FGF-10 Stimulates Limb Regeneration Ability in Xenopus laevis

AbstractBy reciprocal transplantation experiments with regenerative and nonregenerative Xenopus limbs, we recently demonstrated that the regenerative capacity of a Xenopus limb depends on mesenchymal tissue and we suggested that fgf-10 is likely to be involved in this capacity (Yokoyama et al., 2000, Dev. Biol. 219, 18–29). However, the data obtained in that study are not conclusive evidence that FGF-10 is responsible for the regenerative capacity. We therefore investigated the role of FGF-10 in regenerative capacity by directly introducing FGF-10 protein into nonregenerative Xenopus limb stumps. Exogenously applied FGF-10 successfully stimulated the regenerative capacity, resulting in the reinduction of all gene expressions (including shh, msx-1, and fgf-10) that we examined and the regeneration of well-patterned limb structures. We report here for the first time that a certain molecule activates the regenerative capacity of Xenopus limb, and this finding suggests that FGF-10 could be a key molecule in possible regeneration of nonregenerative limbs in higher vertebrates

マトリックスメタロプロテアーゼと膵疾患

Matrix metalloproteinases (MMPs) is a family of collagenolytic enzymesand are associated with many pathological conditions. Especially, MMPs have a strong relation with tumor progression and invasion. In this review, we focused on association of MMPs and pancreatic diseases, and a potential treatment of MMPs inhibitors for pancreatic cancer.マトリックスメタロブロテアーゼ（MMP）は，コラーゲン分解能を有し，種々の疾患との関連性が示唆されている。とりわけ,癌の浸潤，転移には密接な関係があるとされている。また，MMP阻害剤を癌の治療に用いる試みもなされている。本稿ではMMPと膵疾患の関連性，MMP阻害剤の膵癌への応用の可能性について総説する

Multiple Digit Formation inXenopusLimb Bud Recombinants

AbstractWe prepared recombinant limb buds ofXenopustadpoles by grafting a mesenchyme mass of the hindlimb bud. TheXenopusrecombinant limb buds with dissociated and reaggregated mesenchyme developed more than 30 digits with cartilage segmentation, while those with undissociated mesenchyme developed a limb with normal cartilage pattern. Before the formation of multiple digits, a patchy expression pattern offgf-8,an AER marker, was observed in the distal region of recombinant limb buds.shh,a ZPA (zone of polarizing activity) marker, was expressed broadly in the distal region of recombinants. Recombinant limb buds with the reaggregated mesenchyme of anterior halves formed anterior digits with claws, and those with the mesenchyme of posterior halves formed posterior digits without claws. The temporal and spatial changes in the potency of multiple digit formation are discussed with reference to the regenerative capacity ofXenopuslimb buds

Suppression of cell cycle progression by Jun dimerization protein (JDP2) involves down-regulation of cyclin A2

We report here a novel role for Jun dimerization protein-2 (JDP2) as a regulator of the progression of normal cells through the cell cycle. To determine the role of JDP2 in vivo, we generated Jdp2 knock-out (Jdp2KO) mice by targeting exon 1 to disrupt the site of initiation of transcription. The healing of wounded skin of Jdp2KO mice proceeded more rapidly than that of control mice and more proliferating cells were found at wound margins. Fibroblasts derived from embryos of Jdp2KO mice proliferated more rapidly and formed more colonies than wild-type fibroblasts. JDP2 was recruited to the promoter of the gene for cyclin A2 (ccna2) at a previously unidentified AP-1 site. Cells lacking Jdp2 had elevated levels of cyclin A2 mRNA. Moreover, reintroduction of JDP2 resulted in repression of transcription of ccna2 and of cell cycle progression. Thus, transcription of the gene for cyclin A2 appears to be a direct target of JDP2 in the suppression of cell proliferation

Individual Activity Anomaly Estimation in Operating Rooms Based on Time-Sequential Prediction

Proceedings of the 19th World Congress on Medical and Health Informatics Volume 310Series: Studies in Health Technology and InformaticsSurveillance videos of operating rooms have potential to benefit post-operative analysis and study. However, there is currently no effective method to extract useful information from the long and massive videos. As a step towards tackling this issue, we propose a novel method to recognize and evaluate individual activities using an anomaly estimation model based on time-sequential prediction. We verified the effectiveness of our method by comparing two time-sequential features: individual bounding boxes and body key points. Experiment results using actual surgery videos show that the bounding boxes are suitable for predicting and detecting regional movements, while the anomaly scores using key points can hardly be used to detect activities. As future work, we will be proceeding with extending our activity prediction for detecting unexpected and urgent events

Recognition of Instrument Passing and Group Attention for Understanding Intraoperative State of Surgical Team

