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51.
Popliteal-based filleted lower leg musculocutaneous free-flap coverage of a hemipelvectomy defect. 总被引:1,自引:0,他引:1
A 33-year-old man suffered from locally recurrent malignant fibrous histiocytoma of his left thigh unresponsive to previous excision, radiation therapy, chemotherapy, and hyperthermic treatment. He underwent radical hemipelvectomy for cure. Because of extensive tumor involvement, a free flap consisting of his distal left leg based on the popliteal artery was utilized to close the defect. Both the tibia and fibula were removed from their periosteal sheaths, and the foot was excised from the flap. The popliteal artery and vein were anastomosed to the iliac vessels. The flap survived, and the patient was discharged home after physical rehabilitation. We suggest that uninvolved portions of the distal leg may be utilized as a free flap to successfully close hemipelvectomy defects in selected patients when conventional pedicle flaps are unavailable. 相似文献
52.
Nazar J. Hussein Thomas Mbimba Asaad A. Al-Adlaan Mohammad Y. Ansari Fatima A. Jaber Scott McDermott Takhar Kasumov Fayez F. Safadi 《Journal of cellular biochemistry》2020,121(1):284-298
Trafficking protein particle complex 9 (TRAPPC9) is a major subunit of the TRAPPII complex. TRAPPC9 has been reported to bind nuclear factor κB kinase subunit β (IKKβ) and NF-kB-inducing kinase (NIK) where it plays a role in the canonical and noncanonical of nuclear factor-κB (NF-kB) signaling pathways, receptively. The role of TRAPPC9 in protein trafficking and cytoskeleton organization in osteoclast (OC) has not been studied yet. In this study, we examined the mRNA expression of TRAPPC9 during OC differentiation. Next, we examined the colocalization of TRAPPC9 with cathepsin-K, known to mediate OC resorption suggesting that TRAPPC9 mediates the trafficking pathway within OC. To identify TRAPPC9 protein partners important for OC-mediated cytoskeleton re-organization, we conducted immunoprecipitation of TRAPPC9 in mature OCs followed by mass spectrometry analysis. Our data showed that TRAPPC9 binds various protein partners. One protein with high recovery rate is L-plastin (LPL). LPL localizes at the podosomes and reported to play a crucial role in actin aggregation thereby actin ring formation and OC function. Although the role of LPL in OC-mediated bone resorption has not fully reported in detail. Here, first, we confirmed the binding of LPL to TRAPPC9 and, then, we investigated the potential regulatory role of TRAPPC9 in LPL-mediated OC cytoskeleton reorganization. We assessed the localization of TRAPPC9 and LPL in OC and found that TRAPPC9 is colocalized with LPL at the periphery of OC. Next, we determined the effect of TRAPPC9 overexpression on LPL recruitment to the actin ring using a viral system. Interestingly, our data showed that TRAPPC9 overexpression promotes the recruitment of LPL to the actin ring when compared with control cultures. In addition, we observed that TRAPPC9 overexpression reorganizes actin clusters/aggregates and regulates vinculin recruitment into the OC periphery to initiate podosome formation. 相似文献
53.
D.?C.?DrakeEmail author B.?Maritz S.?M.?Jacobs C.?J.?Crous A.?Engelbrecht A.?Etale M.?J.?Fourie D.?G.?Furniss S.?L.?Scott S.?Parusnath D.?R.?Tye 《Hydrobiologia》2013,712(1):1-4
The biological and physico-chemical structure of near bottom habitats located under densely growing submerged vegetation, and their significance in the functioning of whole aquatic ecosystems, are very little known due to difficulties in sampling. Corer-type samplers, believed to be the best in littoral studies, do not work properly in such places, because their tube opening is easily clogged by plant shoots, acting as a stopper. In order to overcome this problem, an alteration to the shape of the tube ending is proposed. This can be done by its trimming at an accurate angle, or by fitting (permanently or interchangeably) a metal collar made of stainless steel to its end, so that the ending would resemble the shape of a needle. The modification can be applied to virtually all corer samplers. It was found to be efficient while sampling sediment cores for the purposes of both hydrobiological and paleolimnological studies on heavily overgrown macrophyte-dominated water ecosystems. 相似文献
54.
We report the potential phylogenetic utility of DNA sequence data from the last 700 bp of a ca. 1-kb intron of the MADS-box gene pistillata from a sampling of Sphaerocardamum species and other Brassicaceae. These results are compared with nrDNA ITS and the chloroplast trnL intron for the same taxa to demonstrate the potential phylogenetic utility of this pistillata intron and to identify potential historically independent sequences for an ongoing study of relationships within Sphaerocardamum. Analyses of the DNA sequence data for Brassicaceae indicated that pairwise divergences and potentially informative characters were higher in the pistillata intron (0.6-30.8%, 284 characters) and ITS (0-24%, 94 characters) than in the chloroplast trnL intron (0-4.2%, 17 characters). A comparison of Sphaerocardamum sequences identified low divergences and numbers of informative characters for trnL intron (0-2.4%, 1 character) and nrDNA ITS (0-2.5%, 2 characters) and substantially more variation among the pistillata sequences (0.15-3.7%, 19 characters). Phylogenetic analyses of these pistillata sequences fully resolve ingroup relationships without character conflict. Results of pistillata PCR amplifications from a broader dicot sample showed that some primers may be useful in amplifying orthologous pistillata sequences. Ultimately this pistillata intron may be a valuable source of phylogenetic characters at lower taxonomic levels. 相似文献
55.
