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761.
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Background

Open total extrusion of the talus without concomitant fracture is an extremely rare injury. We present 6-year follow-up data of a patient treated using a temporary spanning external fixator and less invasive single K-wire fixation.

Case presentation

A 55-year-old Asian man who had a totally extruded talus without fracture underwent immediate reimplantation surgery. A spanning external fixator with single antegrade K-wire fixation was applied to maintain the reimplanted talus. During 6 years of follow-up, he could walk without aids and could squat, corresponding to an American Orthopaedic Foot and Ankle Society score of 85. We found that the suspect lesion that was evident at 6 months after surgery had disappeared at 12 months postoperatively on the basis of sequential follow-up magnetic resonance imaging. There was no evidence of osteonecrosis of the dislocated talus at the final follow-up.

Conclusions

In patients with a totally extruded talus, a surgical strategy including immediate reimplantation of the talus and a temporary spanning fixator with single K-wire fixation might be useful to allow early mobilization around the ankle joint and to prevent additional damage of the foot without significant complications.
  相似文献   
763.
In plants, multiple calmodulin (CaM) isoforms exist in an organism which vary in their primary structures in as much as 32 residues out of their 148 amino acids. These CaM isoforms show differences in their expression patterns and/or target enzyme activation ability. To further understand the biological significance of CaM isoforms, we examined whether CaM isoforms act on specific regulatory targets. In gel overlay assays on various soybean tissue extracts, surprisingly, two soybean CaM isoforms (SCaM-1 and SCaM-4) did not show significant differences in their target binding protein profiles, although they exhibited minor differences in their relative target binding affinities. In addition, both SCaM isoforms not only effectively bound five known plant CaMBPs, but also showed competitive binding to these proteins. Finally, immunolocalization experiments with the SCaM proteins in sections of various tissues using specific antibodies revealed similar distribution patterns for the SCaM isoforms except for root tissues, which indicates that the SCaM isoforms are concomitantly expressed in most plant tissues. These results suggest that CaM isoforms may compete for binding to CaMBPs in vivo. This competitive nature of CaM isoforms may allow modulation of Ca(2+)/CaM signaling pathways by virtue of relative abundance and differential target activation potency.  相似文献   
764.

Background  

A Brucella eradication program has been executed in Korea. To effectively prevent and control brucellosis, a molecular method for genetic identification and epidemiological trace-back must be established. As part of that, the MLVA typing assay was evaluated and applied to B. abortus isolates for analyzing the characteristics of the regional distribution and relationships of foreign isolates.  相似文献   
765.
Galanin is a neuropeptide expressed in the central and peripheral nervous systems, where it regulates various processes including neuroendocrine release, cognition, and nerve regeneration. Three G-protein coupled receptors (GPCRs) for galanin have been discovered, which is the focus of efforts to treat diseases including Alzheimer’s disease, anxiety, and addiction. To understand the basis of the ligand preferences of the receptors and to assist structure-based drug design, we used cryo-electron microscopy (cryo-EM) to solve the molecular structure of GALR2 bound to galanin and a cognate heterotrimeric G-protein, providing a molecular view of the neuropeptide binding site. Mutant proteins were assayed to help reveal the basis of ligand specificity, and structural comparison between the activated GALR2 and inactive hβ2AR was used to relate galanin binding to the movements of transmembrane (TM) helices and the G-protein interface.

Galanin is a neuropeptide expressed in the central and peripheral nervous systems, where it regulates various processes including neuroendocrine release, cognition, and nerve regeneration. This cryo-electron microscopy study shows how galanin interacts with one of its three human receptor proteins, GALR2, and reveals the basis of the selectivity of this GPCR for Gq.  相似文献   
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767.
The oleaginous microalga Aurantiochytrium sp. KRS101 was cultivated in enzymatic hydrolysates of alkali-pretreated empty palm fruit bunches (EFBs), without prior detoxification process. The maximal levels of lipid and docosahexaenoic acid synthesized were 12.5 and 5.4 g L?1 after cultivation for 36 h. Similar lipid levels were also obtained via simultaneous saccharification and cultivation. The results suggested that EFB is a promising source for production of useful lipids by the microalgal strain.  相似文献   
768.
Leptin is an adipocyte-secreted hormone that binds hypothalamic receptors and potently decreases food intake. Leptin receptor defects in homozygous mutant Zucker fatty ( fa/fa) rats lead to massive obesity, hyperphagia, decreased energy expenditure, and insulin resistance, while the phenotype of heterozygous ( Fa/fa) lean rats lies between lean ( Fa/Fa) and obese ( fa/fa) rats. Whether heterezygotes exhibit specific changes in lipid metabolism in a diet-responsive manner is not clear. Thus, the specific aim of this study was to test whether the presence of one fa allele modulates lipid metabolism and leptin, and whether these effects are exacerbated by high-fat diet. We demonstrate that the presence of one fa allele significantly increases lipogenesis in adipose tissue assessed by glycerol-3-phosphate dehydrogenase (GPDH) and fatty acid synthase (FAS) activities. FAS is more responsive to high-fat diets than GPDH in Fa/fa rats. Adipose tissue leptin levels are significantly higher in fat pads of Fa/fa compared to Fa/Fa rats. Moreover, Fa/fa rats fed high-fat diet show an additional two-fold increase in leptin levels compared to wild type rats on the same diet. Collectively, these results indicate that the presence of one fa allele increase adipocyte lipogenic enzyme activities, which results in hyperleptinemia concurrent with increased adiposity.  相似文献   
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