The effect of crutches,an orthosis TheraTogs,and no walking aids on the recovery of gait in a patient with delayed healing post hip fracture: A case report

Accelerated rehabilitation following hip fracture and joint replacement, including early unrestricted weight-bearing and muscle strengthening, has gained importance in hastening functional recovery and hospital discharge. The influence of walking aids on these parameters is sparsely investigated. In this case report, we document the effect of walking with crutches; an orthotic garment and strapping system, TheraTogs; and no walking aids over 3–4-week periods on walking speed, trunk sway, and muscle activity measured with electromyography (EMG). The patient was a 49-year-old female showing delayed healing following a conservatively treated avulsion fracture of the greater trochanter 12 weeks previously with a 14-year history of total hip arthroplasty. EMG analysis showed muscle activity increased with TheraTogs and decreased with crutches compared with walking with no aids. Walking speed improved at a faster rate in the TheraTogs phase than in the crutches phase and reduced in no-walking-aids phase. Mean speed (SD) for each phase was: crutches 1.11 (0.08) m/s, TheraTogs 1.35 (0.11) m/s, and no-aids 1.19 (0.14) m/s. Trunk sway increased in the crutch and no-aids phases, and became more stable in the TheraTogs phase. In this patient, function and recovery rate of all measured parameters increased more in the TheraTogs phase than the crutches or no-aids phase. This may be because muscle activity was facilitated enabling active support of recovering structures.     

Correlation between secosteroid-induced vitamin D receptor activity in melanoma cells and computer-modeled receptor binding strength

To define the interaction of novel secosteroids produced by the action of cytochrome P450scc with vitamin D receptor (VDR), we used a human melanoma line overexpressing VDR fused with enhanced green fluorescent protein (EGFP) and tested the ligand induced translocation of VDR from the cytoplasm to the nucleus. Hydroxyderivatives of vitamin D(3) with a full length (D(3)) side chain and hydroxy-secosteroids with a shortened side chain (pD) stimulated VDR translocation and inhibited proliferation, however, with different potencies. In general the D(3) were more potent than pD analogues. Molecular modeling of the binding of the secosteroids to the VDR genomic binding pocket (G-pocket) correlated well with the experimental data for VDR translocation. In contrast, docking scores for the non-genomic binding site of the VDR were poor. In conclusion, both the length of the side chain and the number and position of hydroxyl groups affect the activation of VDR by novel secosteroids.     

A model of the viscoelastic behavior of flowable resin composites prior to setting

Objective

The aim of this study is to develop fractional derivative models for the assessment of viscoelastic properties related to handling characteristics of dental resin composites belonging to two classes: flowable (Revolution Formula 2 and Filtek Ultimate) and posterior “bulk-fill” flowable base (Smart Dentin Replace).

Methods

Rheological measurements on all materials tested in this study were performed using dynamic oscillatory rheometer at temperature of 23 °C. A parallel plates module with a diameter of 20 mm was used to measure the properties of the resin composites tested. We developed two models to describe the obtained data: the generalized Newton model and the generalized Zener model (the so-called three parameter model). Both models contain fractional derivatives of Riemann–Liouville type. By determining the parameters of the model we were able to fit experimental data with high accuracy.

Results

Our results show that flowable “bulk-fill” resin-composite material (SDR) has distinct properties as compared to other two flowable resin composite materials (Revolution Formula 2 and Filtek Ultimate). Thus, previously found SDR properties as “bulk-fill” flowable base results in the fact that it is described by generalized Zener model (i.e., it has properties of solid like viscoelastic material).

Significance

Our model may be used to predict behavior of tested composites in different flow conditions. The SDR has initially small almost constant complex viscosity showing that it has good self-leveling property.     

Impact of triple pelvic osteotomy on contact stress pressure distribution in the hip joint

Purpose

We studied changes of contact stress distribution in the hip joint after Tonnis triple pelvic osteotomy applied in the treatment of dysplasia and hip joint incongruence in adolescents.

Methods

In a group of 75 patients, 54 (72 %) female, who underwent surgery by triple pelvic osteotomy in adolescence for developmental disorder of the hip and avascular necrosis of the femoral head, a three-dimensional hip joint model was used based on the radiography of the pelvis with hips. The following biomechanical parameters were calculated: resultant hip force normalised to body weight (R/Wb), inclination of the resultant hip force (θ−R), the position of the stress pole (θ), peak contact hip stress (Pmax), and peak contact hip stress normalised to body weight (Pmax/Wb). Gait quality was also assessed.

