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1.
Using the non-destructive technique of 3-D micro computed tomography (3-D-μCT), we present a new, virtual reconstruction of the Le Moustier 1 Neandertal skull. This new reconstruction corrects defects found in earlier reconstruction attempts by repositioning misaligned cranial fragments, addressing the problem of asymmetry caused by pressure during the fossilization process, and placing the basioccipital in its proper anatomical position. Metric comparisons between Le Moustier 1 and juvenile and adult Neandertals demonstrate that facial height proceeded at a faster rate of growth than facial prognathism at the beginning of the adolescent period. They also confirm the anterior placement of the basioccipital. A compound painted to match the colour of the fossilized bone was used in previous reconstruction attempts and the aim of this analysis was to remove the false material to reveal to what extent the fossilized bone was preserved. The areas with the most artificial material and glue include the palate, areas around the mandibular teeth, the left frontal, and parts of the right parietal and temporal bones. The μCT data were also used to examine internal structures of the skull including the frontal sinus and the labyrinth of the inner ear. An investigation of the frontal sinus reveals morphology similar to that found in adult Neandertals, although the structure does not extend to mid-orbit. The dimension of the radius of curvature of the lateral semicircular canal falls within one standard deviation, and the anterior and posterior canals within two standard deviations, of the published Neandertal mean. As in other Neandertals, the posterior semicircular canal is in an inferior position relative to the plane of the lateral canal.  相似文献   

2.
Currently in physical anthropology there is a need for reliable methods of sex estimation for immature individuals and highly fragmented remains. This study develops a sex estimation technique from discriminant function analysis of the bony labyrinth as it matures before puberty and can survive taphonomic conditions that would destroy most other skeletal material. The bony labyrinth contains the organs of hearing and balance. For this reason biologists and paleoanthropologists have undertaken research in this area to understand evolutionary changes in locomotion. Prior studies have found clear differences between species, but within‐species variation has not been satisfactorily investigated. 3D segmentations of the left and right labyrinths of 94 individuals from a Cretan collection were generated and measured. Mean measurements of height, width, size, and shape indices were analyzed for sexual dimorphism, bilateral asymmetry, and measurement error. Significant sexual dimorphism was detected for several measurements. For sex estimation, the single best variable was the radius of curvature of the posterior semicircular canal, which achieved 76% accuracy. Two multivariate functions increased accuracy to 84%. Although these equations are less accurate than equations for complete long bones and crania, they appear to be as accurate as or better than other techniques for sexing immature individuals and temporal bones. Am J Phys Anthropol 151:290–301, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

3.
Odontophoral cartilages are located in the molluscan buccal mass and support the movement of the radula during feeding. The structural diversity of odontophoral cartilages is currently known only from limited taxa, but this information is important for interpreting phylogeny and for understanding the biomechanical operation of the buccal mass. Caenogastropods exhibit a wide variety of feeding strategies, but there is little comparative information on cartilage morphology within this group. The morphology of caenogastropod odontophoral cartilages is currently known only from dissection and histology, although preliminary results suggest that they may be structurally diverse. A comparative morphological survey of 18 caenogastropods and three noncaenogastropods has been conducted, sampling most major caenogastropod superfamilies. Three‐dimensional models of the odontophoral cartilages were generated using X‐ray microscopy (micro‐CT) and reconstruction by image segmentation. Considerable morphological diversity of the odontophoral cartilages was found within Caenogastropoda, including the presence of thin cartilaginous appendages, asymmetrically overlapping cartilages, and reflexed cartilage margins. Many basal caenogastropod taxa possess previously unidentified cartilaginous support structures below the radula (subradular cartilages), which may be homologous to the dorsal cartilages of other gastropods. As subradular cartilages were absent in carnivorous caenogastropods, adaptation to trophic specialization is likely. However, incongruence with specific feeding strategies or body size suggests that the morphology of odontophoral cartilages is constrained by phylogeny, representing a new source of morphological characters to improve the phylogenetic resolution of this group. J. Morphol. 2009. © 2008 Wiley‐Liss, Inc.  相似文献   

