Bone Mass,Bone Microstructure and Biomechanics in Patients with Hand Osteoarthritis

The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.     

参芪胶囊的鉴别与含量测定方法研究

对参区胶囊中黄芪、人参、当归、知母、黄连等味药进行了薄层鉴别。并对黄连中小檗碱进行了薄层光密度法测定，方法灵敏，重现性好，回收率１００％，相对标准偏差ＲＳＤ％＝２．０（ｎ＝６）。     

Time in Motion: Qualities of Temporality Within Psychotherapeutic Psychodynamic Counselling

Our relationship to time is both a developmental and a relational one; an inter- and intra-psychic experience. Exploring how the theories of Freud, Klein, Winnicott, and their successors offer explanations of how the psychoanalytic subject develops and sustains a concept of time and the factors that may hinder this, this essay suggests that different qualities of time, such as continuity, rhythm, repetition and interruption, can reveal themselves through the client's transferential and countertransferential relationship with the therapist. Using fictionalized clinical examples it explores how a bodily felt experience of time was thought about by the therapist/author using Laban movement analysis to support a client in ‘working through’ early material that felt stuck. The exploration of a client's perspective is brought in through the writings of the activist Passerini on her psychoanalytic treatment (cited by Baraitser in Enduring Time) and her experience of trauma's capacity to stop time. The essay also looks at how psychoanalytic ideas of temporality challenge the ‘recruiting’ of time by the wider culture to create more time-efficient late-capitalist subjects but by using ideas from movement studies and a Lacanian influenced time register it is suggested that cultural attacks on subjective experiences of temporality could be challenged within therapy. It is hoped the essay encourages the therapist to become alert to the manifestations of different temporal experiences within the therapeutic relationship and to develop a creative, embodied language with which to explore it with the client.     

The Accuracy of Incident Vertebral Fracture Detection in Children Using Targeted Case-Finding Approaches

Vertebral fractures are clinically important sequelae of a wide array of pediatric diseases. In this study, we examined the accuracy of case-finding strategies for detecting incident vertebral fractures (IVF) over 2 years in glucocorticoid-treated children (n = 343) with leukemia, rheumatic disorders, or nephrotic syndrome. Two clinical situations were addressed: the prevalent vertebral fracture (PVF) scenario (when baseline PVF status was known), which assessed the utility of PVF and low lumbar spine bone mineral density (LS BMD; Z-score <−1.4), and the non-PVF scenario (when PVF status was unknown), which evaluated low LS BMD and back pain. LS BMD was measured by dual-energy X-ray absorptiometry, vertebral fractures were quantified on spine radiographs using the modified Genant semiquantitative method, and back pain was assessed by patient report. Forty-four patients (12.8%) had IVF. In the PVF scenario, both low LS BMD and PVF were significant predictors of IVF. Using PVF to determine which patients should have radiographs, 11% would undergo radiography (95% confidence interval [CI] 8–15) with 46% of IVF (95% CI 30–61) detected. Sensitivity would be higher with a strategy of PVF or low LS BMD at baseline (73%; 95% CI 57–85) but would require radiographs in 37% of children (95% CI 32–42). In the non-PVF scenario, the strategy of low LS BMD and back pain produced the highest specificity of any non-PVF model at 87% (95% CI 83–91), the greatest overall accuracy at 82% (95% CI 78–86), and the lowest radiography rate at 17% (95% CI 14–22). Low LS BMD or back pain in the non-PVF scenario produced the highest sensitivity at 82% (95% CI 67–92), but required radiographs in 65% (95% CI 60–70). These results provide guidance for targeting spine radiography in children at risk for IVF. © 2021 American Society for Bone and Mineral Research (ASBMR).     

Assembly properties and applications of a new exopolymeric compound excreted by Pseudoalteromonas antarctica NF3

The self assembly properties and applications of an exopolymeric compound (EC) of a glycoprotein character excreted by a new Gram-negative species, Pseudoalteromonas antarctica NF₃, have been reviewed. This compound exhibited surface-active properties in water, with a concentration of 0.20 mg ml^-1 being the key value associated with its physicochemical properties. Unsonicated EC aqueous dispersions showed the coexistence of concentric multilamellar and small unilamellar aggregates by transmission electron microscopy (TEM). Sonication of these dispersions revealed that each lamellae of the initial multilamellar structures were made up of various subunits coiled coils. As for the ability of this exopolymeric biomaterial to coat phosphatidylcholine (PC) liposomes and to protect these vesicles against different surfactants, freeze-fracture TEM micrographs of liposome/EC aggregates revealed that the addition of the EC to liposomes led to the formation of a film (polymer adsorbed onto the bilayers) that coated very well the PC bilayers. The complete coating was already achieved at a PC : EC weight ratio of about 9 :1. An increasing resistance of PC liposomes to surfactants (in particular sodium dodecyl sulfate) occurred as the proportion of EC in the system rose, although this effect was more effective at low EC proportions (PC : EC weight ratios from 9 : 1 to 8 : 2). Although a direct dependence was found between the growth of the enveloping structure and the resistance of the coated liposomes to be affected by the surfactants, the best protection occurred when this structure was a thin film of about 20-25 nm formed by nine to ten layers of about 2-3 nm.     

