Wyniki wyszukiwania - Biblioteka Nauki

1

Attempt to reconstruct body stature basing on circumferences of long bones in fossil body remains

100%

Gralla G. , Mikusek J. , Fudali M.

Folia Morphologica

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1993

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tom 52

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nr 4

2

Rhizomelic chondrodysplasia punctata type 1: report of mutations in 3 children from India

86%

Phadke S. R. , Gupta N. , Girisha K. M. , Kabra M. , Maeda M. , Vidal E. , Moser A. , Steinberg S. , Puri R. D. , Verma I. C. , Braverman N.

Journal of Applied Genetics

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2010

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tom 51

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nr 1

107-110

EN

Rhizomelic chondrodysplasia punctata is a rare autosomal recessive disorder characterized by stippled epiphyses and rhizomelic shortening of the long bones. We report 3 subjects of rhizomelic chondrodysplasia punctata from India and the PEX7 mutations identified in them. The common PEX7-L292X allele, whose high frequency is due to a founder effect in the northern European Caucasian population, was not identified in these patients. Instead, 2 novel alleles are described, including 64_65delGC, which was present on a single PEX7 haplotype and could represent a common allele in the Indian population.

3

Effects of dexamethasone on physical properties and mineral density of long bones in piglets

86%

Sliwa E. , Kowalik S. , Tatara M. R. , Majcher P. , Krupski W. , Studzinski T.

Bulletin of the Veterinary Institute in Puławy

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2005

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tom 49

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nr 1

4

Developmental stability and canalization of limb bones of brown hares Lepus europaeus with varying levels of heterozygosity

86%

Sert H. , Suchentrunk F. , Ludescher B. , Hacklander K.

Acta Theriologica

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2005

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tom 50

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nr 2

EN

We have studied fluctuating asymmetry (FA), as indicator of developmental stability, and between-individual variation, as surrogate of developmental canalization (DC), in long bones (humerus, ulna, radius, femur, tibia) of 72 wild-living adult-sized brown haresLepus europaeus Pallas, 1778 with variable individual heterozygosity (H).H was calculated from 13 polymorphic allozyme loci. According to the “over-dominance hypothesis”, we expected increased developmental stability and canalization at higherH-levels. But at the individual level we did not find any significant correlation between overall FA (FAI) andH. Also, standard deviations (SD) of mean length (over both body sides) of bones did not differ between individuals from two intentionally created groups of hares, namely one with high and one with lowH. FA-indices and variances of FA-indices of bone lengths did not differ significantly when compared between two intentionally created groups of hares with high and low SD of bone lengths, respectively. These latter findings suggest that developmental stability and DC are two separate or partly separate mechanisms of developmental homeostasis in the studied appendicular skeleton, and thatH has no traceable effect on develop-mental homeostasis. If there is still such an effect, it should be clearly smaller than a possibly combined effect of (presently uncontrolled) environmental stressors.

5

Oszacowanie stabilizacji złamania trzonu kości udowej przez płytkę przykostną przy wykorzystaniu metody elementów skończonych

72%

Kozień M. S. , Lorkowski J. , Górka I. , Kornaga M. , Grzegorowska O. , Kotela A. , Kotela I.

Engineering of Biomaterials

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2015

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tom Vol. 18, no. 130

20--26

PL

Złamania kości długich mogą być leczone na kilka sposobów. Jednym z nich jest zastosowanie płytki przykostnej. Płytka zamocowywana do kości umożliwia przeprowadzenie leczenia, ale z drugiej strony jest źródłem powstawania dodatkowych naprężeń w obszarach gdzie jest ona przytwierdzona do kości za pomocą śrub. Wartości naprężeń zależą od rozmiaru płytki i śrub, miejsca zamocowań oraz obciążeń zewnętrznych działających na kość. Celem pracy było określenie przemieszczeń kości długiej stabilizowanej implantem przykostnym, szczególnie w rejonie złamania. Z uwagi na wykorzystaną metodę analizy przy okazji oszacowano wartości naprężeń występujących w kości. W oparciu o obrazy radiologiczne trzydziestu leczonych chorych, wykonano analizę obciążeń występujących w przypadku złamań o typie poprzecznym i skośnym. Uzyskano potwierdzenie biomechanicznej stabilności złamania przy stabilizacji nawet czasowej co najmniej sześcioma śrubami. Zwiększenie liczby śrub wpływa korzystnie na stabilizację, szczególnie w przypadku złamań skośnych. Liczba śrub jest jednak ograniczona z uwagi na możliwość zniszczenia struktury kości. Symulacja została przeprowadzona metodą elementów skończonych przy zastosowaniu pakietu komputerowego Ansys. Dla uproszczenia analiz oraz w celu przetestowania możliwości wykorzystania uproszczonego podejścia wykorzystany został model płaski. Możliwość zastosowania takiego modelu w analizach uproszczonych wynika z faktu, że najczęściej śruby mocujące płytkę do kości rozmieszczane są wzdłuż jednej linii w przybliżeniu równoległej do osi kości. Wyniki analiz wskazują, że model płaski wydaje się być wystarczająco dokładny do okołooperacyjnej oceny sposobu stabilizacji złamania, mając na uwadze krótki czas potrzebny do zbudowania modelu.