4.
Previous research has demonstrated that species and subspecies of extant chimpanzees and bonobos can be distinguished on the basis of the shape of their molar crowns. Thus, there is potential for fossil taxa, particularly fossil hominins, to be distinguished at similar taxonomic levels using molar crown morphology. Unfortunately, due to occlusal attrition, the original crown morphology is often absent in fossil teeth, and this has limited the amount of shape information used to discriminate hominin molars. The enamel–dentine junction (EDJ) of molar teeth preserves considerable shape information, particularly in regard to the original shape of the crown, and remains present through the early stages of attrition. In this study, we investigate whether the shape of the EDJ of lower first and second molars can distinguish species and subspecies of extant Pan. Micro‐computed tomography was employed to non‐destructively image the EDJ, and geometric morphometric analytical methods were used to compare EDJ shape among samples of Pan paniscus (N = 17), Pan troglodytes troglodytes (N = 13), and Pan troglodytes verus (N = 18). Discriminant analysis indicates that EDJ morphology distinguishes among extant Pan species and subspecies with a high degree of reliability. The morphological differences in EDJ shape among the taxa are subtle and relate to the relative height and position of the dentine horns, the height of the dentine crown, and the shape of the crown base, but their existence supports the inclusion of EDJ shape (particularly those aspects of shape in the vertical dimension) in the systematic analysis of fossil hominin lower molars. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

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6.
Osteogenesis imperfecta (OI) is commonly caused by heterozygous type I collagen structural mutations that disturb triple helix folding and integrity. This mutant‐containing misfolded collagen accumulates in the endoplasmic reticulum (ER) and induces a form of ER stress associated with negative effects on osteoblast differentiation and maturation. Therapeutic induction of autophagy to degrade the mutant collagens could therefore be useful in ameliorating the ER stress and deleterious downstream consequences. To test this, we treated a mouse model of mild to moderate OI (α2(I) G610C) with dietary rapamycin from 3 to 8 weeks of age and effects on bone mass and mechanical properties were determined. OI bone mass and mechanics were, as previously reported, compromised compared to WT. While rapamycin treatment improved the trabecular parameters of WT and OI bones, the biomechanical deficits of OI bones were not rescued. Importantly, we show that rapamycin treatment suppressed the longitudinal and transverse growth of OI, but not WT, long bones. Our work demonstrates that dietary rapamycin offers no clinical benefit in this OI model and furthermore, the impact of rapamycin on OI bone growth could exacerbate the clinical consequences during periods of active bone growth in patients with OI caused by collagen misfolding mutations.  相似文献   

7.
Imaging techniques are a cornerstone of contemporary biology. Over the last decades, advances in microscale imaging techniques have allowed fascinating new insights into cell and tissue morphology and internal anatomy of organisms across kingdoms. However, most studies so far provided snapshots of given reference taxa, describing organs and tissues under “idealized” conditions. Surprisingly, there is an almost complete lack of studies investigating how an organism′s internal morphology changes in response to environmental drivers. Consequently, ecology as a scientific discipline has so far almost neglected the possibilities arising from modern microscale imaging techniques. Here, we provide an overview of recent developments of X‐ray computed tomography as an affordable, simple method of high spatial resolution, allowing insights into three‐dimensional anatomy both in vivo and ex vivo. We review ecological studies using this technique to investigate the three‐dimensional internal structure of organisms. In addition, we provide practical comparisons between different preparation techniques for maximum contrast and tissue differentiation. In particular, we consider the novel modality of phase contrast by self‐interference of the X‐ray wave behind an object (i.e., phase contrast by free space propagation). Using the cricket Acheta domesticus (L.) as model organism, we found that the combination of FAE fixative and iodine staining provided the best results across different tissues. The drying technique also affected contrast and prevented artifacts in specific cases. Overall, we found that for the interests of ecological studies, X‐ray computed tomography is useful when the tissue or structure of interest has sufficient contrast that allows for an automatic or semiautomatic segmentation. In particular, we show that reconstruction schemes which exploit phase contrast can yield enhanced image quality. Combined with suitable specimen preparation and automated analysis, X‐ray CT can therefore become a promising quantitative 3D imaging technique to study organisms′ responses to environmental drivers, in both ecology and evolution.  相似文献   