Changes in morphology of starch-based prothestic thermoplastic material during enzymatic degradation

This work evaluates the structural changes of an interpenetrated starch thermoplastic blend withstanding different enzymatic α-amylase degradation periods (up to 200 days), and establishes the relationships between the kinetics degradation rate and the structure of the material. It characterises the different stages of the enzymatic degradation process on starch/ethylenevinyl-alcohol blends, based on the attack of the connected starch domains that can be accessed by the enzymatic solution. The completely encapsulated starch particles remain practically unchanged. Furthermore, it was also found that the enzymatic degradation process was limited after 100 days of immersion. In order to understand such phenomenon several techniques were used, namely differential scanning calorimetry, contact-angle measurements, high-performance liquid chromatography, Fourier transform infrared spectrometry, scanning electron microscopy and atomic force microscopy. The materials were evaluated with respect to the enzymatic degradation rate, surface morphology and degradation behaviour. The results show that the ethylene-vinylalcohol phase wraps the starch domains, preventing the respective degradation. Consequently, the degraded material in the solution comes only from the starch particles that could be reached by the enzyme.     

Quantitative chemical mapping of sodium acrylate- and N-vinylpyrrolidone-enhanced alginate microcapsules

Alginate microcapsules enclosing recombinant cells secreting therapeutic products have been used successfully to treat several murine models of human diseases. The mechanical and chemical properties of these alginate capsules can be improved by the addition and in situ photopolymerization of sodium acrylate and N-vinylpyrrolidone in the alginate capsule. The purpose of this modification was to form additional covalent cross-links. In this work we have used scanning transmission X-ray microscopy (STXM) to probe the nature and location of the chemical modifications in the modified capsules by comparison with unmodified capsules. Analysis of X-ray image sequences and selected area spectra has been used to map the calcium gradient in capsules, to identify the presence of polyacrylate throughout the capsules and the localization of poly-N-vinylpyrrolidone in the outer regions of the alginate capsules. The differences in the spatial distributions of these species have led to better understanding of the chemical modifications that provide a mechanically more stable capsule structure.     

Associations between Auditory Capacity,Speech and Language,Level of Communication and Parental Assessment of Children with Cochlear Implant

168 children with cochlear implants were assessed as regards to auditory capacity, level of speech and language and communicative skills. The assessments were made by speech and language pathologists and parents. The purpose of the study was to analyse the associations between the four areas and furthermore to analyse associations between professional and parental assessments. The children were assessed with the Tait Video Analysis, the receptive part of the Reynell Test, a phonological test and a vocabulary test. The four objective tests were analysed for potential associations between results. In addition, potential associations between the results of the four tests and parental assessment of their child's auditory capacity (CAP) and speech intelligibility (SIR) were investigated. The Gamma Test and the Fisher's Exact Test were used on the ordinal and categorized data sets, respectively. The results of all the four auditory and structural speech and language tests were positively associated with each other (Gamma coefficients >0.8 and p values <0.001), which strengthens the validity of the individual tests and substantiates the observed results. Parental assessments were positively associated with the results of the four objective tests, which shows that parents are valid reporters of the level of their child's auditory, as well as speech and language development.     

Evaluation of interfacial properties of hyaluronan coated poly(methylmethacrylate) intraocular lenses

Polymethylmethacrylate intraocular lenses (IOLs) were surface-modified by the linking of a overlayer of hyaluronan. In vitro experiments show that the hydrophilic HA overlayer prevents fibroblasts adhesion and greatly reduces Staphyloccous epidermidis adhesion to the IOL surface. To gain insights into the interfacial properties of untreated and hyaluronan-coated PMMA IOLs, force-distance curves were obtained by atomic force microscopy, using standard and modified tips. These measurements allow clear appreciation of the marked difference between the mechanical and chemico-physical properties at the aqueous interface of the uncoated and hyaluronan-coated lenses.     

Trends in hip fracture rates in Canada: An age‐period‐cohort analysis

Age‐standardized rates of hip fracture in Canada declined during the period 1985 to 2005. We investigated whether this incidence pattern is explained by period effects, cohort effects, or both. All hospitalizations during the study period with primary diagnosis of hip fracture were identified. Age‐ and sex‐specific hip fracture rates were calculated for nineteen 5‐year age groups and four 5‐year calendar periods, resulting in 20 birth cohorts. The effect of age, calendar period, and birth cohort on hip fracture rates was assessed using age‐period‐cohort models as proposed by Clayton and Schiffers. From 1985 to 2005, a total of 570,872 hospitalizations for hip fracture were identified. Age‐standardized rates for hip fracture have progressively declined for females and males. The annual linear decrease in rates per 5‐year period were 12% for females and 7% for males (both p < 0.0001). Significant birth cohort effects were also observed for both sexes (p < 0.0001). Cohorts born before 1950 had a higher risk of hip fracture, whereas those born after 1954 had a lower risk. After adjusting for age and constant annual linear change (drift term common to both period and cohort effects), we observed a significant nonlinear birth cohort effect for males (p = 0.0126) but not for females (p = 0.9960). In contrast, the nonlinear period effect, after adjustment for age and drift term, was significant for females (p = 0.0373) but not for males (p = 0.2515). For males, we observed no additional nonlinear period effect after adjusting for age and birth cohort, whereas for females, we observed no additional nonlinear birth cohort effect after adjusting for age and period. Although hip fracture rates decreased in both sexes, different factors may explain these changes. In addition to the constant annual linear decrease, nonlinear birth cohort effects were identified for males, and calendar period effects were identified for females as possible explanations.