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1.
Polymers (Basel) ; 16(15)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39125249

RESUMEN

Thermoplastic composite organosheets (OSs) are increasingly recognized as a viable solution for automotive and aerospace structures, offering a range of benefits including cost-effectiveness through high-rate production, lightweight design, impact resistance, formability, and recyclability. This study examines the impact response, post-impact strength evaluation, and hot-pressing repair effectiveness of woven glass fiber nylon composite OSs across varying impact energy levels. Experimental investigations involved subjecting composite specimens to impact at varying energy levels using a drop-tower test rig, followed by compression-after-impact (CAI) tests. The results underscore the exceptional damage tolerance and improved residual compressive strength of the OSs compared to traditional thermoset composites. This enhancement was primarily attributed to the matrix's ductility, which mitigated transverse crack propagation and significantly increased the amount of absorbed energy. To mitigate impact-induced damage, a localized hot-pressing repair approach was developed. This allowed to restore the post-impact strength of the OSs to pristine levels for impact energies below 40 J and by 83.6% for higher impact energies, when OS perforation was observed. The measured levels of post-repair strength demonstrate a successful restoration of OS strength over a wide range of impact energies, and despite limitations in achieving complete strength recovery above 40 J, hot-pressing repair emerges as a promising strategy for ensuring the longevity of thermoplastic composites through repairability.

2.
Anat Rec (Hoboken) ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010732

RESUMEN

Analyses of the cetacean (whale and dolphin) inner ear provide glimpses into the ecology and evolution of extinct and extant groups. The paleoecology of the long-snouted odontocete (toothed whale) group, Parapontoporia, is primarily marine with its depositional context also suggesting freshwater tolerance. As an extinct relative of the exclusively riverine Lipotes vexillifer, Parapontoporia provides insight into a transition from marine to freshwater environments. High-resolution X-ray CT scans (~3 microns or less) of three individual specimens from two species, P. sternbergi and P. pacifica, were acquired. Digital endocasts of the inner ear labyrinths were extracted non-destructively. Nine measurements of the inner ear were compared with an existing dataset covering 125 terrestrial and aquatic artiodactyls. These measurements were then subjected to a principal component analysis to interpret hearing sensitivities among other artiodactyls. Based on our analyses, Parapontoporia was likely to have been able to hear within narrow-band high frequency (NBHF) ranges. This finding indicates another convergence of NBHF-style hearing, or, more intriguingly, suggests that it may be an ancestral characteristic present among the longirostrine dolphins that dominated in the Miocene prior to the evolution of more modern lineages.

3.
Development ; 151(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38940461

RESUMEN

The vertebral column is a characteristic structure of vertebrates. Genetic studies in mice have shown that Hox-mediated patterning plays a key role in specifying discrete anatomical regions of the vertebral column. Expression pattern analyses in several vertebrate embryos have provided correlative evidence that the anterior boundaries of Hox expression coincide with distinct anatomical vertebrae. However, because functional analyses have been limited to mice, it remains unclear which Hox genes actually function in vertebral patterning in other vertebrates. In this study, various zebrafish Hox mutants were generated for loss-of-function phenotypic analysis to functionally decipher the Hox code responsible for the zebrafish anterior vertebrae between the occipital and thoracic vertebrae. We found that Hox genes in HoxB- and HoxC-related clusters participate in regulating the morphology of the zebrafish anterior vertebrae. In addition, medaka hoxc6a was found to be responsible for anterior vertebral identity, as in zebrafish. Based on phenotypic similarities with Hoxc6 knockout mice, our results suggest that the Hox patterning system, including at least Hoxc6, may have been functionally established in the vertebral patterning of the common ancestor of ray-finned and lobe-finned fishes.


