Soft tissue displacement over pelvic anatomical landmarks during 3-D hip movements

The position, in a pelvis-embedded anatomical coordinate system, of skin points located over the following anatomical landmarks (AL) was determined while the hip assumed different spatial postures: right and left anterior superior and posterior superior iliac spines, and the sacrum. Postures were selected as occurring during walking and during a flexion–extension and circumduction movement, as used to determine the hip joint centre position (star-arc movement). Five volunteers, characterised by a wide range of body mass indices (22–37), were investigated. Subject-specific MRI pelvis digital bone models were obtained. For each posture, the pose of the pelvis-embedded anatomical coordinate system was determined by registering this bone model with points digitised over bony prominences of the pelvis, using a wand carrying a marker-cluster and stereophotogrammetry. The knowledge of how the position of the skin points varies as a function of the hip posture provided information regarding the soft tissue artefact (STA) that would affect skin markers located over those points during stereophotogrammetric movement analysis. The STA was described in terms of amplitude (relative to the position of the AL during an orthostatic posture), diameter (distance between the positions of the AL which were farthest away from each other), and pelvis orientation. The STA amplitude, exhibited, over all postures, a median [inter-quartile] value of 9[6] and 16[11] mm, for normal and overweight volunteers, respectively. STA diameters were larger for the star-arc than for the walking postures, and the direction was predominantly upwards. Consequent errors in pelvic orientation were in the range 1–9 and 4–11 degrees, for the two groups respectively.     

Incidence of soft tissue sarcoma in Taiwan: A nationwide population-based study (2007–2013)

BackgroundAsian studies on soft tissue sarcoma (STS) incidence, irrespective of the primary site, are scant.MethodsSTS data were acquired from the population-based 2007–2013 Taiwan Cancer Registry of the Health and Welfare Data Science Center, Taiwan. Histological subtype-, site-, sex-, and age-specific STS incidence rates were analyzed according to the 2013 classification of the World Health Organization.ResultsIn total, 11,393 patients with an age-standardized incidence rate (ASIR) of 5.62 (95% confidence interval, 5.51–5.73) per 100,000 person-years were identified. Overall, a male predominance (sex-standardized incidence rate ratio, 1.2) was noted, and the rate increased with age, peaking at >75 years. Approximately 30% of STSs occurred in connective, subcutaneous, and other soft tissues and 70% in other sites. In addition to connective, subcutaneous, and other soft tissues, the three most common primary sites were the stomach (15.9%), skin (14.3%), and small intestines (10.5%). Gastrointestinal stromal tumor was the most common subtype (29.2%; ASIR, 1.55/100,000 person-years), followed by liposarcoma (11.5%; ASIR, 0.63/100,000 person-years) and leiomyosarcoma (9.7%; ASIR, 0.53/100,000 person-years). Compared with relevant data from Western countries, the incidence rate of angiosarcomas was higher than that in other regions, whereas the incidence rates of leiomyosarcoma and Kaposi sarcoma were lower than those in other regions.ConclusionSTS incidence varied by histological subtype, sex, age, and primary site in an Asian population. Our results suggested regional and racial discrepancies in the incidence rates of certain STS subtypes.     

Wood-decay type and fungal guild dominance across a North American log transplant experiment

We incubated 196 large-diameter aspen (Populus tremuloides), birch (Betula papyrifera), and pine (Pinus taeda) logs on the FACE Wood Decomposition Experiment encompassing eight climatically-distinct forest sites in the United States. We sampled dead wood from these large-diameter logs after 2 to 6 y of decomposition and determined wood rot type as a continuous variable using the lignin loss/density loss ratio (L/D) and assessed wood-rotting fungal guilds using high-throughput amplicon sequencing (HTAS) of the ITS-2 marker. We found L/D values in line with a white rot dominance in all three tree species, with pine having lower L/D values than aspen and birch. Based on HTAS data, white rot fungi were the most abundant and diverse wood-rotting fungal guild, and soft rot fungi were more abundant and diverse than brown rot fungi in logs with low L/D values. For aspen and birch logs, decay type was related to the wood density at sampling. For the pine logs, decay type was associated with the balance between white and brown/soft rot fungi abundance and OTU richness. Our results demonstrate that decay type is governed by biotic and abiotic factors, which vary by tree species.     