Appropriate evaluation of the intraoperative state of a surgical team is essential for the improvement of teamwork and hence a safe surgical environment. Traditional methods to evaluate intraoperative team states such as interview and self-check questionnaire on each surgical team member often require human efforts, which are time-consuming and can be biased by individual recall. One effective solution is to analyze the surgical video and track the important team activities, such as whether the members are complying with the surgical procedure or are being distracted by unexpected events. However, due to the complexity of the situations in an operating room, identifying the team activities without any human effort remains challenging. In this work, we propose a novel approach that automatically recognizes and quantifies intraoperative activities from surgery videos. As a first step, we focus on recognizing two activities that especially involve multiple individuals: (a) passing of clean-packaged surgery instruments which is a representative interaction between the surgical technologists such as the circulating nurse and scrub nurse, and (b) group attention that may be attracted by unexpected events. We record surgical videos as input, and apply pose estimation and particle filters to extract individual's face orientation, body orientation, and arm raise. These results coupled with individual IDs are then sent to an estimation model that provides the probability of each target activity. Simultaneously, a person model is generated and bound to each individual, which describes all the involved activities along the timeline. We tested our method using videos of simulated activities. The results showed that the system was able to recognize instrument passing and group attention with F1 = 0.95 and F1 = 0.66, respectively. We also implemented a system with an interface that automatically annotated intraoperative activities along the video timeline, and invited feedback from surgical technologists. The results suggest that the quantified and visualized activities can help improve understanding of the intraoperative state of the surgical team

Crystal structure of A3B3 complex of V-ATPase from Thermus thermophilus

Vacuolar-type ATPases (V-ATPases) exist in various cellular membranes of many organisms to regulate physiological processes by controlling the acidic environment. Here, we have determined the crystal structure of the A3B3 subcomplex of V-ATPase at 2.8 Å resolution. The overall construction of the A3B3 subcomplex is significantly different from that of the α3β3 sub-domain in FoF1-ATP synthase, because of the presence of a protruding ‘bulge' domain feature in the catalytic A subunits. The A3B3 subcomplex structure provides the first molecular insight at the catalytic and non-catalytic interfaces, which was not possible in the structures of the separate subunits alone. Specifically, in the non-catalytic interface, the B subunit seems to be incapable of binding ATP, which is a marked difference from the situation indicated by the structure of the FoF1-ATP synthase. In the catalytic interface, our mutational analysis, on the basis of the A3B3 structure, has highlighted the presence of a cluster composed of key hydrophobic residues, which are essential for ATP hydrolysis by V-ATPases

Tensile properties of Zr70Ni16Cu6Al8 BMG at room and cryogenic temperatures

The mechanical behaviour in tension of a hypoeutectic Zr70Ni16Cu6Al8 Bulk Metallic Glass (BMG) was studied at room (295 K) and cryogenic temperatures (150 K and 77 K) using various strain rates between 10−4 and 10−1 s−1. The yield strength was found to increase at lower temperatures with average values increasing by 16%, from 1503 MPa at 295 K to 1746 MPa at 77 K. The Zr-based BMG was found to exhibit tensile plastic elongation of about 0.4% before fracture at room temperature and high strain rates (10−1 s−1). Even higher tensile plasticity was recorded at low temperatures; plastic deformation was found highest at the intermediate temperature (150 K) reaching remarkable plastic strains in the order of 3.9%, while values up to 1.5% were recorded at 77 K. The lateral surface of the tensile specimens was observed in-situ during deformation using a high frame rate camera offering interesting insights with regard to the deformation mechanisms. Room temperature plasticity occurred through the formation and interaction of several nucleated shear bands before critical failure, while at intermediate and liquid nitrogen temperatures, most of the plastic deformation was accommodated through stable flow within a single shear band

Synthesis and In Vitro Assessment of pH-Sensitive Human Serum Albumin Conjugates of Pirarubicin

In a previous study, we reported on the development of a synthetic polymer conjugate of pirarubicin (THP) that was formed via an acid-labile hydrazone bond between the polymer and the THP. However, the synthetic polymer itself was non-biodegradable, which could lead to unexpected adverse effects. Human serum albumin (HSA), which has a high biocompatibility and good biodegradability, is also a potent carrier for delivering antitumor drugs. The objective of this study was to develop pH-sensitive HSA conjugates of THP (HSA-THP), and investigate the release of THP and the cytotoxicity under acidic conditions in vitro for further clinical development. HSA-THP was synthesized by conjugating maleimide hydrazone derivatives of THP with poly-thiolated HSA using 2-iminothiolane, via a thiol-maleimide coupling reaction. We synthesized two types of HSA-THP that contained different amounts of THP (HSA-THP2 and HSA-THP4). Free THP was released from both of the HSA conjugates more rapidly at an acidic pH, and the rates of release for HSA-THP2 and HSA-THP4 were similar. Moreover, both HSA-THPs exhibited a higher cytotoxicity at acidic pH than at neutral pH, which is consistent with the effective liberation of free THP under acidic conditions. These findings suggest that these types of HSA-THPs are promising candidates for further development