EN

Long bone fractures can be treated in several ways. One of them is using the paraosteal plate. The plate mounted to a bone enables the therapy process, but it can also be a source of extra stresses in the mounting regions. Values of stresses depend on the plates’ and screws’ dimensions, number of screws, the mounting place and external loads acting on the bone. The aim of this paper was to determine displacements of long bone stabilized by the paraosteal implant, especially in the fracture area. Due to applied method of analysis, the stresses value occurring in the bone were also estimated. Based on radiological images of thirty patients, an analysis of transverse and oblique fractures burthen was performed. The biomechanical fracture stabilization by even temporary stabilization with at least six screws was confirmed. Increasing the number of screws affects profitably the stabilization, especially in the case of oblique fractures. Number of screws is limited by possibility of damage of bone’s structure. The simulation was performed using a finite element method and application of the Ansys computer package. In order to simplify the analysis and to test the possibility of reduced attempt application, the plane model was applied. Possibility of application of such a model in simplified analyses is explained by the fact that usually the screws mounting plate to a bone are situated along one line parallel to the line of the bone axis. Results of the analysis show, that the plane model seems to be good enough to preoperative estimation of the way of fracture stabilization due to short time required to creation of the model.

6

An alternative approach for the interpretation of data from three-point bending of long bones

72%

Kourkoulis S. K. , Kouvaka A. , Andriakopoulou C. , Dontas I.

Engineering Transactions

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2016

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tom Vol. 64, iss. 4

401--407

EN

An alternative approach for elaborating the raw data obtained from three-point bending tests of long bones of Wistar rats is described. The aim of the study is to provide mechanical properties of the bone tissue which are independent of the bone geometric characteristics. The study is carried out experimentally ex vivo. It is indicated that ignoring the actual shape of the bone’s critical cross-section (i.e., the section where fracture occurs) and the inclination of the loading axis with respect to the principal centroidal axes of the critical section, may lead to erroneous results concerning the strength of the tissue.

7

Formation of synovial joints and articular cartilage

72%

Moskalewski S. , Hyc A. , Jankowska-Steifer E. , Osiecka-Iwan A.

Folia Morphologica

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2013

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tom 72

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nr 3

EN

Chondrocytes differentiate from mesenchymal progenitors and produce templates (anlagen) for the developing bones. Chondrocyte differentiation is controlled by Sox transcription factors. Templates for the neighbour bones are subsequently separated by conversion of differentiated chondrocytes into non-chondrogenic cells and emergence of interzone in which joints cavitation occurs. A central role in initiating synovial joint formation plays Wnt-14/beta-catenin signalling pathway. Moreover, bone morphogenetic proteins and growth and differentiation factors are expressed at the site of joint formation. Joint cavitation is associated with increased hyaluronic acid synthesis. Hyaluronic acid facilitates tissue separation and creation of a functional joint cavity. According to the traditional view articular cartilage represents part of cartilage anlage that is not replaced by bone through endochondral ossification. Recent studies indicate, however, that peri-joint mesenchymal cells take part in interzone formation and that these interzone cells subsequently differentiate into articular chondrocytes and synovial cells. Thus, anlage chondrocytes have a transient character and disappear after cessation of growth plate function while articular chondrocytes have stable and permanent phenotype and function throughout life. (Folia Morphol 2013; 72, 3: 181–187)

8

Prediction of displacement in the equine third metacarpal bone using a neural network prediction algorithm

72%

Mouloodi S. , Rahmanpanah H. , Burvill C. , Davies H. M. S.

Biocybernetics and Biomedical Engineering

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2020

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tom Vol. 40, no. 2

849--863

EN

Bone is a nonlinear, inhomogeneous and anisotropic material. To predict the behavior of bones expert systems are employed to reduce the computational cost and to enhance the accuracy of simulations. In this study, an artificial neural network (ANN) was used for the prediction of displacement in long bones followed by ex-vivo experiments. Three hydrated third metacarpal bones (MC3) from 3 thoroughbred horses were used in the experiments. A set of strain gauges were distributed around the midshaft of the bones. These bones were then loaded in compression in an MTS machine. The recordings of strains, load, load exposure time, and displacement were used as ANN input parameters. The ANN which was trained using 3,250 experimental data points from two bones predicted the displace-ment of the third bone (R2 ≥ 0.98). It was suggested that the ANN should be trained using noisy data points. The proposed modification in the training algorithm makes the ANN very robust against noisy inputs measurements. The performance of the ANN was evaluated in response to changes in the number of input data points and then by assuming a lack of strain data. A finite element analysis (FEA) was conducted to replicate one cycle of force-displace-ment experimental data (to gain the same accuracy produced by the ANN). The comparison of FEA and ANN displacement predictions indicates that the ANN produced a satisfactory outcome within a couple of seconds, while FEA required more than 160 times as long to solve the same model (CPU time: 5 h and 30 min).