Asunto(s)
Tipificación del Cuerpo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio , Columna Vertebral , Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/embriología , Columna Vertebral/embriología , Tipificación del Cuerpo/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Genes Homeobox/genética , Oryzias/genética , Oryzias/embriología , Ratones
4.
Zoolog Sci ; 41(3): 281-289, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38809867

RESUMEN

Platyhelminthes are a phylum of simple bilaterian invertebrates with prototypic body systems. Compared with non-bilaterians such as cnidarians, the bilaterians are likely to exhibit integrated free-moving behaviors, which require a concentrated nervous system "brain" rather than the distributed nervous system of radiatans. Marine flatworms have an early cephalized 'central' nervous system compared not only with non-bilaterians but also with parasitic flatworms or freshwater planarians. In this study, we used the marine flatworm Stylochoplana pusilla as an excellent model organism in Platyhelminthes because of the early cephalized central nervous system. Here, we investigated the three-dimensional structures of the flatworm central nervous system by the use of X-ray micro-computed tomography (micro-CT) in a synchrotron radiation facility. We found that the obtained tomographic images were sufficient to discriminate some characteristic structures of the nervous system, including nerve cords around the cephalic ganglion, mushroom body-like structures, and putative optic nerves forming an optic commissure-like structure. Through the micro-CT imaging, we could obtain undistorted serial section images, permitting us to visualize precise spatial relationships of neuronal subpopulations and nerve tracts. 3-D micro-CT is very effective in the volume analysis of the nervous system at the cellular level; the methodology is straightforward and could be applied to many other non-model organisms.


Asunto(s)
Sistema Nervioso Central , Platelmintos , Microtomografía por Rayos X , Animales , Microtomografía por Rayos X/veterinaria , Platelmintos/anatomía & histología , Platelmintos/clasificación , Sistema Nervioso Central/diagnóstico por imagen , Sistema Nervioso Central/anatomía & histología
5.
Toxicon ; 234: 107285, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37683698

RESUMEN

Oral and other cephalic glands have been surveyed by several studies with distinct purposes. Despite the wide diversity and medical relevance of the New World coral snakes, studies focusing on understanding the biological roles of the glands within this group are still scarce. Specifically, the venom glands of some coral snakes were previously investigated but all other cephalic glands remain uncharacterized. In this sense, performing morphological and molecular analysis of these glands may help better understand their biological role. Here, we studied the morphology of the venom, infralabial, rictal, and harderian glands of thirteen species of Micrurus and Micruroides euryxanthus. We also performed a molecular characterization of these glands from selected species of Micrurus using transcriptomic and proteomic approaches. We described substantial morphological variation in the cephalic glands of New World coral snakes and structural evidence for protein-secreting cells in the inferior rictal glands. Our molecular analysis revealed that the venom glands, as expected, are majorly devoted to toxin production, however, the infralabial and inferior rictal glands also expressed some toxin genes at low to medium levels, despite the marked morphological differences. On the other hand, the harderian glands were dominated by the expression of lipocalins, but do not produce toxins. Our integrative analysis, including the prediction of biological processes and pathways, helped decipher some important traits of cephalic glands and better understand their biology.

6.
Materials (Basel) ; 16(16)2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37629962

RESUMEN

In this study, the sound absorption coefficients of rice and buckwheat husks were estimated. Computed tomography (CT) images were processed to determine the circumference and surface area of voids in the granular material, and the normal incident sound absorption coefficients were derived. In addition, the tortuosity, which expresses the complexity of the sound wave propagation through the structure, was measured for each material. The theoretical sound absorption coefficients were then compared to the measured sound absorption coefficients with and without consideration of the tortuosity. A correction factor was used to bring the surface area of the granular material closer to the actual surface area and observed that the tortuosity obtained theoretical values that matched the trend of the measured values. These results indicate that using CT images to estimate the sound absorption coefficient is a viable approach.