8.
In developing CNS D1 dopamine receptor-imaging agents with improved specificity and longer brain retention, an iodinated D1 ligand was synthesized. In vitro and in vivo radiolabeling studies of a new iodinated benzazepine, TISCH [7-chloro-8-hydroxy-1-(3'-iodophenyl)-3-methyl-2,3,4,5-tetrahydro-1H-3- benzazepine], an analog of SCH 23390 (7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepin e), were investigated. After an intravenous injection, the R(+) isomer of TISCH showed high brain uptake in rats (2.20 and 0.57% dose per whole brain at 2 and 60 min, respectively). The striatum/cerebellum ratio increased progressively with time (12 at 60 min). Ex vivo autoradiography of rat brain sections, after intravenous injection of R(+)-[125I]TISCH, displayed the highest uptake in striatum and substantia nigra, regions known to have a high concentration of D1 receptors, whereas the S(-) isomer displayed no specific uptake. Furthermore, the specific uptake can be blocked by pretreatment with SCH 23390. In vitro binding studies using the rat striatum tissue preparation showed high specific and low nonspecific bindings (KD = 0.21 +/- 0.03 nM). The rank order of potency exhibiting high specificity to the D1 receptor was SCH 23390 greater than (+/-)-TISCH greater than (+)-butaclamol = (+/-)-FISCH [7-chloro-8-hydroxy-1-(4'-iodophenyl)-3-methyl-2,3,4,5-tetrahydro-1 H-3-benzazepine] much greater than WB4101 = spiperone greater than dopamine, serotonin, (+/-)-propranolol, and naloxone. Imaging studies in a monkey with the resolved isomer, R(+)-[123I]TISCH, demonstrated a high uptake in the basal ganglia and prolonged retention. The preliminary data suggest that R(+)-TISCH is selective for the CNS D1 receptor and is potentially useful for in vivo and in vitro pharmacological studies. When labeled with iodine-123, it may be suitable for noninvasive imaging in humans.  相似文献   

9.
10.
In clinical routine, lower limb analysis relies on conventional X-ray (2D view) or computerised tomography (CT) Scan (lying position). However, these methods do not allow 3D analysis in standing position. The aim of this study is to propose a fast and accurate 3D-reconstruction-method based on parametric models and statistical inferences from biplanar X-rays with clinical measurements' (CM) assessment in standing position for a clinical routine use. For the reproducibility study, the 95% CI was under 2.7° for all lower limbs' angular measurements except for tibial torsion, femoral torsion and tibiofemoral rotation ( < 5°). The 95% CI were under 2.5 mm for lower limbs' lengths and 1.5 to 3° for the pelvis' CM. Comparisons between X-rays and CT-scan based 3D shapes in vitro showed mean differences of 1.0 mm (95% CI = 2.4 mm). Comparisons of 2D lower limbs' and 3D pelvis' CM between standing ‘Shifted-Feet’ and ‘Non-Shifted-Feet’ position showed means differences of 0.0 to 1.4°. Significant differences were found only for pelvic obliquity and rotation. The reconstruction time was about 5 min.  相似文献   

11.
The present work provides the first information concerning the chemoattractant activity of trout recombinant IL-1β and its derived peptides, referred to as P1, P2 and P3. The predicted rainbow trout mature interleukin-1β peptide was produced as a recombinant protein in Escherichia coli. The first peptide, P1, corresponded to fragment 146–157 (YVTPVPIETEAR) of the trout sequence and had an MW of 1·37 kDa. It was equivalent to a region known to be part of the receptor binding domain from the mammalian crystal structure of IL-1β complexed to its receptor. P2 was used as control peptide, consisting of the same 12 amino acids as P1, but arranged in a random sequence (VVEEYIRAPPTT). P3 was synthesised to complex with an adjacent region of the IL-1 receptor, and corresponded to fragment 207–216 (YRRNTGVDIS) of the trout sequence, with an MW of 1·18 kDa. Migration was stimulated when leucocytes were exposed to concentrations of ≥10 ng ml−1rIL-1β. Peptide P3 also induced leucocyte migration, with an optimal dose of 0·25 mm being recorded. While P1 had no effect on cell migration when used alone, synergism was evident as a consequence of combining P1 with a suboptimal dose (0·01 mm) of P3. No synergism occurred when cells were exposed to a combination of P3 and the control peptide P2.  相似文献   

