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The subsynovial connective tissue (SSCT) is a viscoelastic structure connecting the median nerve (MN) and the flexor tendons in the carpal tunnel. Increased strain rates increases stiffness in viscoelastic tissues, and thereby its capacity to transfer shear load. Therefore, tendon excursion velocity may impact the MN displacement. In carpal tunnel syndrome (CTS) the SSCT is fibrotic and may be ruptured, and this may affect MN motion. In this study, ultrasonography was performed on 14 wrists of healthy controls and 25 wrists of CTS patients during controlled finger motions performed at three different velocities. Longitudinal MN and tendon excursion were assessed using a custom speckle tracking algorithm and compared across the three different velocities. CTS patients exhibited significantly less MN motion than controls (p ≤ 0.002). While in general, MN displacement increased with increasing tendon excursion velocity (p ≤ 0.031). These findings are consistent with current knowledge of SSCT mechanics in CTS, in which in some patients the fibrotic SSCT appears to have ruptured from the tendon surface. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:483–487, 2015.  相似文献   
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Purpose

Neurofibromatosis type 1 (NF1) is a tumour suppressor syndrome and also a bone disease. In the craniofacial region, local skeletal deformities have been recorded in patients with NF1. Obvious syndrome-related alterations of the jaws are particularly conspicuous in the mandible. Here we aimed to analyse the mandibular alterations of NF1-affected individuals from orthopantomograms (OPGs).

Materials and Methods

This study analyses 358 OPGs of 358 patients (mean age, 34.63 years; range, 12.57–69.13 years). The OPGs of 179 patients of Caucasian origin with NF1 were investigated (mean age, 34.84 years; range, 12.83–68.89 years; 44.13% male, 55.86% female). The radiographic findings were compared to those obtained from OPGs of sex- and age-matched controls.

Results

Characteristic deformations of the bone regions of interest occur in NF1 patients, especially in patients with plexiform neurofibroma of trigeminal nerve. These findings are always one-sided. The co-occurrence of several skeletal deformations can be expected with very high probability in this patient group.

Conclusion

The radiological sign of the unilateral deformed mandible should be included in the diagnostic criteria for NF1. In addition to the diagnostic value in this syndrome, these findings are important for avoiding surgical complications in planned interventions in this region.  相似文献   
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The social interface between reproductive medicine and embryonic stem cell research has been investigated in a pilot study at a large IVF clinic in central China. Methods included observation, interviews with hospital personnel, and five in-depth qualitative interviews with women who underwent IVF and who were asked for their consent to the donation of embryos for use in medical (in fact human embryonic stem cell) research. This paper reports, and discusses from an ethical perspective, the results of an analysis of these interviews. The participants talked of extreme social pressure to become pregnant. Once they had a baby, 'spare' embryos lost practical significance due to the Chinese one-child policy. In the context of decision making about donating embryos to research, the women used the clinical distinctions between 'good and bad quality' embryos and also between frozen and transferred embryos, as guiding moral distinctions. In the absence of concrete information about what sort of research their embryos should be used for, the women interviewed either refused consent (for fear that the embryo would be given to another couple) or accepted, expressing motives of solidarity with other women in a similar situation. This reveals that they filled the knowledge gap with an image of research improving fertility treatment.  相似文献   
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Background

Chronic inflammation is common in cancer cachexia (CC) and directly involved in the atrophy seen in this condition. Recently, several groups have described a form of cardiomyopathy in CC animal models. Hence, we investigated the effect of simvastatin with its known anti-inflammatory and cardioprotective effects in a rat model of CC.

Methods

Juvenile Wister Han rats (weight approx. 200 g) were inoculated with Yoshida AH-130 hepatoma cells and treated once daily with 0.1, 1, 10 or 20 mg/kg/d simvastatin or placebo for 14 days. Body weight and body composition (NMR) were assessed at baseline and at the end of the study. Cardiac function was analysed by echocardiography at baseline and day 11.