7.
Zoology (Jena) ; 159: 126102, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37364349

RESUMEN

The batracoidid Plainfin Midshipmen Porichthys notatus Girard has been extensively studied due to the sound production abilities and specializations of its swim bladder. The present study describes three-dimensional variations of the morphology of the swim bladder and sonic muscles of P. notatus during its post-hatch larval development, with the use of three-dimensional computed tomography. This study also includes descriptions of the relative position of the swim bladder to other visceral organs. The swim bladder, digestive tract, and liver were already present in the smallest examined specimens (5.9 mm; newly hatched larvae) along with the yolk sac. In the smallest specimens, the digestive tract is straight, but from 7.1 mm TL, the digestive tract forms the first intestinal loops, and at 25.5 mm TL, a second intestinal loop. In smallest specimens, the swim bladder is oval, but at 7.1 mm TL, the anterior margin starts invaginating, forming a pair of anterior lobes. The first appearance of the intrinsic sonic muscles in swim bladder occurs at 13.1 mm TL. Additionally, we provide comparisons between the shape of the swim bladder of P. notatus and other species. The shape of the swim bladder of P. notatus and other members of Porichthyinae have an ovoid posterior region with two anterior lobes and differs from the cordiform or semiconected/bilobed the swim bladders observed in the other Batrachoididae.


Asunto(s)
Batrachoidiformes , Animales , Batrachoidiformes/anatomía & histología , Batrachoidiformes/fisiología , Vejiga Urinaria , Sonido
8.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36769339

RESUMEN

Scientific examination of the heart of Blessed Pauline Jaricot-a French missionary figure-was carried out in 2022. As tandem mass spectrometry proteotyping has proven to be valuable to obtain the broad taxonomic repertoire of a given sample without any a priori information, we aimed at exploring the conditions of preservation of the relics and possible conditions of death. Metaproteomics and high-resolution microtomography imaging approaches were combined. A dataset comprising 6731 high-resolution MS/MS spectra was acquired and 968 of these spectra could be assigned to specific peptidic biomolecules. Based on the taxonomical information encompassed by the identified peptide sequences, 5 phyla were identified amongst eukaryota (94% of the biomass): Ascomycota (55%), with the species Aspergillus versicolor, Trichophyton mentagrophytes and Aspergillus glaucus, corresponding to expected cadaverous fungal flora; Chordata (42%), represented by a unique species, Homo sapiens; Streptophyta (3%); and Arthropoda (traces). Bacteria (6% of the biomass) were poorly represented. No trace of embalming substance could be retrieved, nor any pathogens. Imaging evidenced no heart defect nor embalming traces. No evidence that was inconsistent with natural and spontaneous conservation could be retrieved. This study prefigures the power of modern molecular techniques such as paleoproteotyping coupled to microtomography to gain insight into historical relics.


Asunto(s)
Embalsamiento , Cardiopatías Congénitas , Humanos , Embalsamiento/métodos , Espectrometría de Masas en Tándem , Corazón , Bacterias
9.
Int J Paleopathol ; 38: 41-44, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35809435

RESUMEN

OBJECTIVE: This paper presents the inner ear modifications in Dar-es-Soltane II H5, an Aterian fossil possibly dated to 100 ka. MATERIAL: The remains consist of a large portion of the cranium including the face, the left frontal and temporal bones, part of the left parietal bone and greater wing of the sphenoid. METHODS: The bony labyrinth anatomy was investigated on existing micro-CT data acquired by the MPI-EVA. RESULTS: The observation of micro-CT sections revealed a partial filling of the semi-circular canals that raises question about its origin. A careful examination of the micro-CT sections shows that the elements present in the semicircular canals were denser than the sediments observed in other regions and cavities of the temporal bone. CONCLUSIONS: The current evidence suggests a pathological origin of this condition with partial ossification of the membranous labyrinth. The differential diagnosis indicates a case of labyrinthitis ossificans in its early stages. SIGNIFICANCE: This pathological condition can be responsible for permanent hearing loss and is associated with dizziness and vertigo. Along with the Singa skull, Dar-es-Soltane II H5 represents one of the oldest known cases of labyrinthitis ossificans. LIMITATIONS: The early stage of disease and the absence of the right temporal bone limit conclusions about the degree of disability of the individual and their dependence on the rest of the group. SUGGESTIONS FOR FURTHER RESEARCH: To carry out a paleopathological study of all the fossils from Dar-es-Soltane II.