12.
D2/D3 dopamine receptors (D2R/D3R) agonists regulate Akt, but their effects display a complex time‐course. In addition, the respective roles of D2R and D3R are not defined and downstream targets remain poorly characterized, especially in vivo. These issues were addressed here for D3R. Systemic administration of quinelorane, a D2R/D3R agonist, transiently increased phosphorylation of Akt and GSK‐3β in rat nucleus accumbens and dorsal striatum with maximal effects 10 min after injection. Akt activation was associated with phosphorylation of several effectors of the mammalian target of rapamycin complex 1 (mTORC1): p70S6 kinase, ribosomal protein‐S6 (Ser240/244), and eukaryotic initiation factor‐4E binding protein‐1. The action of quinelorane was antagonized by a D2/D3R antagonist, raclopride, and the selective D3R antagonist S33084, inactive by themselves. Furthermore, no effect of quinerolane was seen in knock‐out mice lacking D3R. In drd1a‐EGFP transgenic mice, quinelorane activated Akt/GSK‐3β in both neurons expressing and lacking D1 receptor. Thus, the stimulation of D3R transiently activates the Akt/GSK‐3β pathway in the two populations of medium‐size spiny neurons of the nucleus accumbens and dorsal striatum. This effect may contribute to the influence of D3R ligands on reward, cognition, and processes disrupted in schizophrenia, drug abuse, and Parkinson's disease.  相似文献   

13.
Males can increase their reproductive success by mechanically hindering females to mate with subsequent males. Research on mating plugs so far has focused on the fitness consequences and demonstrated that plug size can strongly determine its efficacy. Here, we explore: (1) the site of plug production in the erigonine spider Oedothorax retusus; and (2) whether males are limited in the production of plug material when mating with three females in succession. Micro‐computed tomography, histological and ultrastructural sections demonstrate that the plug material is produced in a massive gland inside the sperm transfer organs of the male, the pedipalps. The glandular lumen is connected with the tube‐like spermophore almost at its blind end. Probably, a reservoir of plug material is built up at the end of the spermophore and released after sperm transfer onto the female genital opening. Since not all males applied a large plug during their first mating, there was no significant decline in plug size over the course of the three successive matings. However, the size of the first plug significantly affected the size of the following plug. We discuss these findings in the light of plug limitation and mate choice. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 345–354.  相似文献   

14.
Leukocyte immunoglobulin-like receptors (LILRs), also called CD85s, ILTs, or LIRs, are important mediators of immune activation and tolerance that contain tandem immunoglobulin (Ig)-like folds. There are 11 (in addition to two pseudogenes) LILRs in total, two with two Ig-like domains (D1D2) and the remaining nine with four Ig-like domains (D1D2D3D4). Thus far, the structural features of the D1D2 domains of LILR proteins are well defi ned, but no structures for the D3D4 domains have been reported. This is a very important fi eld to be studied as it relates to the unknown functions of the D3D4 domains, as well as their relative orientation to the D1D2 domains on the cell surface. Here, we report the crystal structures of the D3D4 domains of both LILRB1 and LILRB2. The two Iglike domains of both LILRB1-D3D4 and LILRB2-D3D4 are arranged at an acute angle (~60°) to form a bent structure, resembling the structures of natural killer inhibitory receptors. Based on these two D3D4 domain structures and previously reported D1D2/HLA I complex structures, two alternative models of full-length (four Ig-like domains) LILR molecules bound to HLA I are proposed.  相似文献   

15.
16.
It is well established that cancer cells depend upon aerobic glycolysis to provide the energy they need to survive and proliferate. However, anti‐glycolytic agents have yielded few positive results in human patients, in part due to dose‐limiting side effects. Here, we discovered the unexpected anti‐cancer efficacy of Polydatin (PD) combined with 2‐deoxy‐D‐glucose (2‐DG), which is a compound that inhibits glycolysis. We demonstrated in two breast cell lines (MCF‐7 and 4T1) that combination treatment with PD and 2‐DG induced cell apoptosis and inhibited cell proliferation, migration and invasion. Furthermore, we determined the mechanism of PD in synergy with 2‐DG, which decreased the intracellular reactive oxygen (ROS) levels and suppressed the PI3K/AKT pathway. In addition, the combined treatment inhibited the glycolytic phenotype through reducing the expression of HK2. HK2 deletion in breast cancer cells thus improved the anti‐cancer activity of 2‐DG. The combination treatment also resulted in significant tumour regression in the absence of significant morphologic changes in the heart, liver or kidney in vivo. In summary, our study demonstrates that PD synergised with 2‐DG to enhance its anti‐cancer efficacy by inhibiting the ROS/PI3K/AKT/HIF‐1α/HK2 signalling axis, providing a potential anti‐cancer strategy.  相似文献   

