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Previous studies have reported that osteophytes in the cervical vertebrae may cause immobility, neck stiffness, osteoarthritis, headaches, nerve entrapment syndromes, and compression of the vertebral artery. Our objective was to explore the osteophytes' expression on zygapophyseal joints C3–C7. This is a cross-sectional observational skeletal study. The study sample comprised 273 human skeletons of both sexes, aged 20–93, housed at the Natural History Museum, OH, USA. A grading system assessed the presence and severity of osteophytosis on the zygapophyseal joints. The chi-square test (SPSS 25.0) examined the association between osteophytes and demographic factors. The level of significance (α) was set at .05. The highest prevalence of osteophytes was found on C5 vertebra, the lowest on C7. On vertebrae C3, C4, C6, the rate of moderate and severe osteophytes found on the superior and inferior facets were comparable. Moderate and severe degrees of osteophytes were observed more frequently on the superior facets, whereas, on vertebra C7, osteophytes were found on the inferior facet joints. Osteophytes' prevalence was significantly higher in the elderly compared to the younger population. Osteophytes in the C3–C7 zygapophyseal joints are age-dependent. No significant sex and ethnic differences were observed. Vertebra C5 was most prone to develop osteophytes, most probably due to its location in the cervical lordotic peak, C5 in the superior ZF; C7 in the inferior ZF are significant (p = .05). The zygapophyseal joints of C7 were least frequent overall, yet, the C7 inferior facets had significantly more moderate–severe osteophytes compared to other cervical vertebrae.  相似文献   

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Segmental instability, characterized by excessive or aberrant movement of the vertebrae can be assessed quantitatively using mechanical characteristics within a region of minimal resistance called the neutral zone. The diagnosis of instability is often used to decide whether or not to surgically fuse the vertebrae. Alterations in flexion/extension posture cause changes in both contact area and spacing between articulating facets that may lead to changes in the mechanical response of the functional spinal unit (FSU) within the neutral zone. This investigation quantified neutral zone (NZ) length under anterior and posterior shear loading and the influence of posture on the shear NZ characteristics of the vertebral joint. Thirty porcine cervical FSUs (15 C34 and 15 C56) were tested. Endplate area was calculated from measurements of the exposed endplates while facet angles were measured from X-rays taken in the transverse plane. Specimens were exposed to a 300 N compressive preload followed by a test to determine flexion/extension NZ limits. These limits were used as target angles during shear passive tests performed in extended and flexed postures. Displacement rate during shear passive tests was 0.2 mm/s and five cycles of anterior–posterior shear were performed to a target of ±400 N in a randomized order of extended, neutral and flexed postures. Shear NZ length and average stiffness were quantified. Stiffness within the shear NZ was 67 N/mm in the neutral posture. Extended postures produced a 37% (p < 0.0001) increase in shear stiffness within the NZ compared to both flexed and neutral postures. Posture did not influence shear NZ length. Therefore, a true region of zero stiffness does not exist during shear loading with a baseline compressive load. Neutral zone length for the porcine FSU exposed to shear load was not influenced, despite known changes in facet articulation, by changing posture. Average stiffness increased likely as a result of increased contact area and force in extension. The results from this investigation demonstrate that postural deviation of the vertebral joint is not likely a significant confounding factor when assessing segmental stability.  相似文献   

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Background: Memory performance is a cognitive function that is affected by environmental, genetic and socioeconomic factors, as well as by weight status.

Aim: To evaluate the association of weight status at 2?years of age with the memory performance of children at 4–5?years of age.

Subjects and methods: A cross-sectional study that used baseline data (2012) and data from two follow-up periods (2014 and 2016) of the PREDI Cohort Study. Participants were mother–child pairs 4–5?years after delivery who were seen between July 2016 and August 2017. The children’s memory performance was evaluated individually using a validated Brazilian instrument.