9

Lipid peroxidation product 4-hydroxynonenal as factor of oxidative homeostasis supporting bone regeneration with bioactive glasses

72%

Mrakovcic L. , Wildburger R. , Jaganjac M. , Cindric M. , Cipak A. , Borovic Sunjic S. , Waeg G. , Milankovic A. M. , Zarkovic N.

Acta Biochimica Polonica

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2010

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tom 57

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nr 2

EN

Bone regeneration is a process of vital importance since fractures of long bones and large joints have a highly deleterious impact on both, individuals and society. Numerous attempts have been undertaken to alleviate this severe medical and social problem by development of novel bioactive materials, among which bioactive glass is the most attractive because of its osteoconductive and osteostimulative properties. Since lipid peroxidation is an important component of systematic stress response in patients with traumatic brain injuries and bone fractures, studies have been undertaken of the molecular mechanisms of the involvement of 4-hydroxynonenal (HNE), an end product of lipid peroxidation, in cellular growth regulation. We found that HNE generated in bone cells grown in vitro on the surfaces of bioactive glasses 45S5 and 13-93. This raises an interesting possibility of combined action of HNE and ionic bioglass dissolution products in enhanced osteogenesis probably through a mitogen-activated protein kinase (MAPK) pathway. While the proposed mechanism still has to be elucidated, the finding of HNE generation on bioglass offers a new interpretation of the osteoinducting mechanisms of bioglass and suggests the possibility of tissue engineering based on manipulations of oxidative homeostasis.

10

Analyzing ungulate long bones as a tool for habitat reconstruction

72%

Schellhorn R. , Pfretzschner H.-U.

Acta Theriologica

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2015

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tom 60

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nr 2

EN

The long bones (humerus, radius, metacarpus, femur, tibia, metatarsus) of 51 extant bovid and 7 equid specimens were measured in order to test the hypothesis that they show adaptations to different habitats. We performed factor analyses (FAs) with principal component extraction method and plotted the extracted factors (Fs) in simple scatterplots. The preferred habitats (grassland, forest, mountainous regions) were labeled in the plots, and our results show three clearly separated clusters for F2 vs. F3. According to our interpretation, F1 reflects the body size of the specimens while F2 is most probably reflecting cursorial adaptations. F3 is largely affected by dimensional bone characteristics adapted to maneuver in the environment, and therefore, F3 is somehow linked to habitat. The investigated equids are plotting within the cluster of bovids preferring grassland habitats, which is surprising because of different constructions of the metapodials in perissodactyls and ruminants. Performed linear discriminant analyses (LDAs) are supporting our FA results. This approach combines biometrics with statistics and presents a tool, which easily can be applied helping to identify the paleo-habitat or the paleo-ecology of extinct bovids with implications on fossil localities.

11

Development of the innervation of long bones: expression of the growth-associated protein 43

72%

Gajda M. , Adriaensen D. , Cichocki T.

Folia Histochemica et Cytobiologica

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2000

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tom 38

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nr 3

12

Analysis of some biophysical and biochemical parameters of long bones of spiny mouse [Acomys cahirinus] in its life cycle

72%

Niedzwiedz M. , Gawron A. , Korczak W. , Trebacz H.

Folia Histochemica et Cytobiologica

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1999

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tom 37

|

nr 2

13

Podstawowe zagadnienia dotyczące diagnostyki i planowania przedzabiegowego złamań kości długich u zwierząt towarzyszących

58%

Nowicki M. , Glodek J. , Adamiak Z.

Weterynaria w Praktyce

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2020

|

tom 17

|

nr 03

14

The first dsungaripterid pterosaur from the Kimmeridgian of Germany and the biomechanics of pterosaur long bones

58%

Fastnacht M.

Acta Palaeontologica Polonica

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2005

|

tom 50

|

nr 2

EN

A partial vertebral column, pelvis and femora of a newly discovered pterosaur are described. The remains from the Upper Jurassic (Kimmeridgian) of Oker (northern Germany) can be identified as belonging to the Dsungaripteridae because the cross−sections of the bones have relatively thick walls. The close resemblance in morphology to the Lower Cretaceous Dsungaripterus allows identification of the specimen as the first and oldest record of dsungaripterids in Central Europe. Furthermore, it is the oldest certain record of a dsungaripterid pterosaur world wide. The biomechanical characteristics of the dsungaripterid long bone construction shows that it has less resistance against bending and torsion than in non−dsungaripteroid pterosaurs, but has greater strength against compression and local buckling. This supports former suggestions that dsungaripterids inhabited continental areas that required an active way of life including frequent take−off and landing phases. The reconstruction of the lever arms of the pelvic musculature and the mobility of the femur indicates a quadrupedal terrestrial locomotion.

15

Damage to Pigeon long bones in pellets of the Eagle Owl Bubo bubo and food remains of Peregrine Falcon Falco peregrinus: zooarchaeological implications

58%

Laroulandie V.

Acta Zoologica Cracoviensia

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2002

|

tom 45

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nr Spec.issue

16

Ancient avian osteopetrosis: the current state of knowledge

58%

Brothwell D.

Acta Zoologica Cracoviensia

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2002

|

tom 45

|

nr Spec.issue