Different Animals (different + animals)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Consistent dynamics suggests tight regulation of biophysical parameters in a small network of bursting neurons

DEVELOPMENTAL NEUROBIOLOGY, Issue 14 2006
Attila Szücs
Abstract The neuronal firing patterns in the pyloric network of crustaceans are remarkably consistent among animals. Although this characteristic of the pyloric network is well-known, the biophysical mechanisms underlying the regulation of the systems output are receiving renewed attention. Computer simulations of the pyloric network recently demonstrated that consistent motor output can be achieved from neurons with disparate biophysical parameters among animals. Here we address this hypothesis by pharmacologically manipulating the pyloric network and analyzing the emerging voltage oscillations and firing patterns. Our results show that the pyloric network of the lobster stomatogastric ganglion maintains consistent and regular firing patterns even when entire populations of specific voltage-gated channels and synaptic receptors are blocked. The variations of temporal parameters used to characterize the burst patterns of the neurons as well as their intraburst spike dynamics do not display statistically significant increase after blocking the transient K-currents (with 4-aminopyridine), the glutamatergic inhibitory synapses (with picrotoxin), or the cholinergic synapses (with atropine) in pyloric networks from different animals. These data suggest that in this very compact circuit, the biophysical parameters are cell-specific and tightly regulated. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source]


Electrophoretically mediated microanalysis for the evaluation of interspecies variation in cholinesterase metabolism

ELECTROPHORESIS, Issue 14 2010
Joana Moura
Abstract This study describes an electrophoretically mediated microanalysis method, suitable for the preclinical evaluation of the hydrolysis of ester drugs by the serum of different animals and for further characterization of human,animal correlation. Dog, cat, cow, horse, sheep, rat and human serum were diluted (25%) in the appropriate buffer and replaced the enzyme solution usually used in electrophoretically mediated microanalysis methods for the study of enzyme kinetics. They were then compared in terms of the ability to hydrolyze acetylthiocholine and butyrylthiocholine (0.25,mM) by in-capillary reaction. Human serum afforded the highest conversion rates (52% butyryltiocholine and 34% acetylthiocholine) followed by horse (31 and 35%), dog (26 and 24%), cat (22 and 14%), rat (11 and 15%) and sheep (8 and 8%). Hydrolysis by bovine serum was negligible. The method is fast (under 8,min including rinsing steps), sensitive (under 25,,M substrate could be quantified) and repeatable (RSD,2%), only requiring minute amounts of sample. [source]


Trying to See Red Through Stickleback Photoreceptors: Functional Substitution of Receptor Sensitivities

ETHOLOGY, Issue 3 2006
Mickey P. Rowe
A key to understanding animal behavior is knowledge of the sensory information animals extract from their environment. For visually motivated tasks, the information animals obtain through their eyes is often assumed to be essentially the same as that perceived by humans. However, known differences in structure and processing among the visual systems of different animals clearly indicate that the world seen by each is different. A well-characterized difference between human and other animal visual systems is the number of types and spectral sensitivities of their photoreceptors. We are developing a technique, functional substitution, that exploits knowledge of these differences to portray for human subjects, colors as they would appear through the photoreceptors of another animal. In a specific application, we ask human subjects to rank hues of male threespine stickleback (Gasterosteus aculeatus) throats viewed through stickleback photopigments. We compare these ranks to ranks of the same throat hues viewed through normal human photoreceptors. We find essentially no difference between the two sets of rankings. This suggests that any differences in human and stickleback rankings of such hues would result from differences in post-receptoral neural processing. Using a previously developed model of stickleback neural processing, we established another ranking of the hues which was again essentially the same as the rankings produced by the human subjects. A growing literature indicates that stickleback do rank such hues in the evaluation of males as potential mates or threats. Although our results do not demonstrate that humans and stickleback use the same mechanisms to assess color, our experiments significantly failed to show that stickleback and human rankings of throat hues should be different. Nevertheless, a comparison of all these rankings to ranks derived from subjective color scoring by human observers suggests that color scoring may utilize other cues and should thus be used cautiously. [source]


Differential sensitivity to calciseptine of L-type Ca2+ currents in a ,lower'vertebrate (Scyliorhinus canicula), a protochordate (Branchiostoma lanceolatum) and an invertebrate (Alloteuthis subulata)

