo , Fenómenos Biomecánicos , Huesos/ultraestructura , Humanos
17.
Int J Clin Exp Pathol ; 7(2): 640-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24551284

RESUMEN

This study aims to investigate the effects of low-dose subchronic exposure to lead acetate (Pb(NO3)2) and cadmium chloride (CdCl2·2.5H2O) on bone in rats. The rats were assigned randomly to a control group and three experimental groups that were given the mixture of Pb(NO3)2 and CdCl2·2.5H2O by gastric gavage at doses of 0 mg/kg body weight (b.w.) (Group I, to serve as a control), 29.96 mg/kg b.w. (Group II, 29.25+0.71), 89.88 mg/kg b.w. (Group III, 87.74+2.14), and 269.65 mg/kg b.w. (Group IV, 263.23+6.42) for at least 90 consecutive days. Calcium (Ca) and phosphorus (Pi) contents in the bone were determined. Bone mineral density (BMD) was measured at the tibia and femur region by dual-energy X-ray absorbsiometry. The histopathology of bone was evaluated by light microscope, scanning electron microscope, and transmission electron microscope. The BMD of rats in the experimental group was significantly lower and the contents of Ca and Pi were decreased than those in the control group. The histopathological evaluation showed that co-induction of Pb and Cd results in bone microstructure damage, especially to trabecular bone, marrow cavity, collagen fiber, and osteoblast. In general, results indicate that combining Pb with Cd induces bone damage and increases the risk of osteoporosis.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Cloruro de Cadmio/toxicidad , Calcio/metabolismo , Compuestos Organometálicos/toxicidad , Osteoporosis/inducido químicamente , Fósforo/metabolismo , Absorciometría de Fotón , Animales , Huesos/diagnóstico por imagen , Huesos/metabolismo , Huesos/ultraestructura , Microscopía Electroquímica de Rastreo , Microscopía Electrónica de Transmisión , Osteoporosis/diagnóstico , Osteoporosis/metabolismo , Ratas , Ratas Sprague-Dawley , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Pruebas de Toxicidad Subcrónica
18.
J Ethnopharmacol ; 151(1): 352-60, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24212078

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Velvet antlers (VA) have been claimed for centuries to have numerous medical benefits including strengthen bones. To investigate and compare the anti-osteoporotic activities from different sections of VA. MATERIALS AND METHODS: Fresh VA prepared from farmed sika deers (Cervus nippon) was divided into upper (VAU), middle (VAM), and basal (VAB) sections. The chemical constituents and anti-osteoporotic effect of different sections from VA were evaluated using ovariectomized rats. RESULTS: Levels of water-soluble extracts, diluted alcoholic extract, amino acids, testosterone, insulin-like growth factor (IGF)-1 and testosterone plus estradiol significantly differed among the different sections. Levels of these constituents were significantly higher in the upper section than in the basal section. Moreover, levels of testosterone and IGF-1 of the VAM were also significantly higher than those of the VAB. Calcium level increased downward from the tip with statistical significance. The strength of vertebrae increased in all VA-treated groups compared to the control, but only treatment with VAU and VAM increased the strength of the femur and the microarchitecure of the trabecular bone. Alkaline phosphatase levels of VAU- and VAM-treated groups significantly decreased, but osteocalcin did not significantly change. Moreover, VAU and VAM dose-dependently increased proliferation and mineralization of MC3T3-E1 cells. CONCLUSION: Our study provides strong evidence for the regional differences in the effectiveness of velvet antler in treating osteoporosis. However, further studies are needed to elucidate the bioactive chemical constituents associated with the anti-osteoporotic effects of velvet antler.


Asunto(s)
Cuernos de Venado , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Osteoporosis/prevención & control , Células 3T3 , Animales , Cuernos de Venado/química , Fenómenos Biomecánicos , Huesos/ultraestructura , Calcio/metabolismo , Ciervos , Esquema de Medicación , Estradiol/química , Femenino , Factor I del Crecimiento Similar a la Insulina/química , Medicina Tradicional China , Ratones , Ovariectomía , Distribución Aleatoria , Ratas , Testosterona/química
19.
Bone ; 57(2): 455-67, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24063947