Asunto(s)
Oído Interno , Laberintitis , Osificación Heterotópica , Oído Interno/patología , Humanos , Laberintitis/complicaciones , Laberintitis/patología , Marruecos , Osificación Heterotópica/patología , Hueso Temporal/patología
10.
J Oral Biol Craniofac Res ; 12(4): 444-448, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35664952

RESUMEN

Background: The aim of the study was to compare the efficacy of different irrigation and irrigant activation system used as an adjuvant to retreatment rotary files in removal of gutta-percha and sealer from endodontic retreatment using Micro-CT. Method: 64 extracted permanent maxillary central incisor teeth with single canal, were collected and decoronated to standard length of 16 mm. Instrumentation was done using rotary files and obturation was performed using GuttaCore and AH plus sealer. After setting of sealer, initial removal of filling material was performed using ProTaper universal retreatment files (D1, D2, D3). All 64 sample were randomised into four groups (n = 16) Group1: Endodontic syringe irrigation, Group 2: Passive Ultasonic Irrigation (PUI), Group 3: EndoActivator, and Group 4: EndoVac. Micro-CT scanning was performed after obturation, initial removal of filling material by retreatment file and after using experimental protocols of each group, and volume of remaining filling material was calculated using Dolphin software. Statistical analysis performed with one-way ANOVA followed by Tukey's post hoc. Results: A significant reduction in the volume of residual obturation material were found between each group. PUI was superior to the sonic (EndoActivator), negative pressure irrigation technique (EndoVac) and positive pressure irrigation at the coronal, middle third and apical third of the root canal. However, none of the supplementary techniques were able to completely remove the residual obturation material. Conclusion: PUI and EndoActivator were found better in remaining filling material removal, demonstrating clinically useful as supplementary technique in removing remaining obturation material during endodontic retreatment.

11.
J Esthet Restor Dent ; 34(4): 707-714, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35294099

RESUMEN

OBJECTIVE: To compare the marginal and internal adaptation of endocrowns produced using conventional technique, digital technique, and combination (cast digitization) techniques using microcomputed tomography (micro-CT). MATERIALS AND METHODS: Ten freshly extracted human mandibular molar teeth were prepared for all-ceramic endocrowns. A total of 40 Lithium Disilicate (IPS e.max) endocrowns were fabricated and grouped according to the impression and production technique to four groups: Group (CO): Conventional impression/heat pressed endocrowns (n = 10), Group (CAD): Direct scanning of teeth/CAD-CAM endocrowns (n = 10), Group (COMIO): Combination; Cast digitization using Intraoral scanner/CAD-CAM endocrowns (n = 10), Group (COML): Combination; Cast digitization using laboratory scanner/CAD-CAM endocrowns (n = 10). Micro-computed tomography was used to measure the marginal and internal gaps in 11 predetermined sites. Mean marginal and internal gaps were compared using analysis of variance and Scheffe's post hoc test. RESULTS: CO, CAD, COMIO, and COML groups showed significant differences in the mean marginal gap (150 ± 35 µm, 120 ± 27 µm, 110 ± 24 µm, 120 ± 29 µm, respectively p = 0.013), gap at line angle (280 ± 70 µm, 130 ± 37 µm, 140 ± 54 µm, 130 ± 33 µm, respectively, p < 0.001), gap at cavity wall (210 ± 76 µm, 140 ± 43 µm, 140 ± 52 µm, 150 ± 44 µm, respectively, p = 0.010) and gap at pulpal floor (500 ± 150 µm, 240 ± 58 µm, 260 ± 59 µm, 240 ± 64 µm, respectively, p < 0.001). CONCLUSION: Digitally fabricated endocrowns showed superior marginal and internal fit compared to the conventionally fabricated endocrowns. CLINICAL SIGNIFICANCE: Marginal and internal adaptation are detrimental factors for the success and survival of dental restorations including endocrowns. When compared with the conventional impressions and conventional production techniques, Digital workflow is more predictable and reliable as it reduces errors and improves the accuracy of fit.