EXPERIMENTAL PHYSIOLOGY, Issue 6 2001
Candida M. Rogers
Voltage-dependent calcium currents in vertebrate (Scyliorhinus canicula), protochordate (Branchiostoma lanceolatum), and invertebrate (Alloteuthis subulata) skeletal and striated muscle were examined under whole-cell voltage clamp. Nifedipine (10 ,M) suppressed and cobalt (5 mM) blocked striated/skeletal muscle calcium currents in all of the animals examined, confirming that they are of the L-type class. Calciseptine, a specific blocker of vertebrate cardiac muscle and neuronal L-type calcium currents, was applied (0.2 ,M) under whole-cell voltage clamp. Protochordate and invertebrate striated muscle L-type calcium currents were suppressed while up to 4 ,M calciseptine had no effect on dogfish skeletal muscle L-type calcium currents. Our results demonstrate the presence of at least two sub-types of L-type calcium current in these different animals, which may be distinguished by their calciseptine sensitivity. We conclude that the invertebrate and protochordate L-type current sub-type that we have examined has properties in common with vertebrate ,cardiac' and ,neuronal' current sub-types, but not the skeletal muscle sub-type of the L-type channel. [source]


Zoonotic risk of hepatitis E virus (HEV): A study of HEV infection in animals and humans in suburbs of Beijing

HEPATOLOGY RESEARCH, Issue 12 2009
Yibin Chang
Aim:, To investigate hepatitis E virus (HEV) infection among different animals and workers in pig farms and slaughterhouses, and analyze the genotype of HEV isolated in this study. Methods:, Serum samples were collected from adult swine, cows, sheep, younger swine (< 3 months), and workers in pig farms and slaughterhouses (professional group). Fecal samples were collected from younger swine in the south suburbs of Beijing. Anti-HEV antibody was evaluated by direct sandwich enzyme immunoassay. HEV RNA was extracted from fecal samples and amplified by nested reverse transcription polymerase chain reaction (RT-nPCR). The PCR products were sequenced, and the sequence homology and phylogenetics of the HEV strains isolated from swine were analyzed. Results:, The anti-HEV positivity rates in adult swine, cows, sheep, younger swine, professional group and general population were 98.23% (222/226), 29.35% (54/184), 9.80% (20/207), 60.73% (99/164), 42.51% (105/247) and 20.29% (522/2572), respectively. The HEV RNA positivity rate of fecal samples was 22.89% (19/83) and 16/19 samples were positive for HEV RNA amplified with both primers, HEV open reading frame (ORF)1 and HEV ORF2. Sequence analysis of these 16 samples showed that there were two groups, designated BJ-1 and BJ-2. The nucleotide homology of BJ-1 and BJ-2 was 99%. Phylogenetic analysis indicated that both of these groups belonged to genotype 4d. Conclusion:, Workers in pig farms and slaughterhouses were more likely to contract HEV infection than the general population because of close contact with swine with a high prevalence of anti-HEV. [source]


A multimodal, multidimensional atlas of the C57BL/6J mouse brain

JOURNAL OF ANATOMY, Issue 2 2004
Allan MacKenzie-Graham
Abstract Strains of mice, through breeding or the disruption of normal genetic pathways, are widely used to model human diseases. Atlases are an invaluable aid in understanding the impact of such manipulations by providing a standard for comparison. We have developed a digital atlas of the adult C57BL/6J mouse brain as a comprehensive framework for storing and accessing the myriad types of information about the mouse brain. Our implementation was constructed using several different imaging techniques: magnetic resonance microscopy, blockface imaging, classical histology and immunohistochemistry. Along with raw and annotated images, it contains database management systems and a set of tools for comparing information from different techniques. The framework allows facile correlation of results from different animals, investigators or laboratories by establishing a canonical representation of the mouse brain and providing the tools for the insertion of independent data into the same space as the atlas. This tool will aid in managing the increasingly complex and voluminous amounts of information about the mammalian brain. It provides a framework that encompasses genetic information in the context of anatomical imaging and holds tremendous promise for producing new insights into the relationship between genotype and phenotype. We describe a suite of tools that enables the independent entry of other types of data, facile retrieval of information and straightforward display of images. Thus, the atlas becomes a framework for managing complex genetic and epigenetic information about the mouse brain. The atlas and associated tools may be accessed at http://www.loni.ucla.edu/MAP. [source]


Transatrial Access to the Normal Pericardial Space For Local Cardiac Therapy: Preclinical Safety Testing with Aspirin and Pulmonary Artery Hypertension

