AIMTo provide a “patient-normalized” parameter in the proximal forearm.METHODSSixty-three cadaveric upper extremities from thirty-five cadavers were studied. A muscle splitting approach was utilized to locate the posterior interosseous nerve (PIN) at the point where it emerges from beneath the supinator. The supinator was carefully incised to expose the midpoint length of the nerve as it passes into the forearm while preserving the associated fascial connections, thereby preserving the relationship of the nerve with the muscle. We measured the transepicondylar distance (TED), PIN distance in the forearm’s neutral rotation position, pronation position, supination position, and the nerve width. Two individuals performed measurements using a digital caliper with inter-observer and intra-observer blinding. The results were analyzed with the Wilcoxon-Mann-Whitney test for paired samples.RESULTSIn pronation, the PIN was within two confidence intervals of 1.0 TED in 95% of cases (range 0.7-1.3 TED); in neutral, within two confidence intervals of 0.84 TED in 95% of cases (range 0.5-1.1 TED); in supination, within two confidence intervals of 0.72 TED in 95% of cases (range 0.5-0.9 TED). The mean PIN distance from the lateral epicondyle was 100% of TED in a pronated forearm, 84% in neutral, and 72% in supination. Predictive accuracy was highest in supination; in all cases the majority of specimens (90.47%-95.23%) are within 2 cm of the forearm position-specific percentage of TED. When comparing right to left sides for TEDs with the signed Wilcoxon-Mann-Whitney test for paired samples as well as a significance test (with normal distribution), the P-value was 0.0357 (significance - 0.05) indicating a significant difference between the two sides.CONCLUSIONThis “patient normalized” parameter localizes the PIN crossing a line drawn between the lateral epicondyle and the radial styloid. Accurate PIN localization will aid in diagnosis, injections, and surgical approaches.

Objective. The purpose of this study is to describe the three-dimensional morphometry of the brachialis muscle at its distal attachment to the ulna. Methods. Fifty cadaveric elbows were dissected and the brachialis distal insertion was isolated on the ulna bone and probed with a three-dimensional digitizer, to create a three-dimensional model of the footprint. Measurements and analysis of each footprint shape were recorded and compared based on gender and size. Results. There was significant gender difference in the surface length (P= 0.002) and projected length (P= 0.001) of the brachialis footprint. The shapes of the footprint also differed among the specimens. Conclusion. The shape of the brachialis muscle insertion differed among all the specimens without significant variation in gender or sides. There was also a significant difference in muscle length between males and females with little difference in the width and surface area. Significance. The information obtained from this study is important for kinematic understanding and surgical procedures around the elbow joint as well as the understanding of the natural age related anatomy of the brachialis footprint morphology.

Abnormal meal timing, like skipping breakfast and late-night snacking, is associated with obesity in humans. Disruption of daily eating rhythms also contributes to obesity in mice. When fed high-fat diet, male C57BL/6J mice have disrupted eating behavior rhythms and they become obese. In contrast to obesity-prone C57BL/6J mice, some inbred strains of mice are resistant to high-fat diet-induced obesity. In this study, we sought to determine whether there are distinct effects of high-fat feeding on daily eating behavior rhythms in obesity-prone and obesity-resistant male mice. Male obesity-prone (C57BL/6J and 129X1/SvJ) and obesity-resistant (SWR/J and BALB/cJ) mice were fed low-fat diet or high-fat diet for 6 weeks. Consistent with previous studies, obesity-prone male mice gained more weight and adiposity during high-fat diet feeding than obesity-resistant male mice. The amplitude of the daily rhythm of eating behavior was markedly attenuated in male obesity-prone mice fed high-fat diet, but not in obesity-resistant males. In contrast, high-fat feeding did not differentially affect locomotor activity rhythms in obesity-prone and obesity-resistant male mice. Together, these data suggest that regulation of the daily rhythm of eating may underlie propensity to develop diet-induced obesity in male mice.

There have been a large number of experimental methods for purifying and analyzing proteins from the sample of interest. Determination of protein concentration is often the key step and is common to many applications in protein research and life sciences. The most commonly used quantitative techniques to measure the protein concentration are Amino acid analysis, Biuret assay, Bradford assays, Folin-Lowry assay, Bicinchoninic (BCA) assays, UV absorbance assays and Antibody-based assays such as ELISA and Western Blotting. Some of the qualitative methods that are used to detect different types of proteins and amino acids are Ninhydrin test, Xanthoproteic test, Millon's test, Sulfur test, Hopkins-Cole test, and Nitroprusside test. Chromatographic analysis can also be carried out on an either qualitative or quantitative basis to purify complex protein mixtures based on their properties such as size, solubility, charge, hydrophobicity and bio-specific interaction. Selection of these assays is based upon the ease of performance, range of concentrations, sensitivity, and interfering substances contained in the complex mixture. The purpose of this review is to provide an assessment of commonly used chromatographic and colorimetric methods for the determination of protein concentration.