Rolling adhesion of leukocytes on soft substrates: Does substrate stiffness matter?

Cell rolling on vascular endothelium under hydrodynamic blood flow is critical for realization of many physiological and pathological processes, such as inflammatory response and tumor metastasis. The blood-borne cells are in direct contact with the inner layer of endothelium, formed by a highly compliant layer of endothelial cells. The effect of endothelial stiffness on the adhesion and motion of rolling cells is poorly understood. Inspired by recent in vitro studies, here we implemented a computational method to model the specific adhesion of a rolling cell onto a soft substrate, subjected to a creeping shear flow. The substrate is modeled as an elastic half-space, coated with P- and E-selectin receptors with specific affinity for the complementary ligands located on the moving cell. Of particular importance is to predict the effect of substrate stiffness on cell adhesion and its kinematics and kinetics of motion. Simulation results show that the effect of substrate compliance is minimal when coated with P-selectin. Conversely, the trajectory of rolling cells on E-selectin coated substrates is sensitive to the substrate compliance. This is attributed to the moderation of binding forces applied by the soft substrate which leads to a higher average translational velocity of cells.     

Vibration settling time of the gastrocnemius remains constant during an exhaustive run in rear foot strike runners

In this study, vibrations of human gastrocnemius during an exhaustive run protocol are considered for analysis. Previous studies have shown increased vibration intensity and damping coefficient within the soft tissue with fatigue. The question of this study was to investigate if the vibration settling time remains constant during a prolonged running. Eleven semi-professional middle/long distance runners ran to exhaustion on a treadmill with their preferred constant speed (4.29 ± 0.33 m/s) for 3873 ± 1147 m. Vibration of the gastrocnemius lateralis, electrical activity of the tibialis anterior and the gastrocnemius medialis along with ground reaction force (GRF) were recorded. The results demonstrated significant increase in impact peak and loading rate, and the frequency content of the impact, with no significant change in active peak of the vertical GRF. Fatigue resulted in increased vibration intensity, damping coefficient, and energy dissipation of vibration with no change in vibration settling time. Furthermore, peak acceleration significantly linearly (R = 0.59) increased as a function of running time. The mean frequency of muscle activity of the gastrocnemius medialis and the intensity of muscle activity in TA significantly decreased. The results suggest that constant vibration settling time might either be an objective for muscle tuning which is more pronounced in fatigued state or a passive by-product of muscle function in running. Further studies are needed to address this point.     

Bioactive Xenicane Diterpenoids from the Taiwanese Soft Coral Asterospicularia laurae

Chemical investigation of the Taiwanese soft coral Asterospicularia laurae has led to the isolation of three new xenicane diterpenoids, named asterolaurins K–M ( 1 – 3 , resp.). Their chemical structures were determined through extensive spectroscopic analyses (¹H‐ and ¹³C‐NMR, ¹H,¹H‐COSY, HMBC, and NOESY). Compound 2 exhibited cytotoxic activity against HEp‐2, Daoy, MCF‐7, and WiDr tumor cells.     

Multilevel functional clustering analysis

Summary In this article, we investigate clustering methods for multilevel functional data, which consist of repeated random functions observed for a large number of units (e.g., genes) at multiple subunits (e.g., bacteria types). To describe the within- and between variability induced by the hierarchical structure in the data, we take a multilevel functional principal component analysis (MFPCA) approach. We develop and compare a hard clustering method applied to the scores derived from the MFPCA and a soft clustering method using an MFPCA decomposition. In a simulation study, we assess the estimation accuracy of the clustering membership and the cluster patterns under a series of settings: small versus moderate number of time points; various noise levels; and varying number of subunits per unit. We demonstrate the applicability of the clustering analysis to a real data set consisting of expression profiles from genes activated by immunity system cells. Prevalent response patterns are identified by clustering the expression profiles using our multilevel clustering analysis.     

The reactivity of cytochrome c with soft ligands.

The spectral changes caused by binding soft ligands to the cytochrome c iron and their correlation to ligand affinities support the hypothesis that the iron—methionine sulfur bond of this heme protein is enhanced by delocalization of the metal l₂, electrons into the empty 3d orbitals of the ligand atom. These findings also explain the unique spectrum of cytochrome c in the far red.