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Tracy Y Zhu James F Griffith Ling Qin Vivian WY Hung Tsz‐Ning Fong Sze‐Ki Au Xiao Lin Tang Anthony W Kwok Ping‐Chung Leung Edmund K Li Lai‐Shan Tam 《Journal of bone and mineral research》2013,28(4):794-806
The purpose of this work was to investigate the volumetric bone mineral density (vBMD), bone microstructure, and mechanical indices of the distal radius in female patients with rheumatoid arthritis (RA). We report a cross‐sectional study of 66 middle‐aged female RA patients and 66 age‐matched healthy females. Areal BMD (aBMD) of the hip, lumbar spine, and distal radius was measured by dual‐energy X‐ray absorptiometry (DXA). High‐resolution peripheral quantitative computed tomography (HR‐pQCT) was performed at the distal radius, yielding vBMD, bone microstructure, and mechanical indices. Cortical and trabecular vBMD were 3.5% and 10.7% lower, respectively, in RA patients than controls, despite comparable aBMD. Trabecular microstructural indices were –5.7% to –23.1% inferior, respectively, in RA patients compared to controls, with significant differences in trabecular bone volume fraction, separation, inhomogeneity, and structural model index. Cortical porosity volume and percentage were 128% and 93% higher, respectively, in RA patients, with stress being distributed more unevenly. Fourteen RA patients had exaggerated periosteal bone apposition primarily affecting the ulnovolar aspect of the distal radius. These particular patients were more likely to have chronic and severe disease and coexisting wrist deformity. The majority of the differences in density and microstructure between RA patients and controls did not depend on menstrual status. Recent exposure to glucocorticoids did not significantly affect bone density and microstructure. HR‐pQCT provides new insight into inflammation‐associated bone fragility in RA. It detects differences in vBMD, bone microstructure, and mechanical indices that are not captured by DXA. At the distal radius, deterioration in density and microstructure in RA patients involved both cortical and trabecular compartments. Excessive bone resorption appears to affect cortical more than trabecular bone at distal radius, particularly manifested as increased cortical porosity. Ulnovolar periosteal apposition of the distal radius is a feature of chronic, severe RA with wrist deformity. © 2013 American Society for Bone and Mineral Research. 相似文献
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The medial prefrontal cortex (mPFC) of humans and macaques is an integral part of the default mode network and is a brain region that shows increased activation in the resting state. A previous paper from our laboratory reported significantly increased firing rates of neurons in the macaque subgenual cingulate cortex, Brodmann area (BA) 25, during disengagement from a task and also during slow wave sleep [E.T. Rolls et al. (2003) J. Neurophysiology, 90, 134–142]. Here we report the finding that there are neurons in other areas of mPFC that also increase their firing rates during disengagement from a task, drowsiness and eye‐closure. During the neurophysiological recording of single mPFC cells (n = 249) in BAs 9, 10, 13 m, 14c, 24b and especially pregenual area 32, populations of neurons were identified whose firing rates altered significantly with eye‐closure compared with eye‐opening. Three types of neuron were identified: Type 1 cells (28.1% of the total population) significantly increased (mean + 329%; P ? 0.01) their average firing rate with eye‐closure, from 3.1 spikes/s when awake to 10.2 spikes/s when asleep; Type 2 cells (6.0%) significantly decreased (mean ?68%; P < 0.05) their firing rate on eye‐closure; and Type 3 cells (65.9%) were unaffected. Thus, in many areas of mPFC, implicated in the anterior default mode network, there is a substantial population of neurons that significantly increase their firing rates during periods of eye‐closure. Such neurons may be part of an interconnected network of distributed brain regions that are more active during periods of relaxed wakefulness than during attention‐demanding tasks. 相似文献
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Ellen Demurie Herbert Roeyers Dieter Baeyens Edmund Sonuga-Barke 《Research in developmental disabilities》2013,34(6):1870-1880
It has been shown that delayed consumable rewards are discounted to a higher degree than money, which has been referred to as the “domain effect”. Until now the effects of reward type on temporal discounting (TD) have mainly been studied in adults. Although there is evidence that children with attention-deficit/hyperactivity disorder (ADHD) tend to show steeper TD of money than typically developing peers or children with autism spectrum disorders (ASD), it remains untested whether the domain effect is also seen in children with ADHD and ASD. To explore this we compared TD of children (8–16 year) with ADHD, ASD and typically developing controls with five different reward types. Seventy-two participants with ADHD, 69 with ASD and 130 controls performed two hypothetical TD-tasks: a monetary TD-task and a TD-task with one of four alternative rewards (material rewards, rewarding activities, food, social rewards). TD was seen for all reward types, but the rate of discounting was steeper for food, praise and rewarding activities compared to money, and for food and praise compared to material rewards. For the ADHD and control groups, but not the ASD group, money and material rewards were equally highly discounted. High correlations between TD of money and of activities, food and material rewards were found. In conclusion, a domain effect was observed in typically developing children, as well as in children with ADHD or ASD, although the pattern was somewhat different for ASD children. Despite this domain effect, there is also evidence for a domain-general aspect in TD. 相似文献