Results: Of the 203 children included in the study, 117 (57.6%), 52 (25.6%) and 34 (16.8%) had low, moderate and high memory performance, respectively. After adjusting for potential confounders, children with a BMI > 85th percentile had 3.33-times higher odds of exhibiting lower memory performance at 4–5?years of age than those with a BMI ≤ 85th percentile. In addition to the children’s BMI at 2?years of age, mother’s education was another independent determinant of children’s memory performance. There was a progressive increase in the odds of children having lower memory performance at 4–5?years of age as the mother’s education decreased.

Conclusion: Primary prevention of overweight and management of cognitive functions may be important strategies to improve the cognitive development of children in the future.  相似文献   

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A number of different surgical interventions can be used for treating antero-medial osteoarthritis (AMOA) of the knee and this choice can present challenges for patient's decision-making. Patients with AMOA can undergo Total Knee Replacement (TKR), Unicompartmental Knee Replacement (UKR) or High Tibial Osteotomy (HTO) for the same pathology. However many uncertainties still exist as to deciding which operation is best for individual patients and the Orthopaedic community has failed to systematically compare treatment options. The relative lack of scientifically based evidence has impacted on the ability to provide clear guidelines on treatment choice, patient suitability and direct patient preference for treatment. This paper, using available evidence, discusses the issue and offers some suggestions for future development.  相似文献   

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Information

Refresher course in surgical anatomy and surgical techniques of the spine marseille, France, 27–31 May, 1991  相似文献   

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Previous studies demonstrated that no significant relationships exist between salivary and serum IL-6 in resting conditions and following exercise and that appropriate saliva collection procedures allow to avoid analytical drawbacks. This investigation aimed to: (a) compare the effects of two methods of saliva collection on IL-6 assay; (b) search for correlation between salivary and serum IL-6 in resting and post-exercise conditions; (c) evaluate the IL-6 response to isometric contractions. Seventeen sedentary subjects and fifteen athletes underwent one blood and two salivary draws: saliva was collected chewing on cotton salivettes and using a plastic straw (SA method and ST method, respectively). Afterwards, the athletes only completed a fatiguing isometric exercise of the knee extensors and blood and saliva were sampled after the exercise. In the entire group (n = 32), ST method produced higher IL-6 levels than SA method and serum sampling. The exercise elicited significant responses of lactate, serum IL-6, salivary IL-6 (by ST method): salivary IL-6 values using the ST collection method were higher at each sampling point than with the SA method. The correlation analyses applied to both resting levels in the entire group and absolute changes above baseline in the athlete group showed that: (1) no significant relationships exist between serum and salivary IL-6 levels; (2) the greater the salivary IL-6 measurement, the higher the resultant inaccuracy of the SA method; (3) significant correlations exist between isometric force and mechanical fatigue during exercise and peaks of lactate and serum IL-6. These data provided demonstration of a cotton-interference effect for the results of salivary IL-6 assay and confirmed the lack of significant correlation between salivary and serum IL-6 in resting and post-exercise conditions.  相似文献   

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A single 3-min all-out cycling test can be used to estimate the power asymptote (critical power, CP) and the curvature constant (W') of the power-duration relationship for severe-intensity exercise. It was hypothesized that when exercise immediately preceding the 3-min all-out test was performed CP would systematically reduce the W' without affecting the CP. Seven physically active males completed 3-min all-out cycling tests in randomized order immediately preceded by: unloaded cycling (control); 6-min moderate; 6-min heavy; 2-min severe (S2); or 4-min severe (S4) intensity exercise. The CP was estimated from the mean power output over the final 30 s of the test and the W' was estimated as the power-time integral above end-test power. There were no significant differences in the CP between control (279 ± 62), moderate (275 ± 52), heavy (286 ± 66 W), S2 (274 ± 55), or S4 (273 ± 65 W). The W' was significantly lower (P < 0.05) in S2 (11.5 ± 2.5) and S4 (8.9 ± 2.2) than in control (16.3 ± 2.3), moderate (17.2 ± 2.4) and heavy (15.6 ± 2.3 kJ). These results support the notion that the W' is predictably depleted only at a power output >CP whereas the CP is independent of the mechanisms which reduce W'.  相似文献   