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2001
TODD C. PULERWITZ M.D.
The reliability, rapidity, and safety of nonsurgical, transatrial pericardial access for local cardiac therapy have been demonstrated in healthy animals. Since many patients take aspirin or have increased right-sided pressures, we evaluated the procedure's safety under these conditions. Transatrial pericardial access was performed in anesthetized pigs following aspirin administration (162 mg po, n = 6) or during experimental pulmonary artery hypertension (n = 4 different animals) and required only 3 minutes following guide catheter positioning. Platelet aggregability testing with arachidonic acid confirmed aspirin effectiveness. Mean pericardial fluid hematocrit was 0.1 ± 0.1% after 2 days of aspirin therapy and 1.9 ± 1.1% at sacrifice 24 hours later (NS). Mean pericardial fluid hematocrit was 1.0 ± 0.5% after 45 minutes of pulmonary artery hypertension and 4.3 ± 0.8% at sacrifice 30 minutes later (NS). Histologic analysis in both groups revealed a small thrombus and localized inflammation at the site of puncture. Neither aspirin use nor pulmonary artery hypertension causes significant bleeding into the pericardial space following transatrial access and thus does not preclude this route for local cardiac drug delivery. [source]


Regulation of Eukaryotic Initiation Factor 4E Phosphorylation in the Nervous System of Aplysia californica

JOURNAL OF NEUROCHEMISTRY, Issue 2 2000
John R Dyer
We have used an antibody that specifically recognizes eukaryotic initiation factor 4E (eIF4E) when it is phosphorylated at Ser207 to characterize eIF4E phosphorylation in the nervous system of Aplysia. The level of phosphorylated eIF4E, but not the level of total eIF4E, was significantly correlated with the basal rate of translation measured from different animals. Serotonin (5-HT), a transmitter that regulates the rate of translation in Aplysia neurons, had mixed effects on eIF4E phosphorylation. 5-HT decreased eIF4E phosphorylation in sensory cell clusters through activation of protein kinase C. 5-HT increased eIF4E phosphorylation in the whole pleural ganglia. In the Aplysia nervous system, eIF4E phosphorylation correlated with phosphorylation of the p38 MAP kinase, but not the p42 MAP kinase (ERK). Furthermore, an inhibitor of the p38 MAP kinase significantly decreased basal eIF4E phosphorylation, but an inhibitor of the MAP or ERK kinase (MEK) did not. Despite the correlation of eIF4E phosphorylation with the basal rate of translation, inhibition of eIF4E phosphorylation by an inhibitor of the p38 MAP kinase did not significantly decrease the rate of translation. [source]


POPULATION STRUCTURE IN AN INSHORE CETACEAN REVEALED BY MICROSATELLITE AND mtDNA ANALYSIS: BOTTLENOSE DOLPHINS (TURSIOPS SP.) IN SHARK BAY, WESTERN AUSTRALIA

MARINE MAMMAL SCIENCE, Issue 1 2004
Michael Krützen
Abstract We examined population substructure of bottlenose dolphins (Tursiops sp). in Shark Bay, Western Australia, using 10 highly polymorphic microsatellite loci, and mitochondrial DNA (mtDNA). For microsatellite analysis, 302 different animals were sampled from seven localities throughout the bay. Analysis of genetic differentiation between sampling localities showed a significant correlation between the number of migrants (Nm) calculated from FST, RST and private alleles, and distance between localities,a pattern of isolation-by-distance. For mtDNA, 220 individuals from all seven localities were sequenced for a 351 base pair fragment of the control region, resulting in eight haplotypes, with two distinct clusters of haplotypes. Values of FST and (,)ST for mtDNA yielded statistically significant differences, mostly between localities that were not adjacent to each other, suggesting female gene flow over a scale larger than the sampled localities. We also observed a significant correlation between the number of female migrants calculated from FST and ,ST and the distance of sampling localities. Our results indicate that dispersal in female dolphins in Shark Bay is more restricted than that of males. [source]


Tiling among stereotyped dendritic branches in an identified Drosophila motoneuron

THE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 12 2010
F. Vonhoff
Shape similarities of an identified Drosophila motoneuron across animals. Overlay of three geometric dendrite reconstructions of a Drosophila flight motoneuron, based on intracellular fills of this motoneuron in different animals with identical genotypes. Although similarities exist in the overall branching structure, and the dendritic territories are nearly identical in all three cells, marked differences exist in the fine branching structure. The Journal of Comparative Neurology, Volume 518, Number 12, pages 2169,2185. [source]