Asunto(s)
Adaptación Marginal Dental , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Coronas , Técnica de Impresión Dental , Porcelana Dental , Diseño de Prótesis Dental/métodos , Humanos , Microtomografía por Rayos X/métodos
12.
Materials (Basel) ; 16(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36614676

RESUMEN

In this study, the sound absorption properties of randomly packed granular materials were estimated. Generally, it is difficult to construct a general mathematical model for the arrangement of randomly packed granular materials. Therefore, in this study, an attempt was made to estimate the sound absorption coefficient using a theoretical analysis by introducing data from computed tomography (CT) scans, as the tomographic images of CT scans correspond to the slicing and elemental division of packing structures. In the theoretical analysis, the propagation constants and characteristic impedances in the voids were obtained by approximating each tomographic image as a void between two parallel planes. The derived propagation constants and characteristic impedances were then treated as a one-dimensional transfer matrix in the propagation of sound waves, and the transfer matrix method was used to calculate the normal incident sound absorption coefficient. The theoretical value of the sound absorption coefficient was derived using the effective density to which the measured tortuosity was applied. As a result, for the theoretical values considering the tortuosity, in many cases, the theoretical values were close to the measured values. For the theoretical values, when both the surface area and tortuosity were considered, the peak sound absorption frequency moved to a lower frequency and was in general agreement with the measured values.

13.
Anat Rec (Hoboken) ; 305(11): 3113-3132, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-34779131

RESUMEN

Irajatherium hernandezi is a poorly known non-mammaliaform cynodont from the Late Triassic of southern Brazil. A new specimen of this cynodont was found in recent fieldwork to the type-locality, Sesmaria do Pinhal (Candelária), providing new insights into the anatomy of this mammalian forerunner. This specimen comprises a partial skull preserving the left canine, two left and three right postcanines, and an isolated exoccipital; the left dentary with the canine and postcanines; a fragment of the right dentary; the proximal portion of the left partial humerus; the right scapula; and indeterminate fragments. Based on new material, it is here suggested that I. hernandezi presents: a rostrum broad and short, possibly long as the temporal region; three foramina on the lateral surface of the maxilla, that could correspond to the external openings of the rostral alveolar, infraorbital, and zygomaticofacial canals; a slender zygomatic arch and an absent postorbital bar; a posteriorly wide temporal fossa; a long secondary palate, slightly surpassing the level of the last postcanine tooth; the cerebral hemispheres of the cranial endocast divided by a median sulcus; the scapular blade long and straight, and the postscapular fossa absent in lateral aspect. Finally, I. hernandezi and other tritheledontids were included in a phylogenetic analysis of Eucynodontia. The analysis recovered unresolved relationships for ictidosaurs/tritheledontids, nested within a polytomy with Tritylodontidae and a clade composed by Pseudotherium argentinus, Botucaraitherium belarminoi, Brasilodon quadrangularis, and Mammaliaformes.


Asunto(s)
Fósiles , Cráneo , Animales , Brasil , Mamíferos/anatomía & histología , Filogenia , Cráneo/anatomía & histología
14.
Heliyon ; 7(2): e06307, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33681499

RESUMEN

The polychaete Diopatra claparedii Grube, 1878 is among those organisms successfully carrying out full body regeneration, including the whole nervous system. Thus, D. claparedii potentially can be regarded for the nervous system regeneration (NSR) study. However, data on the property of its nervous system and the NSR profile are still lacking. In this study, we investigated the morphology of D. claparedii anterior nervous system (ANS) and examined the cellular and molecular profiles on its early anterior NSR. The nervous system of D. claparedii consists of a symmetry brain with nerves branching off, circumpharyngeal connectives that connect the brain and nerve cord as well as obvious segmental ganglia. Moreover, we identified changes in the cellular condition of the ganglionic cells in the regenerating tissue, such as the accumulation of lysosomes and lipofuscins, elongated mitochondria and multiple nucleoli. Furthermore, mRNA of tissues at two regenerating stages, as well as intact tissue (non-regenerating), were sequenced with Illumina sequencer. We identified from these tissues 37,248 sequences, 18 differential expressed proteins of which upregulated were involved in NSR with noelin-like isoform X2 turned up to be the highest being expressed. Our results highlight the cellular and molecular changes during early phase of NSR, thus providing essential insights on regeneration within Annelida and understanding the neurodegenerative diseases.