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The isoflavone, daidzein is a biologically active, plant-derived compound that interacts with estrogen receptors. Data from previous studies have suggested that daidzein exerts beneficial effects in many diseases; however, as an endocrine disrupter, it may also alter the functioning of the endocrine system. Data regarding the effect of daidzein on the morphofunctional and histological parameters of the hypothalamic–pituitary–adrenal (HPA) system is still lacking. Therefore, using the newCAST stereological software, we investigated the effects of chronic (21 days) daidzein treatment on corticotropin-releasing hormone (CRH) neurons within the hypothalamus and corticotropes (ACTH cells) in the pituitary, while image analysis was employed to-examine the intensity of fluorescence of CRH in the median eminence (ME) and adrenocorticotropin hormone in the pituitary in adult orchidectomized (Ovx) rats. Circulating ACTH and corticosterone levels were also analyzed. This study showed that daidzein treatment decreased the volume density of CRH neurons within the paraventricular nucleus as well as CRH immunofluorescence in the ME. The total number of ACTH cells was decreased, while ACTH cell volume and the intensity of ACTH fluorescence were increased following daidzein treatment. Both ACTH and corticosterone blood levels were increased after daidzein administration. The results of performed experiments clearly demonstrate that volume density of CRH neurons; total number and volume of ACTH cells, as well as stress hormones levels are vulnerable to the effects of daidzein.  相似文献   

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Calcium phosphate (CaP) ceramics are widely used in bone tissue engineering due to their good osteoconductivity. The mechanical properties of CaP can be modified by the addition of small volume fractions of biodegradable polymers such as polycaprolactone (PCL). Nevertheless, it is also important to evaluate how the polymer content influences cell–material or cell–cell interactions because of potential consequences for bone regeneration and vascularization. In this study we assessed the general biocompatibilty of Ca-deficient hydroxyapatite (CDHA)–PCL disks containing nominally 11 and 24% polycaprolactone using human umbilical vein endothelial cells and human primary osteoblasts. Confocal microscopy showed that both CDHA–PCL variants supported the growth of both cell types. In terms of the endothelial cells grown on CDHA–PCL nanocomposites with 24% PCL, an increased expression of the endothelial marker vWF compared to CDHA–PCL with 11% PCL was observed in real-time polymerase chain reaction analysis. In addition to monocultures, co-cultures of outgrowth endothelial cells, derived from peripheral blood, and primary osteoblasts were assessed as an example of a more complex test system for bone regeneration and vascularization. Constructs based on CDHA with different PCL contents were investigated with regard to the formation of microvessel-like structures induced by the co-culture process using confocal microscopy and quantitative image analysis. Furthermore, the osteogenic differentiation of the co-culture was assessed. As a result, more pre-vascular structures were observed after 1 week on the CDHA–PCL disks with 24% PCL, whereas after 4 weeks of culture the extent of microvessel-like structure formation was slightly higher on the CDHA with 11% PCL. In contrast to this, variation of PCL content had no effect on the osteogenic differentiation in the co-culture.  相似文献   

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Background: Analyses of birth parameters worldwide reveal relatively high variability over time, often related to socioeconomic factors.

Aim: The aim was to determine the existence of inter-generational changes in birth parameters in Kraków (Poland) in recent years and factors responsible.

Subjects and methods: This research analysed data on 7800 newborns (e.g. body length and weight) and their parents in the years 1985–2010. The significance of differences was calculated using ANOVA. To examine the potential effect of environmental factors, MANOVA were used.

Results: In the case of birth weight no significant changes were observed. A significant decreasing tendency in birth length from the beginning of the 21st century was shown – this observation is quite rare. Accordingly, BMI increased significantly in the 2000s. A decreasing tendency was observed for head circumference.