Bacterial diversity in various coastal mariculture ponds in Southeast China and in diseased eels as revealed by culture and culture-independent molecular techniques

AQUACULTURE RESEARCH, Issue 9 2010
Yonghui Zeng
Abstract Mariculture ponds are widely distributed in Chinese coasts and have become a threat to the health of coastal ecosystems. In order to improve our understanding on the microbial composition in mariculture environments, we sampled a variety of ponds farming different animals or plants around the Dongshan Island and Xiamen Island in Southeast China and isolated cultures from the tissues of diseased eels. Analysis by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE), clone library and direct culturing methods revealed highly diverse bacterial communities in these samples. Bacterial communities in the Dongshan samples were dominated by Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. The Gracilaria verrucosa pond harbours the most abundant species (20 DGGE bands), followed by Epinephelus diacanthus pond (18 bands), Haliotis diversicolor supertexta pond I (18 bands) and Penaeus vannamei pond (11 bands). In comparison with surface waters, Penacus orientalis pond sediment showed a much more complex bacterial community, from which only sequences affiliated with Deltaproteobacteria, Firmicutes, Acidobacteria and candidate phylum TM6 were found. Bacterial cultures in diseased eels were closely related to two pathogenic genera, Aeromonas in Gammaproteobacteria and Bacillus, in Firmicutes. Clones affiliated with another two genera, Escherichia and Vibrio, that have pathogenic potentials were also identified. Phylogenetic analysis of a total of 131 sequences showed that 48.9% of the sequences were clustered into Gammaproteobacteria and formed the most abundant group, followed by Alphaproteobacteria (19.1%), Firmicutes (7.6%), Bacteroidetes (5.3%), Deltaproteobacteria (5.3%), Actinobacteria (4.6%), Chloroplast (3.8%), Acidobacteria (2.3%), Cyanobacteria (1.5%), Betaproteobacteria (0.7%) and TM6 (0.7%). 43.7% (28/64) of the phylogenetic clusters cannot be classified into any known genus and 44.3% (58/131) of the sequences show <95% similarity to public database records, suggesting that abundant novel species exist in mariculture ponds. Gathering bacterial diversity data in mariculture ponds and diseased fish is meaningful for the prevention and control of fish diseases and for the improvement of our understanding of microbial ecology in a pond environment. [source]


Using Mixtures to Model Heterogeneity in Ecological Capture-Recapture Studies

BIOMETRICAL JOURNAL, Issue 6 2008
Shirley Pledger
Abstract Modelling heterogeneity of capture is an important problem in estimating animal abundance from capturerecapture data, with underestimation of abundance occurring if different animals have intrinsically high or low capture probabilities. Mixture models are useful in many cases to model the heterogeneity. We summarise mixture model results for closed populations, using a skink data set for illustration. New mixture models for heterogeneous open populations are discussed, and a closed population model is shown to have new and potentially effective applications in community analysis. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Diverse optical characteristic of the prostate and light delivery system: implications for computer modelling of prostatic photodynamic therapy

BJU INTERNATIONAL, Issue 9 2005
Jerzy Jankun
OBJECTIVE To explore the use of photodynamic therapy (PDT) as a minimally invasive form of treatment for organ-confined prostate cancer, for although there are several therapies, ablative treatments are associated with significant morbidity. MATERIALS AND METHODS Using the photosensitizer tin etiopurpurin, dogs were treated with interstitially placed laser fibres in an effort to validate PDT for treating prostate cancer. Earlier models assumed a uniform distribution of light output from a cylindrical fibre and a uniform attenuation coefficient throughout the prostate. Subsequent observations show that this model was too simple and that light radiance is not linear. To overcome under-treatment, a computer program to complement real-time fibre placement was developed. RESULTS As light radiance from interstitially placed laser fibres varies significantly from the commonly assumed ideal cylindrical emission, a predictive mathematical model of prostate PDT needs to consider the real emission. Also, the optical properties of the prostate, e.g. absorption and scattering of light, are anisotropic. Differences in the attenuation coefficient (combining absorption and scattering of light) also varied among different animals. Incorporating all these variables into a computer program produced a virtual model of the photo-ablated zone within ± 2 mm of that observed in animals. CONCLUSION PDT of the prostate is not trivial and should benefit from computer-aided methods as it is developed for clinical use. [source]