Myosin associated with the male germ cells of angiosperms interacts with actin, promoting transport of the non-motile generative
and later sperm cells in the pollen tube. Myosin localizing on the sperm cell plasma membrane seems negligible in Plumbago, as reflected by the absence of: (i) anti-myosin labeling using immunoelectron microscopy, (ii) sperm motility on actin matrices,
and (iii) electrophoretic movement changes after addition of antibody. Sperm cells injected directly into actively streaming
Nitella internodal cells, however, follow actin bundles and their movement is sensitive to ATP and Mg2+. This may be based on simple charge binding since negatively charged latex beads also migrate on actin, whereas neutral or
positively-charged latex beads do not. Sperm cells are negatively charged according to capillary microelectrophoresis, whereas
killed sperm cells, which are positively charged do not migrate. The sperm cell that normally fertilizes the egg has a higher
calculated charge (8.277 × 103 esu/cm2) compared with the sperm cell that fuses with the central cell (6.120 × 103 esu/cm2).
Received: 15 December 1998 / Accepted: 21 January 1999 相似文献
56.
57.
Gemma L. Moir-Meyer John F. Pearson Felicity Lose Rodney J. Scott Mark McEvoy John Attia Elizabeth G. Holliday Paul D. Pharoah Alison M. Dunning Deborah J. Thompson Douglas F. Easton Amanda B. Spurdle Logan C. Walker The Australian National Endometrial Cancer Study Group The Hunter Community Study Studies of Epidemiology Risk Factors in Cancer Heredity 《Human genetics》2015,134(3):269-278
58.
D W Carr Z E Hausken I D Fraser R E Stofko-Hahn J D Scott 《The Journal of biological chemistry》1992,267(19):13376-13382
The type II cAMP-dependent protein kinase (PKA) is localized to specific subcellular environments through binding of the dimeric regulatory subunit (RII) to anchoring proteins. Subcellular localization is likely to influence which substrates are most accessible to the catalytic subunit upon activation. We have previously shown that the RII-binding domains of four anchoring proteins contain sequences which exhibit a high probability of amphipathic helix formation (Carr, D. W., Stofko-Hahn, R. E., Fraser, I. D. C., Bishop, S. M., Acott, T. E., Brennan, R. G., and Scott J. D. (1991) J. Biol. Chem. 266, 14188-14192). In the present study we describe the cloning of a cDNA which encodes a 1015-amino acid segment of Ht 31. A synthetic peptide (Asp-Leu-Ile-Glu-Glu-Ala-Ala-Ser-Arg-Ile-Val-Asp-Ala-Val-Ile-Glu-Gln-Val -Lys-Ala-Ala-Tyr) representing residues 493-515 encompasses the minimum region of Ht 31 required for RII binding and blocks anchoring protein interaction with RII as detected by band-shift analysis. Structural analysis by circular dichroism suggests that this peptide can adopt an alpha-helical conformation. Both Ht 31 (493-515) peptide and its parent protein bind RII alpha or the type II PKA holoenzyme with high affinity. Equilibrium dialysis was used to calculate dissociation constants of 4.0 and 3.8 nM for Ht 31 peptide interaction with RII alpha and the type II PKA, respectively. A survey of nine different bovine tissues was conducted to identify RII binding proteins. Several bands were detected in each tissues using a 32P-RII overlay method. Addition of 0.4 microM Ht 31 (493-515) peptide to the reaction mixture blocked all RII binding. These data suggest that all anchoring proteins bind RII alpha at the same site as the Ht 31 peptide. The nanomolar affinity constant and the different patterns of RII-anchoring proteins in each tissue suggest that the type II alpha PKA holoenzyme may be specifically targeted to different locations in each type of cell. 相似文献
59.
In social environments, decisions not only determine rewards for oneself but also for others. However, individual differences in pro-social behaviors have been typically studied through self-report. We developed a decision-making paradigm in which participants chose from card decks with differing rewards for themselves and charity; some decks gave similar rewards to both, while others gave higher rewards for one or the other. We used a reinforcement-learning model that estimated each participant''s relative weighting of self versus charity reward. As shown both in choices and model parameters, individuals who showed relatively better learning of rewards for charity – compared to themselves – were more likely to engage in pro-social behavior outside of a laboratory setting indicated by self-report. Overall rates of reward learning, however, did not predict individual differences in pro-social tendencies. These results support the idea that biases toward learning about social rewards are associated with one''s altruistic tendencies. 相似文献
60.
Ethical Considerations for Outcome‐adaptive Trial Designs: A Clinical Researcher's Perspective 下载免费PDF全文
Scott Brian Saxman 《Bioethics》2015,29(2):59-65
In a typical comparative clinical trial the randomization scheme is fixed at the beginning of the study, and maintained throughout the course of the trial. A number of researchers have championed a randomized trial design referred to as ‘outcome‐adaptive randomization.’ In this type of trial, the likelihood of a patient being enrolled to a particular arm of the study increases or decreases as preliminary information becomes available suggesting that treatment may be superior or inferior. While the design merits of outcome‐adaptive trials have been debated, little attention has been paid to significant ethical concerns that arise in the conduct of such studies. These include loss of equipoise, lack of processes for adequate informed consent, and inequalities inherent in the research design which could lead to perceptions of injustice that may have negative implications for patients and the research enterprise. This article examines the ethical difficulties inherent in outcome‐adaptive trials. 相似文献