Conclusion: In the analysed period Poland experienced significant socio-economic changes, which could have partly contributed to the observed changes. Some of the observed trends in birth parameters are recent phenomena and it seems necessary to continue the research to confirm if these changes form a steady trend or are only temporary. Tracking any phenomena related to the development is important for the determination of disruptive factors and the reduction of their adverse effects.  相似文献   


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Several bi-modular hip prostheses exhibit an elevated number of fretting-related postoperative complications most probably caused by excessive micromotions at taper connections. This study investigated micromotions at the stem–neck interface of two different designs: one design (Metha, Aesculap AG) has demonstrated a substantial number of in vivo neck fractures for Ti–Ti couplings, but there are no documented fractures for Ti–CoCr couplings. Conversely, for a comparable design (H-Max M, Limacorporate) with a Ti–Ti coupling only one clinical failure has been reported. Prostheses were mechanically tested and the micromotions were recorded using a contactless measurement system.For Ti–Ti couplings, the Metha prosthesis showed a trend towards higher micromotions compared to the H-Max M (6.5 ± 1.6 μm vs. 3.6 ± 1.5 μm, p = 0.08). Independent of the design, prostheses with Ti neck adapter caused significantly higher interface micromotions than those with CoCr ones (5.1 ± 2.1 μm vs. 0.8 ± 1.6 μm, p = 0.001). No differences in micromotions between the Metha prosthesis with CoCr neck and the H-Max M with Ti neck were observed (2.6 ± 2.0 μm, p = 0.25).The material coupling and the design are both crucial for the micromotions magnitude. The extent of micromotions seems to correspond to the number of clinically observed fractures and confirm the relationship between those and the occurrence of fretting corrosion.  相似文献   

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Objective: To develop tissue engineering scaffolds consisting of self-assembling KLD-12 polypeptide/TGF-β1 nanofiber gel, for the induction of mesenchymal stem cell (MSCs) differentiation into nucleus pulposus (NP)-like cells. Methods: The release of TGF-β1 from KLD-12 polypeptide gels containing varying TGF-β1 concentrations was detected by ELISA. MSCs were isolated with a density gradient method and their differentiation into NP-like cells was analyzed in KLD-12 polypeptide/TGF-β1- or KLD-12 polypeptide control nanofiber-gel 3D-cultures. The Alcianblue method, Real-time quantitative PCR (RT-qPCR), and immunocytochemistry were used to measure the expression of extracellular matrix (ECM) molecules, such as aggrecan, glycosaminoglycans (GAGs), and type II collagen. Results: ELISA results documented favorable time-dependent release characteristics of TGF-β1 in the KLD-12 polypeptide/TGF-β1 gel scaffolds. The results of CCK-8 cell proliferation assay showed the TGF-β1 containing scaffolds induced higher growth rate in MSCs compared to the control group. Calcein-AM/PI fluorescent staining showed: the cells in the gel grew well, maintaining the circular shape of cells, and the spindle and fusiform shape of cells on the gel edges. The cell viability displayed a survival rate of 89.14% ± 2.468 for the TGF-β1 group with no significant difference between the two groups at 14 d of culture. The production of ECM was monitored showing higher expression of GAGs in the TGF-β1 group (P < 0.01) with highest amounts at 10 d and 14 d compared to 4 d and 7 d (P < 0.05). Real-time PCR results revealed that the expression levels of collagen II and aggrecan mRNA were higher in the TGF-β1 group (P < 0.05). Finally, immunocytochemical staining of collagen II confirmed the higher expression levels. Conclusion: A scaffold containing a KLD-12 polypeptide/TGF-β1-nanofiber gel and MSCs differentiated into NP-like cells is able to produce ECM and has the potential to serve as a three-dimensional (3-D) support scaffold for the filling of early postoperative residual cavities and the treatment of intervertebral disc degeneration.  相似文献   

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