Bone formation at titanium porous oxide (TiUniteÔ) oral implants in type IV bone

CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2005
Yi-Hao Huang
Abstract Background: Several oral implant design advances have been suggested to overcome poor bone quality, an impediment for successful implant treatment. A novel titanium porous oxide (TPO) surface has been shown to offer favorable results in several settings. The objective of this study was to evaluate the local bone formation and osseointegration at TPO-modified implants in type IV bone. Method: Three TPO surface-modified implants (TiUniteÔ) were installed into the edentulated posterior maxilla in each of 8 Cynomolgus monkeys. The animals were injected with fluorescent bone labels at 2, 3, 4 and 16 weeks post-surgery and were euthanized at week 16 when block biopsies were collected for histologic analysis. Results: The predominant observation of the TPO implant surface was a thin layer of new bone covering most of the implant threads. Mean (±SE) bone,implant contact for the whole study group was 74.1±4.8%. There was a significant variability in bone,implant contact between animals (P=0.0003) and between sites of the same animal (P<0.0001). The variance in bone,implant contact was 30% larger among sites of the same animal than between different animals (187.5 vs. 144.8, respectively). There was a small but significant difference in bone density immediately outside, compared to within the threaded area of the implants (37.1±3.2% vs. 32.1±3.2%, P<0.0001). Bone density outside the implant threads was significantly correlated (,=0.682, P<0.0001) with the bone density within thethreaded area. Bone density within the threaded area was significantly correlated (,=0.493, P=0.0002) with bone,implant contact, whereas bone density outside the implant threads did not have a significant effect (,=0.232, P=0.1). Conclusions: The results suggest that the TPO surface possesses a considerable osteoconductive potential promoting a high level of implant osseointegration in type IV bone in the posterior maxilla. Résumé Différents nouveaux modèles d'implants ont été suggéréspour tenter de compenser la mauvaise qualité osseuse qui est un problème pour le traitement implantaire à succès. Une nouvelle surface en oxyde poreux de titane (TPO) a apporté des résultats favorables en différentes occasions. L'objectif de cette étude a été d'évaluer la formation osseuse locale et l'ostéoïntégration d'implants modifiés TPO dans de l'os de qualité type IV. Trois implants dont la surface était modifiée TPO (TiUniteTM) ont été insérés dans un maxillaire édenté postérieur de huit singes cynomolgus. Les animaux ont subi des injections de marqueurs osseux par flurorescence à deux, trois, quatre et seize semaines après la chirurgie et ont été euthanasiés à la semaine 16 quand des biopsies en bloc ont été prélevées pour l'analyse histologique. L'observation prédominante de la surface implantaire TPO était une fine couche de nouvel os couvrant la plupart des filetages implantaires. La moyenne ±SE du contact os-implant pour tout le groupe étudiéétait de 74±5%. Il y avait une variation significative dans le contact os-implant entre les animaux (P<0,0003) et entre les sites d'un même animal (P<0,0001). La variance du contact os-implant était 30% plus importante parmi les sites du même animal qu'entre différents animaux (respectivement 187 et 145). Il y avait une différence significative bien que faible dans la densité osseuse immédiatement á l'extérieur comparéà l'intérieur des zones à filetage des implants (37±3% vs 32±3%, P<0,0001). La densité osseuse en dehors des filetages implantaires était en corrélation significative (ß=0,682, P<0,0001) avec la densité osseuse à l'intérieur des zones de filetage. La densité osseuse à l'intérieur des zones de filetage était en corrélation significative (ß=0,493, P<0,0002) avec le contact os-implant, tandis que la densité osseuse en dehors des filetages implantaires n'avait pas d'effet significatif (ß=0,232, P=0,1). Ces résultats suggèrent que la surface TPO possède un potentiel ostéoconducteur considérable qui peut promouvoir une ostéoïntégration implantaire de haut niveau dans l'os de type IV dans la région maxillaire postérieure. Zusammenfassung Ziel: Um trotz schlechter Knochenqualität die Aussicht auf eine