17.
Inflammation plays a major role in progression of rheumatoid arthritis, a disease treated with antagonists of tumor necrosis factor‐alpha (TNF‐α) and interleukin 1β (IL‐1β). New in vitro testing systems are needed to evaluate efficacies of new anti‐inflammatory biological drugs, ideally in a patient‐specific manner. To address this need, we studied microspheroids containing 10,000 human osteoarthritic primary chondrocytes (OACs) or chondrogenically differentiated mesenchymal stem cells (MSCs), obtained from three donors. Hypothesizing that this system can recapitulate clinically observed effects of anti‐inflammatory drugs, spheroids were exposed to TNF‐α, IL‐1β, or to supernatant containing secretome from activated macrophages (MCM). The anti‐inflammatory efficacies of anti‐TNF‐α biologicals adalimumab, infliximab, and etanercept, and the anti‐IL‐1β agent anakinra were assessed in short‐term microspheroid and long‐term macrospheroid cultures (100,000 OACs). While gene and protein expressions were evaluated in microspheroids, diameters, amounts of DNA, glycosaminoglycans, and hydroxiproline were measured in macrospheroids. The tested drugs significantly decreased the inflammation induced by TNF‐α or IL‐1β. The differences in potency of anti‐TNF‐α biologicals at 24 h and 3 weeks after their addition to inflamed spheroids were comparable, showing high predictability of short‐term cultures. Moreover, the data obtained with microspheroids grown from OACs and chondrogenically differentiated MSCs were comparable, suggesting that MSCs could be used for this type of in vitro testing. We propose that in vitro gene expression measured after the first 24 h in cultures of chondrogenically differentiated MSCs can be used to determine the functionality of anti‐TNF‐α drugs in personalized and preclinical studies. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1045–1058, 2018  相似文献   

18.
19.
Cozza G  Moro S  Gotte G 《Biopolymers》2008,89(1):26-39
By lyophilization from 40% acetic acid solutions, bovine pancreatic ribonuclease A forms several three-dimensional (3D) domain-swapped oligomers: dimers, trimers, tetramers, pentamers, hexamers, and traces of high-order oligomers, purifiable by cation-exchange chromatography. Each oligomeric species consists of at least two conformers displaying different basicity density, and/or exposure of positive charges. The structures of the two dimers and one trimer have been solved. Plausible models have been proposed for a second RNase A trimer and four tetramers, but not all the models are certainly assignable to the tetramers purified. Further studies have also been made on the pentameric and hexameric species, again without reaching structurally clear-cut results. This work is focused on the detailed modeling of the tetrameric RNase A species, using four different approaches to possibly clarify unknown structural aspects. The results obtained do not confirm the validity of one tetrameric model previously proposed, but allow the proposal of a novel tetrameric structure displaying new interfaces that are absent in the other known conformers. New details concerning other tetrameric structures are also described. RNase A multimers larger than tetramers, i.e., pentamers, hexamers, octamers, nonamers, up to dodecamers, are also modeled, with the proposal of novel domain-swapped structures, and the confirmation of what had previously been inferred. Finally, the propensity of RNase A to possibly form high-order supramolecular multimers is analyzed starting from the large number of domain-swapped RNase A conformers modeled.  相似文献   

20.
Rotator cuff (RC) tears may be associated with increased glenohumeral instability; however, this instability is difficult to quantify using currently available diagnostic tools. Recently, the three-dimensional (3D) reconstruction and registration method of the scapula and humeral head, based on sequences of low-dose biplane X-ray images, has been proposed for glenohumeral displacement assessment. This research aimed to evaluate the accuracy and reproducibility of this technique and to investigate its potential with a preliminary application comparing RC tear patients and asymptomatic volunteers. Accuracy was assessed using CT scan model registration on biplane X-ray images for five cadaveric shoulder specimens and showed differences ranging from 0.6 to 1.4 mm depending on the direction of interest. Intra- and interobserver reproducibility was assessed through two operators who repeated the reconstruction of five subjects three times, allowing defining 95% confidence interval ranging from ±1.8 to ±3.6 mm. Intraclass correlation coefficient varied between 0.84 and 0.98. Comparison between RC tear patients and asymptomatic volunteers showed differences of glenohumeral displacements, especially in the superoinferior direction when shoulder was abducted at 20° and 45°. This study thus assessed the accuracy of the low-dose 3D biplane X-ray reconstruction technique for glenohumeral displacement assessment and showed potential in biomechanical and clinical research.  相似文献   

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