15.
Clin Kidney J ; 14(1): 398-407, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33564444

RESUMEN

BACKGROUND: Different strategies can be used to counteract coagulation of extracorporeal systems. Systemic anticoagulation is most widely used in routine clinical practice, but can be contraindicated in specific settings. The Solacea™ dialyser, containing the asymmetric triacetate membrane, claims improved biocompatibility, which should result in decreased tendency for coagulation. We quantified the performance of the Solacea™ versus the FX800CORDIAX dialyser regarding resistance to fibre blocking as assessed by micro-computed tomography (CT). METHODS: This cross-over study with four arms randomized consecutively 10 maintenance haemodialysis patients to a 4-h post-dilution haemodiafiltration session at midweek, using either Solacea™ 19 H or FX800CORDIAX, with either regular or half dose of anticoagulation (EC2017/1459-NCT03820401). Dialyser fibre blocking was visualized in the dialyser outlet potting using a 3D CT scanning technique on micrometre resolution. Extraction ratios of middle molecules [myoglobin, lambda and kappa free light chains (FLCs)] were determined. RESULTS: The relative number of open fibres post-dialysis was lower in FX800CORDIAX versus Solacea™ dialyser, and this was irrespective of the anticoagulation dose used or the threshold for counting open fibres. Extraction ratios of FLCs were not different at regular anticoagulation between Solacea™ and FX800CORDIAX (21% ± 4% for kappa and 32% ± 8% for lambda with Solacea™ versus 23% ± 7% and 38% ± 6% for FX800CORDIAX), but were superior with the Solacea™ (34% ± 12% versus 22% ± 8% with FX800CORDIAX; P = 0.02) for myoglobin in case of halving anticoagulation dose. No clinically relevant albumin loss was detected. CONCLUSIONS: The Solacea™ dialyser seems to be promising for use in conditions where systemic anticoagulation is contraindicated, as even under conditions of low systemic anticoagulation, virtually no signs of fibre blocking could be observed using the sensitive micro-CT scanning technique. This finding is in line with its presumed good performance in terms of biocompatibility.

17.
Clin Biomech (Bristol, Avon) ; 51: 1-9, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29132027

RESUMEN

BACKGROUND: During implantation of an uncemented femoral knee implant, press-fit interference fit provides the primary stability. It is assumed that during implantation a combination of elastic and plastic deformation and abrasion of the bone will occur, but little is known about what happens at the bone-implant interface and how much press-fit interference fit is eventually achieved. METHODS: Five cadaveric femora were prepared and implantation was performed by an experienced surgeon. Micro-CT- and conventional CT-scans were obtained pre- and post-implantation for geometrical measurements and to measure bone mineral density. Additionally, the position of the implant with respect to the bone was determined by optical scanning of the reconstructions. By measuring the differences in surface geometry, assessments were made of the cutting error, the actual interference fit, the amount of bone damage, and the effective interference fit. FINDINGS: Our analysis showed an average cutting error of 0.67mm (SD 0.17mm), which pointed mostly towards bone under-resections. We found an average actual AP interference fit of 1.48mm (SD 0.27mm), which was close to the nominal value of 1.5mm. INTERPRETATION: We observed combinations of bone damage and elastic deformation in all bone specimens, which showed a trend to be related with bone density. Higher bone density tended to lead to lower bone damage and higher elastic deformation. The results of the current study indicate different factors that interact while implanting an uncemented femoral knee component. This knowledge can be used to fine-tune design criteria of femoral components to achieve adequate primary stability for all patients.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Interfase Hueso-Implante , Cabeza Femoral/patología , Cabeza Femoral/cirugía , Prótesis de la Rodilla , Anciano de 80 o más Años , Cementos para Huesos , Densidad Ósea , Femenino , Cabeza Femoral/diagnóstico por imagen , Humanos , Articulación de la Rodilla , Masculino , Microtomografía por Rayos X
18.
Tissue Eng Part C Methods ; 23(12): 964-970, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28806898