Results

After surgery the Wiberg CE angle was increased by 17.85° (114 %), resultant hip force normalised to body weight (R/Wb) was decreased by 0.107 (3.3 %), the position of the stress pole was shifted medially by 27.59° (63.5 %), and peak contact hip stress normalised to body weight (Pmax/Wb) was decreased by 2249.74 (55.9 %). Waddling gait was reduced from 17 (23.9 %) to four cases (5.6 %). All changes were statistically highly significant (p<0.01).

Conclusions

The effect of Tonnis triple pelvic osteotomy lies in the improvement of stress distribution across the acetabular cartilage of the hip joint, thus slowing down the degenerative damage of the hip joint.     

Biological evaluation of selected 3,4‐dihydro‐2(1H)‐quinoxalinones and 3,4‐dihydro‐1,4‐benzoxazin‐2‐ones: Molecular docking study

In order to investigate new potential therapeutically active agents, we investigated the biological properties of two small libraries of quinoxalinones and 1,4‐benzoxazin‐2‐ones. The results obtained showed that compounds 5 , 9–11 have good cytotoxic activity against HeLa cells where the lowest IC₅₀ value (10.46 ± 0.82 μM/mL) was measured for compound 10 . Additionally, the most active compounds ( 5 , 9 – 11 ) showed much better selectivity for MRC‐5 cells (up to 17.4) compared to cisplatin. In vitro evaluation of the inhibition of the enzyme α‐glucosidase showed that compounds 10 and 11 exert significant inhibition of the enzyme at 52.54 ± 0.09 and 40.09 ± 0.49 μM, respectively. Competitive experiments with ethidium bromide (EB) indicated that all tested compounds have affinity to displace EB from the EB‐DNA complex through intercalation, suggesting good competition with EB (K_sv = (3.1 ± 0.2), (5.1 ± 0.1), (5.6 ± 0.2), and (6.3 ± 0.2) × 10³ M^?1). A molecular docking study was also performed to better understand the binding modes and to conclude the structure–activity relationships of the synthesized compounds.

     

Reshaping of T-lymphocyte compartment in adult prepubertaly ovariectomised rats: A putative role for progesterone deficiency

This study explores the role of ovarian hormones in the phenotypic shaping of peripheral T-cell pool over the reproductive lifespan of rats. For this purpose, 2-month-old prepubertally ovariectomised (Ox) rats, showing oestrogen and progesterone deficiency, and 11-month-old Ox rats, exhibiting only progesterone deficiency, were examined for thymus output, and cellularity and composition of major TCRαβ+ peripheral blood lymphocyte (PBL) and splenocyte subsets. Although ovariectomy increased thymic output in both 2- and 11-month-old rats, the count of both CD4+ and CD8+ PBLs and splenocytes increased only in the former. In the blood and spleen of 11-month-old Ox rats only the count of CD8+ cells increased. Although ovariectomy affected the total CD4+ count in none of the examined compartments from the 11-month-old rats, it increased CD4+FoxP3+ PBL and splenocyte relative proportions over those in the age-matched controls. The age-related differences in the cellularity and the major subset composition in Ox rats were linked to the differences in the ovarian steroid hormone levels registered in 2- and 11-month-old rats. The administration of progesterone to Ox rats during the seven days before the sacrificing confirmed contribution of this hormone deficiency to the ovariectomy-induced changes in the TCRαβ+ PBL and splenocyte pool from 11-month-old rats. The expansion of the CD8+ splenocyte subset in the 11-month-old Ox rats reflected increases in cellularity of memory and, particularly, naïve cells. This was due to greater thymic output of CD8+ cells and homeostatic proliferation than apoptosis in 11-month-old Ox rats when compared with age-matched sham-Ox control rats. The homeostatic changes within CD8+ splenocyte pool from 11-month-old Ox rats, most likely, reflected the enhanced splenic IL-7 and TGF-β mRNA expression. Overall, in adult female rats, circulating oestrogen and progesterone provide maintenance of T-cell counts, a diversity of T-cell repertoire, and the main T-cell subset composition in the periphery. Progesterone deficiency affects mainly the CD8+ lymphocyte compartment through increasing thymic CD8+ cell export and upsetting homeostatic regulation within the CD8+ splenocyte pool. These alterations were reversible through progesterone supplementation.