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Bahiyah Abdullah Su Yen Khong Peng Chiong Tan 《International urogynecology journal》2016,27(7):1057-1062
Introduction
Cervicovaginal decubitus ulceration is a well-known complication of advanced pelvic organ prolapse (POP). There is no consensus for its management. This case series describes the outcome of using repeated vaginal packs soaked with oestrogen cream to reduce POP and promote decubitus ulcer healing. We aimed to investigate the speed of ulcer healing and endometrial safety with this regimen.Methods
This was a retrospective study of patients with stage 3 or 4 POP and intact uterus with decubitus ulcer who were planned for surgery that included hysterectomy after ulcer healing. Vaginal packs are replaced at least biweekly—or more frequently if extruded—until ulcer resolution.Results
Thirteen patients were studied. Mean age was 69?±?6 years and mean duration of menopause was 19?±?6 years. Nine patients had a single ulcer and four had multiple ulcers. Mean ulcer diameter was 2.8?±?1.5 cm and mean duration for ulcer healing was 26?±?14 days. Hysterectomy and pelvic floor reconstruction was performed a median of 5 (range 0–153) days after ulcer healing was first noted. Histopathological examination of the endometrium following hysterectomy showed three specimens with endocervical hyperplasia; one had concurrent proliferative endometrium, two had simple endometrial hyperplasia and another two had proliferative endometrium.Conclusion
Oestrogen-soaked vaginal packing is a viable option for managing a decubitus ulcer in advanced POP. We document a measurable impact on the endometrium with this short-term preoperative regimen. Further research is needed to evaluate its efficacy in promoting ulcer healing and endometrial safety.109.
Erik J. Kramer David W. Shearer Elliot Marseille Billy Haonga Joshua Ngahyoma Edmund Eliezer Saam Morshed 《World journal of surgery》2016,40(9):2098-2108
Background
Femoral shaft fractures are one of the most common injuries seen by surgeons in low- and middle-income countries (LMICs). Surgical repair in LMICs is often dismissed as not being cost-effective or unsafe, though little evidence exists to support this notion. Therefore, the goal of this study is to determine the cost of intramedullary nailing of femoral shaft fractures in Tanzania.Methods
We used micro-costing methods to estimate the fixed and variable costs of intramedullary nailing of femoral shaft fractures. Variable costs assessed included medical personnel costs, ward personnel costs, implants, medications, and single-use supplies. Fixed costs included costs for surgical instruments and administrative and ancillary staff.Results
46 adult femoral shaft fracture patients admitted to Muhimbili Orthopaedic Institute between June and September 2014 were enrolled and treated with intramedullary fixation. The total cost per patient was $530.87 (SD $129.99). The mean variable cost per patient was $419.87 (SD $129.99), the largest portion coming from ward personnel $144.47 (SD $123.30), followed by implant $134.10 (SD $15.00) medical personnel $106.86 (SD $28.18), and medications/supplies $30.05 (SD $12.28). The mean fixed cost per patient was $111.00, consisting of support staff, $103.50, and surgical instruments, $7.50.Conclusions
Our study provides empirical information on the variable and fixed costs of intramedullary nailing of femoral shaft fractures in LMICs. Importantly, the lack of surgical capacity was the primary driver of the largest cost for this procedure, preoperative ward personnel time. Our results provide the cost data for a formal cost-effectiveness analysis on this intervention.110.
Ashok Agarwal Rakesh Sharma Damayanthi Durairajanayagam Zhihong Cui Ahmet Ayaz Sajal Gupta Belinda Willard Banu Gopalan Edmund Sabanegh 《Asian journal of andrology》2016,18(1):43-53
Among infertile men, a diagnosis of unilateral varicocele is made in 90% of varicocele cases and bilateral in the remaining varicocele cases. However, there are reports of under-diagnosis of bilateral varicocele among infertile men and that its prevalence is greater than 10%. In this prospective study, we aimed to examine the differentially expressed proteins (DEP) extracted from spermatozoa cells of patients with bilateral varicocele and fertile donors. Subjects consisted of 17 men diagnosed with bilateral varicocele and 10 proven fertile men as healthy controls. Using the LTQ-orbitrap elite hybrid mass spectrometry system, proteomic analysis was done on pooled samples from 3 patients with bilateral varicocele and 5 fertile men. From these samples, 73 DEP were identified of which 58 proteins were differentially expressed, with 7 proteins unique to the bilateral varicocele group and 8 proteins to the fertile control group. Majority of the DEPs were observed to be associated with metabolic processes, stress responses, oxidoreductase activity, enzyme regulation, and immune system processes. Seven DEP were involved in sperm function such as capacitation, motility, and sperm-zona binding. Proteins TEKT3 and TCP11 were validated by Western blot analysis and may serve as potential biomarkers for bilateral varicocele. In this study, we have demonstrated for the first time the presence of DEP and identified proteins with distinct reproductive functions which are altered in infertile men with bilateral varicocele. Functional proteomic profiling provides insight into the mechanistic implications of bilateral varicocele-associated male infertility. 相似文献