Results

Tumour-bearing, placebo-treated rats lost 47.9 ± 3.8 g of their initial body weight. Treatment with 0.1, 1, 10 or 20 mg/kg/d simvastatin significantly reduced wasting by 39.6%, 47.6%, 28.5% and 35.4%, respectively (all p < 0.05 vs. placebo). This was mainly due to reduced atrophy of lean mass, i.e. muscle mass. Cardiac function was significantly improved, e.g. cardiac output (untreated sham: 78.9 mL/min) was severely impaired in tumour-bearing rats (42.4 mL/min) and improved by 1, 10 or 20 mg/kg/d simvastatin (62.2, 59.0 and 57.0 mL/min, respectively, all p < 0.05 vs. placebo). Most importantly, 10 or 20 mg/kg/d simvastatin reduced mortality (HR:0.16, 95%CI:0.04–0.76, p = 0.021 and HR:0.16, 95%CI:0.03–0.72, p = 0.017 vs placebo, respectively).

Conclusion

Simvastatin attenuated loss of body weight as well as muscle mass and improved cardiac function leading to improved survival in this CC model. Simvastatin may be beneficial in a clinical setting to treat CC.  相似文献   
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OBJECTIVE: To evaluate the recolonization pattern of Mutans streptococci (ms) on densely colonized teeth with fixed orthodontic appliances after treatment with a highly concentrated (36%) chlorhexidine varnish. MATERIALS AND METHODS: Healthy subjects (n = 19) with fixed orthodontic appliances and high bacterial ms counts in saliva were recruited. In order to establish a baseline registration, plaque adjacent to brackets was sampled and cultivated on Dentocult strips. Following professional tooth cleaning, chlorhexidine varnish was applied on all teeth for 8 minutes. The degree of recolonization with ms was assessed 2 weeks after varnish application in plaque around the brackets. For statistical analysis, the data were subjected to a repeated measures design. RESULTS: After 2 weeks, ms counts were reduced as compared to baseline values. However, the reduction only weakly met statistical significance (P = .049). CONCLUSIONS: The application of a highly concentrated chlorhexidine varnish in patients with fixed orthodontic appliances does not result in a distinct reduction of ms numbers 2 weeks after treatment.  相似文献   
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The PIDDosome is a multiprotein complex, composed by the p53-induced death domain protein 1 (PIDD1), the bipartite linker protein CRADD (also known as RAIDD) and the proform of caspase-2 that induces apoptosis in response to DNA damage. In the recent years, biallelic pathogenic variants in CRADD have been associated with a neurodevelopmental disorder (MRT34; MIM 614499) characterized by pachygyria with a predominant anterior gradient, megalencephaly, epilepsy and intellectual disability. More recently, biallelic pathogenic variants in PIDD1 have been described in a few families with apparently nonsydnromic intellectual disability. Here, we aim to delineate the genetic and radio-clinical features of PIDD1-related disorder. Exome sequencing was carried out in six consanguineous families. Thorough clinical and neuroradiological evaluation was performed for all the affected individuals as well as reviewing all the data from previously reported cases. We identified five distinct novel homozygous variants (c.2584C>T p.(Arg862Trp), c.1340G>A p.(Trp447*), c.2116_2120del p.(Val706Hisfs*30), c.1564_1565delCA p.(Gln522fs*44), and c.1804_1805del p.(Gly602fs*26) in eleven subjects displaying intellectual disability, behaviorial and psychiatric features, and a typical anterior-predominant pachygyria, remarkably resembling the CRADD-related neuroimaging pattern. In summary, we outlin`e the phenotypic and molecular spectrum of PIDD1 biallelic variants supporting the evidence that the PIDD1/CRADD/caspase-2 signaling is crucial for normal gyration of the developing human neocortex as well as cognition and behavior.Subject terms: Clinical genetics, Medical research  相似文献   
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