erfolgreiche implantologische Behandlung zu verbessern, wurden verschiedene Entwicklungen des Designs von Zahnimplantaten vorgeschlagen. Bei verschiedenen Gelegenheiten hat eine neue poröse Titanoxidoberfläche (TPO) scheinbar vorteilhafte Resultate gezeigt. Das Ziel dieser Studie war, die lokale Knochenbildung und die Osseointegration von Implantaten mit einer TPO-modifizierten Oberfläche im Typ IV Knochen zu untersuchen. Methode: In die zahnlosen posterioren Oberkiefern eines jeden von 8 Cynomolgus-Affen implantierte man drei Implantate mit einer TPO-modifizierten Oberfläche (TiUnite®). Den Tieren wurden 2, 3, 4 und 16 Wochen nach dem chirurgischen Eingriff fluoreszierende Knochenmarker injiziert und in der Wochen 16 wurden sie eingeschläfert und für die histologische Analyse Blockbiopsien entnommen. Resultate: Die wichtigste Beobachtung bei der TPO-Implantatoberfläche war eine dünne Schicht neuen Knochens, welche die meisten Schraubenwindungen des Implantates bedeckte. Der mittlere Knochen-Implantatkontakt (±SE) betrug in der ganzen Testgruppe 74.1±4.8%. Man fand eine signifikante Variabilität des Knochen-Implantatkontaktes unterhalb der Tiere (P=0.0003) und auch unterhalb der verschiedenen Impantate desselben Tieres (P<0.0001). Innerhalb der Implantate desselben Tieres war die Varianz des Knochen-Implantatkontaktes bis zu 30% grösser, als zwischen den verschiedenen Tieren (187.5 gegenüber 144.8). Man fand auch einen kleinen, aber signifikanten Unterschied der Knochendichte im Bereich direkt ausserhalb der Schraubenwindungen, verglichen mit dem inneren Bereich (37.1±3.2% gegenüber 32.1±3.2%, P<0.0001). Diese beiden Knochendichten waren aber signifikant miteinander korreliert (0.682, P<0.0001). Die Knochendichte innerhalb der Schraubenwindungen korrelierte signifikant mit dem Knochen-Implantat-Kontakt (ß=0.493, P=0.0002), währenddem die Knochendichte ausserhalb des Bereiches der Schraubenwindungen in dieser Beziehung keine signifikante Korrelation aufwies (ß=0.232, P=0.1). Zusammenfassung: Die Resultate lassen vermuten, dass die TPO-Oberfläche eine beachtliche osteokonduktive Fähigkeit hat, die im posterioren Oberkieferbereich mit Typ IV Knochen zu einer sehr guten Osseointegration führt. Resumen Antecedentes: Se han sugerido varios avances en los diseños de los implantes orales para superar una baja calidad de hueso, un impedimento para un tratamiento exitoso de implantes. Se ha presentado una nueva superficie de óxido de titanio poroso (TPO) que ofrece resultados favorables en diversas situaciones. El objetivo de este estudio fue evaluar la formación local de hueso y la osteointegración en implantes TPO modificados en hueso tipo IV. Método: Se instalaron tres implantes (TiUniteTM) con superficie modificada TPO en el maxilar posterior edéntulo en 8 monos Cynomolgus. Los animales fueron inyectados con marcadores óseos fluorescentes en la semana 2, 3, 4 y 16 tras la cirugía y se sacrificaron en la semana 16 recogiéndose biopsias en bloque para análisis histológicos. Resultados: La observación predominante de la superficie TPO del implante fue una fina capa de hueso nuevo cubriendo la mayor parte de las roscas. El contacto hueso-implante medio (±SE) para todo el grupo de estudio fue de 74.1±4.8%. Hubo una variabilidad significativa en el contacto hueso-implante entre animales (P=0.0003) y entre lugares del mismo animal (P<0.0001). La varianza en el contacto hueso-implante fue un 30% mayor entre lugares del mismo animal que entre los diferentes animales (187.5 vs. 144.8, respectivamente). Hubo una pequeña pero significativa diferencia en la densidad ósea inmediatamente por fuera comparada con el área roscada de los implantes (37.1±3.2% vs. 32.1±3.2%, P<0.0001). La densidad ósea por fuera de las roscas del implante se correlacionó significativamente (,=0.682, P<0.0001) con la densidad ósea entre las áreas de roscas. La densidad ósea entre las áreas de roscas se correlacionó significativamente (,=0.492, P<0.0002) con el contacto hueso implante, mientras que la densidad ósea por fuera de las roscas del implante no tuvo un efecto significativo (,=0.232, P=0.1). Conclusiones: Los resultados sugieren que la superficieTPOposee un considerable potencial osteoconductivo promoviendo un alto nivel de osteointegracióndel implante en hueso tipo IV en el maxilar posterior. [source]