RESUMEN

Tissue engineering technologies are new and promising techniques in fat tissue reconstruction. However, to assess their efficacy before any clinical application, in vivo experiments are mandatory. This study assesses whether microcomputed tomography (CT) scan imaging is suitable to analyze in vivo the behavior of injected engineered polymer and changes in fat tissue. The volume of mice inguinal fat pads and the resorption rate of different polymers were analyzed by CT scan for up to 3 months. Different biomaterials were used, including our innovative microspheres loaded with oleic acid. We were able to follow in vivo the polymer and the fat volume of the same animals during a long-term follow-up of 90 days. Semiautomatic three-dimensional quantification allowed to determine the fat volume enhancement after injection, as well as the resorption rate of our product compared to other biomaterials (i.e., polylactic and hyaluronic acid) until 90 days. Our results demonstrate the encouraging proof-of-principle evidence for the application of micro-CT scan technology to follow in vivo biodegradable polymers in a fat tissue engineering approach. This noninvasive technique offers the advantages of the long-term follow-up of fat tissue and synthetic materials in the same animals, which allows both a scientific evaluation of the measurements and the reduction of the number of animals used in in vivo protocols in accordance with the 3 "R" principles governing the use of animals in science.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Imagenología Tridimensional , Inyecciones , Polímeros/administración & dosificación , Microtomografía por Rayos X , Animales , Femenino , Conducto Inguinal/diagnóstico por imagen , Ratones Endogámicos BALB C , Microesferas , Tamaño de los Órganos
19.
J Exp Clin Cancer Res ; 35(1): 155, 2016 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-27686696

RESUMEN

BACKGROUND: Genetically induced hepatocellular carcinoma (HCC) models are generally used to investigate carcinogenesis pathways, but very few attempts were made to valorize them for pharmacological testing. This study describes a micro-computed tomography (micro-CT) - based methodology for the diagnostic and lifelong follow-up of HCC in the hepatocyte-specific Trim24-null mouse line. Myo-inositol trispyrophosphate (ITPP) was tested as anti-cancer drug. METHODS: Partial hepatectomy was performed in 2 months-old Trim24-null mice, in order to accelerate the carcinogenesis process. HCC diagnosis was obtained by micro-CT scan with double contrast agent: 10 µl/g Fenestra™ LC was injected intraperitoneally 6 h prior to imaging and 10 µl/g Fenestra™ VC was injected intravenously 15 min prior to imaging. Twenty three hepatocyte-specific Trim24-null mice were considered for ITPP testing (3 mg/g/week intraperitoneally during 10 months in 12 mice, versus 11 controls). Lifelong follow-up was performed using micro-CT. Comparative analysis was performed using unpaired t test with Welch correction and survival curves were compared by log-rank test. Gene expression analysis was performed using the RT q-PCR technique. RESULTS: Double contrast micro-CT scan allowed HCC diagnosis as hypodense, isodense or hyperdense nodules. Positive predictive value was 81.3 %. Negative predictive value was 83.3 %. Tumor growth could be objectified by micro-CT scan before the ITPP treatment was started, and at 3 and 9 months follow-up. Significant progression of tumor volume was demonstrated in the both groups, with no difference between groups (p > 0.05). In the ITPP group, a mild decrease in tumor doubling time was first observed (31.9 +/- 12 days, p > 0.05) followed by a significant increase (59.8 +/- 18.3 days, p = 0.008). However, tumor doubling time was not different between groups (p > 0.05). Median survival after treatment initiation was 223 days (controls) versus 296 days (ITPP group, p = 0.0027). HIF1α, VEGF, glutamine synthase, osteopontin expression levels were not significantly modified at the end of follow-up. In the ITPP group, the p53 expression profile was inversed as compared to the control group, higher in non-tumor livers than in tumors. CONCLUSION: ITPP treatment allowed for a two-month survival improvement, with better tolerance of tumor burden and apoptosis increase in non-tumor, pathological livers.

20.
J Wrist Surg ; 5(2): 105-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27104074

RESUMEN

We report a patient with stage IIIB Kienböck disease treated with radial shortening where preoperative and sequential postoperative imaging were done using in vivo high-resolution peripheral quantitative micro-computed tomography (micro-CT) scan. Sequential in vivo micro-CT scan analysis of a target zone of the Kienböck lunate of this patient demonstrated early signs of lunate remodeling (bone trabecular densification) at 5-month follow-up suggesting an ongoing healing process. These early remodeling micro-CT scan signs were confirmed at 5 years' follow-up as well.

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