RESUMEN

This study investigates bony protrusions within a narrowed periodontal ligament space (PDL-space) of a human bone-PDL-tooth fibrous joint by mapping structural, biochemical, and mechanical heterogeneity. Higher resolution structural characterization was achieved via complementary atomic force microscopy (AFM), nano-transmission X-ray microscopy (nano-TXM), and microtomography (MicroXCT™). Structural heterogeneity was correlated to biochemical and elemental composition, illustrated via histochemistry and microprobe X-ray fluorescence analysis (µ-XRF), and mechanical heterogeneity evaluated by AFM-based nanoindentation. Results demonstrated that the narrowed PDL-space was due to invasion of bundle bone (BB) into PDL-space. Protruded BB had a wider range with higher elastic modulus values (2-8GPa) compared to lamellar bone (0.8-6GPa), and increased quantities of Ca, P and Zn as revealed by µ-XRF. Interestingly, the hygroscopic 10-30µm interface between protruded BB and lamellar bone exhibited higher X-ray attenuation similar to cement lines and lamellae within bone. Localization of the small leucine rich proteoglycan biglycan (BGN) responsible for mineralization was observed at the PDL-bone interface and around the osteocyte lacunae. Based on these results, it can be argued that the LB-BB interface was the original site of PDL attachment, and that the genesis of protruded BB identified as protrusions occurred as a result of shift in strain. We emphasize the importance of bony protrusions within the context of organ function and that additional study is warranted.


Asunto(s)
Huesos/fisiología , Articulaciones/fisiología , Ligamento Periodontal/fisiología , Diente/fisiología , Biglicano/metabolismo , Fenómenos Biomecánicos , Huesos/diagnóstico por imagen , Huesos/ultraestructura , Calcio/metabolismo , Cemento Dental/diagnóstico por imagen , Cemento Dental/fisiología , Módulo de Elasticidad , Proteínas de la Matriz Extracelular/metabolismo , Fibromodulina , Fluorescencia , Humanos , Inmunohistoquímica , Articulaciones/ultraestructura , Microscopía de Fuerza Atómica , Modelos Biológicos , Ligamento Periodontal/citología , Ligamento Periodontal/diagnóstico por imagen , Ligamento Periodontal/ultraestructura , Fósforo/metabolismo , Proteoglicanos/metabolismo , Propiedades de Superficie , Diente/diagnóstico por imagen , Diente/ultraestructura , Microtomografía por Rayos X , Zinc/metabolismo
20.
J Biomed Mater Res A ; 101(6): 1539-49, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23065866

RESUMEN

The aim of this study was to investigate the in vivo biocompatibility in terms of healing of long segmental bone defect in rabbit model as well as in vitro cytotoxicity of eluates of compression-molded High density polyethylene (HDPE)-hydroxyapatite (HA)-aluminum oxide (Al2O3) composite-based implant material. Based on the physical property in terms of modulus and strength properties, as reported in our recent publication, HDPE-40 wt % HA and HDPE-20 wt % HA-20 wt % Al2O3 hybrid composites were used for biocompatibility assessment. Osteoblasts cells were cultured in conditioned media, which contains varying amount of composite eluate (0.01, 0.1, and 1.0 wt %). In vitro, the eluates did not exhibit any significant negative impact on proliferation, mineralization or on morphology of human osteoblast cells. In vivo, the histological assessment revealed neobone formation at the bone/implant interface, characterized by the presence of osteoid and osteoblasts. The observation of osteoclastic activity indicates the process of bone remodeling. No inflammation to any noticeable extent was observed at the implantation site. Overall, the combination of in vitro and in vivo results are suggestive of potential biomedical application of compression-molded HDPE- 20 wt % HA- 20 wt % Al2O3 composites to heal long segmental bone defects without causing any toxicity of bone cells.


Asunto(s)
Óxido de Aluminio/farmacología , Materiales Biocompatibles/farmacología , Fuerza Compresiva , Durapatita/farmacología , Oseointegración/efectos de los fármacos , Osteoblastos/citología , Polietileno/farmacología , Animales , Antraquinonas/metabolismo , Huesos/efectos de los fármacos , Huesos/ultraestructura , Calcificación Fisiológica/efectos de los fármacos , Recuento de Células , Muerte Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Humanos , Implantes Experimentales , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Oxazinas/metabolismo , Conejos , Difracción de Rayos X , Xantenos/metabolismo
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