Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

DNA-induced increase in the α-helical content of C/EBP and GCN4

Leucine zipper proteins comprise a recently identified class of DNA binding proteins that contain a bipartite structural motif consisting of a "leucine zipper" dimerization domain and a segment rich in basic residues responsible for DNA interaction. Protein fragments encompassing the zipper plus basic region domains (bZip) have previously been used to determine the conformational and dynamic properties of this motif. In the absence of DNA, the coiled-coil portion is alpha-helical and dimeric, whereas the basic region is flexible and partially disordered. Addition of DNA containing a specific recognition sequence induces a fully helical conformation in the basic regions of these fragments. However, the question remained whether the same conformational change would be observed in native bZip proteins where the basic regions might be stabilized in an alpha-helical conformation even in the absence of DNA, through interactions with portions of the protein not included in the bZip motif. We have now examined the DNA-induced conformational transition for an intact bZip protein, GCN4, and for the bZip fragment of C/EBP with two enhancers that are differentially symmetric. Our results are consistent with the induced helical fork model wherein the basic regions are largely flexible in the absence of DNA and become fully helical in the presence of the specific DNA recognition sequence

GLP-1 receptor agonism affects hepatic expression of genes involved in VLDL production, lipogenesis, and lipid homeostasis.

<p><i>E3L</i> mice were fed HFD for 13 weeks. The last 4 weeks, mice were treated with either vehicle (HFD control), CNTO3649 (0.3 or 1.0 mg/kg/day) or exendin-4 (15 or 50 μg/kg/day). As a control for HFD feeding, an additional group of mice was included fed a chow diet that received vehicle (chow control). Livers were isolated from 7 h fasted mice, and mRNA was extracted from liver pieces. mRNA values of indicated genes were normalized to <i>Cyclo</i> and <i>Hprt</i> mRNA levels. Data were calculated as fold difference as compared with the HFD control group. Values are means ± SEM for at least 6 mice per group. *P<0.05, **P<0.01, ***P<0.001 compared to HFD controls.</p

GLP-1 receptor agonism reverses high fat diet-induced hepatic steatosis.

<p><i>E3L</i> mice were fed HFD for 13 weeks. The last 4 weeks, mice were treated with either vehicle (HFD control), CNTO3649 (0.3 or 1.0 mg/kg/day) or exendin-4 (15 or 50 μg/kg/day). As a control for HFD feeding, an additional group of mice was included fed a chow diet that received vehicle (chow control). Livers were isolated from 7 h fasted mice, liver pieces were homogenized, and triglycerides, cholesterol and phospholipids were determined as nmol per mg protein. Values are means ± SEM for at least 6 mice per group. <i>*</i>P<0.05, <i>**</i>P<0.01, <i>***</i>P<0.001 compared to HFD controls.</p

GLP-1 receptor agonism reduces hepatic VLDL-TG and VLDL-apoB production without affecting VLDL particle composition.

<p><i>E3L</i> mice were fed a HFD for 22 weeks. The last 4 weeks, mice were treated with either vehicle (HFD control), CNTO3649 (1.0 or 3.0 mg/kg/day) or exendin-4 (15 or 50 μg/kg/day). As a control for HFD feeding, an additional group of mice fed a chow diet was included that received vehicle (chow control). After 7 h fasting, mice were injected with Tran³⁵S label (t = −30 min) and Triton WR-1339 (t = 0 min). Blood was drawn at the indicated time points and plasma TG concentrations were determined (A, B). VLDL-TG production rate was calculated as µmol/h from the slopes of the TG-time curves of the individual mice (C). At t = 120 min, mice were exsanguinated, and VLDL was isolated by density gradient ultracentrifugation. ³⁵S-activity was determined, and VLDL-apoB production rate was calculated as dpm.h⁻¹ (D). The VLDL-TG production rate to VLDL-apoB production rate ratio was calculated as nmol/dpm (E). The content of triglycerides, cholesterol, phospholipids and protein in VLDL was determined and calculated as % of total mass (F). Values are means ± SEM for at least 6 mice per group. <i>*</i>P<0.05, <i>**</i>P<0.01, <i>***</i>P<0.001 compared to HFD controls. TG: triglycerides; TC: total cholesterol; PL: phospholipids; Pro: protein.</p