How to rapidly abolish knee extension deficit after injury or surgery: a practice-changing video pearl from the Scientific Anterior Cruciate Ligament Network International (SANTI) Study Group

Knee extension deficit is frequently observed after anterior cruciate ligament reconstruction or rupture and other acute knee injuries. Loss of terminal extension often occurs because of hamstring contracture and quadriceps inactivation rather than mechanical intra-articular pathology. Failure to regain full extension in the first few weeks after anterior cruciate ligament reconstruction is a recognized risk factor for adverse long-term outcomes, and therefore, it is important to try to address it. In this technical note, a simple, rapid, and effective technique to help regain full knee extension and abolish quadriceps activation failure is described

Hypoxia leads to significant changes in alternative splicing and elevated expression of CLK splice factor kinases in PC3 prostate cancer cells

© 2018 The Author(s). Background: Mounting evidence suggests that one of the ways that cells adapt to hypoxia is through alternative splicing. The aim of this study was firstly to examine the effect of hypoxia on the alternative splicing of cancer associated genes using the prostate cancer cell line PC3 as a model. Secondly, the effect of hypoxia on the expression of several regulators of splicing was examined. Methods: PC3 cells were grown in 1% oxygen in a hypoxic chamber for 48 h, RNA extracted and sent for high throughput PCR analysis at the RNomics platform at the University of Sherbrooke, Canada. Genes whose exon inclusion rate PSI (ψ) changed significantly were identified, and their altered exon inclusion rates verified by RT-PCR in three cell lines. The expression of splice factors and splice factor kinases in response to hypoxia was examined by qPCR and western blotting. The splice factor kinase CLK1 was inhibited with the benzothiazole TG003. Results: In PC3 cells the exon inclusion rate PSI (ψ) was seen to change by >25% in 12 cancer-associated genes; MBP, APAF1, PUF60, SYNE2, CDC42BPA, FGFR10P, BTN2A2, UTRN, RAP1GDS1, PTPN13, TTC23 and CASP9 (caspase 9). The expression of the splice factors SRSF1, SRSF2, SRSF3, SAM68, HuR, hnRNPA1, and of the splice factor kinases SRPK1 and CLK1 increased significantly in hypoxia. We also observed that the splice factor kinase CLK3, but not CLK2 and CLK4, was also induced in hypoxic DU145 prostate, HT29 colon and MCF7 breast cancer cell lines. Lastly, we show that the inhibition of CLK1 in PC3 cells with the benzothiazole TG003 increased expression of the anti-apoptotic isoform caspase 9b. Conclusions: Significant changes in alternative splicing of cancer associated genes occur in prostate cancer cells in hypoxic conditions. The expression of several splice factors and splice factor kinases increases during hypoxia, in particular the Cdc-like splice factor kinases CLK1 and CLK3. We suggest that in hypoxia the elevated expression of these regulators of splicing helps cells adapt through alternative splicing of key cancer-associated genes. We suggest that the CLK splice factor kinases could be targeted in cancers in which hypoxia contributes to resistance to therapy

Site-selective incorporation and ligation of protein aldehydes

The incorporation of aldehyde handles into proteins, and subsequent chemical reactions thereof, is rapidly proving to be an effective way of generating homogeneous, covalently linked protein constructs that can display a vast array of functionality. In this review, we discuss methods for introducing aldehydes into target proteins, and summarise the ligation strategies for site-selective modification of proteins containing this class of functional handles

Dysphagia after anterior cervical spine surgery: a systematic review of potential preventative measures

Background context Anterior cervical spine surgery is one of the most common spinal procedures performed around the world, but dysphagia is a frequent postoperative complication. Many factors have been associated with an increased risk of swallowing difficulties, including multilevel surgery, revision surgery, and female gender. Purpose The objective of this study was to review and define potential preventative measures that can decrease the incidence of dysphagia after anterior cervical spine surgery. Study design This was a systematic literature review. Methods A systematic review in the Medline database was performed. Articles related to dysphagia after anterior cervical spine surgery and potential preventative measures were included. Results Twenty articles met all inclusion and exclusion criteria. These articles reported several potential preventative measures to avoid postoperative dysphagia. Preoperative measures include performing tracheal exercises before the surgical procedure. Intraoperative measures can be summarized as avoiding a prolonged operative time and the use of recombinant human bone morphogenetic protein in routine anterior cervical spine surgery, using small and smoother cervical plates, using anchored spacers instead of plates, application of steroid before wound closure, performing arthroplasty instead of anterior cervical fusion for one-level disease, decreasing tracheal cuff pressure during medial retraction, using specific retractors, and changing the dissection plan. Conclusions Current literature supports several preventative measures that may decrease the incidence of postoperative dysphagia. Although the evidence is limited and weak, most of these measures did not appear to increase other complications and can be easily incorporated into a surgical practice, especially in patients who are at high risk for postoperative dysphagia. © 2014 Elsevier Inc. All rights reserved.Anterior cervical spine surgery is one of the most common spinal procedures performed around the world, but dysphagia is a frequent postoperative complication. 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