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41.
Tran Dac Phu Vu Ngoc Long Nguyen Tran Hien Phan Trong Lan Wayne Lowe Michelle S. McConnell Michael F. Iademarco Jeffrey M. Partridge James C. Kile Trang Do Patrick J. Nadol Hien Bui Diep Vu Kyle Bond David B. Nelson Lauren Anderson Kenneth V. Hunt Nicole Smith Paul Giannone John Klena Denise Beauvais Kristin Becknell Jordan W. Tappero Scott F. Dowell Peter Rzeszotarski May Chu Carl Kinkade 《MMWR. Morbidity and mortality weekly report》2014,63(4):77-80
42.
Clive M. Brown Aaron E. Aranas Gabrielle A. Benenson Gary Brunette Marty Cetron Tai-Ho Chen Nicole J. Cohen Pam Diaz Yonat Haber Christa R. Hale Kelly Holton Katrin Kohl Amanda W. Lee Gabriel J. Palumbo Kate Pearson Christina R. Phares Francisco Alvarado-Ramy Shah Roohi Lisa D. Rotz Jordan Tappero Faith M. Washburn James Watkins Nicki Pesik 《MMWR. Morbidity and mortality weekly report》2014,63(49):1163-1167
43.
Jasper G Gerbers Martin Stevens Joris JW Ploegmakers Sjoerd K Bulstra Paul C Jutte 《Acta orthopaedica》2014,85(6):663-669
Background and purpose —
In orthopedic oncology, computer-assisted surgery (CAS) can be considered an alternative to fluoroscopy and direct measurement for orientation, planning, and margin control. However, only small case series reporting specific applications have been published. We therefore describe possible applications of CAS and report preliminary results in 130 procedures.Patients and methods —
We conducted a retrospective cohort study of all oncological CAS procedures in a single institution from November 2006 to March 2013. Mean follow-up time was 32 months. We categorized and analyzed 130 procedures for clinical parameters. The categories were image-based intralesional treatment, image-based resection, image-based resection and reconstruction, and imageless resection and reconstruction.Results —
Application to intralesional treatment showed 1 inadequate curettage and 1 (other) recurrence in 63 cases. Image-based resections in 42 cases showed 40 R0 margins; 16 in 17 pelvic resections. Image-based reconstruction facilitated graft creation with a mean reconstruction accuracy of 0.9 mm in one case. Imageless CAS was helpful in resection planning and length- and joint line reconstruction for tumor prostheses.Interpretation —
CAS is a promising new development. Preliminary results show a high number of R0 resections and low short-term recurrence rates for curettage.Oncological surgical treatment can be considered to be a trade-off between margins and function, with margins being the most important factor to consider. Accuracy is needed to achieve an efficient but oncologically safe result. To assist in this, most procedures in bone tumor surgery require intraoperative imaging with fluoroscopy and/or measurements with rulers for anatomical orientation and margin control. The best examples of this are pelvic resections. Cartiaux et al. (2008) demonstrated that 4 experienced surgeons could achieve a 10-mm resection margin, with 5-mm tolerance, on pelvic sawbones in only half of the resections. The supportive imaging and measuring modalities have, however, remained more or less unchanged for many years. In a 2-dimensional (2D) workflow such as fluoroscopy, there is still the requirement for an accurate frame of reference based on anatomical landmarks for adequate 3-dimensional (3D) margin control.In recent years, the use of computer-assisted surgery (CAS) in orthopedic surgery has become more common as an alternative for intraoperative imaging and measurements, providing the necessary precision in bone tumor surgery. The technique that is mostly used in orthopedic oncology is image-based navigation. The patient’s own anatomy (MRI and/or CT) is entered into the system and used during surgery. This provides real-time, continuous, 3D imaging feedback and may lead to more precise margin control, better tissue preservation, and new approaches to reconstruction while remaining oncologically safe. Several publications have supported CAS as being a safe navigation platform for planning and performing resections (Wong et al. 2007, So et al. 2010, Cho et al. 2012). A recent publication describes lessons in the technological approach and offers comments on CAS workflow (Wong 2010). However, to date the largest case series have involved only 20 and 31 cases (Cheong and Letson 2011, Jeys et al. 2013). The reported use has mostly been limited to complex tumor resections (e.g. pelvic), and due to the novelty of the technique, applications, approaches, and set-up times differ greatly (Saidi 2012). Here we describe possible applications of CAS in bone tumor surgery (also outside of complex resections), consider their usefulness, and report preliminary results from 130 CAS procedures performed at a single institution. 相似文献44.
Marco Di Monaco Carlotta Castiglioni Fulvia Vallero Roberto Di Monaco Rosa Tappero 《Journal of bone and mineral metabolism》2014,32(5):573-579
Several factors affect the levels of parathyroid hormone (PTH) in hip-fracture patients. We hypothesized that a panel of easily assessable determinants could account for both a substantial proportion of PTH variance and the occurrence of secondary hyperparathyroidism. We evaluated 909 of 981 hip-fracture inpatients admitted consecutively to our Rehabilitation division. In each patient we assessed PTH, 25-hydroxyvitamin D, albumin-adjusted total calcium, phosphate, magnesium, and creatinine on a fasting blood sample 21.3 ± 6.1 (mean ± SD) days after fracture occurrence. Glomerular filtration rate (GFR) was estimated by the 4-variable Modification of Diet in Renal Disease Study equation. Functional level was assessed using the Barthel index. On multivariate analysis, six factors (phosphate, albumin-adjusted total calcium, estimated GFR (eGFR), 25-hydroxyvitamin D, age, and magnesium) were significantly associated with PTH levels. Overall, the panel of variables accounted for 23.7 % of PTH variance. Among the 909 patients, 304 (33.4 %) had PTH levels exceeding the normal range. Six factors (phosphate, albumin-adjusted total calcium, eGFR, 25-hydroxyvitamin D, age, and Barthel index scores) were significantly associated with the category of PTH level (either normal or elevated). The model correctly classified 70.4 % of cases. For the optimal cut-off point, sensitivity was 80 % and specificity was 61 %. Data shows that six factors were significantly associated with PTH levels in hip-fracture inpatients. However, the six factors accounted for only 23.7 % of PTH variance and the presence or absence of secondary hyperparathyroidism was correctly categorized in a modest proportion of cases. We conclude that more knowledge is needed on the factors affecting PTH levels after hip fracture. 相似文献
45.
人羊膜间充质细胞具有分化成软骨及成骨细胞的潜能 总被引:1,自引:0,他引:1
目的:人羊膜间充质细胞具有比骨髓间充质干细胞更强的扩增能力和免疫原性低等优势。建立体外适宜的诱导培养条件,观察人羊膜间充质细胞定向分化为软骨细胞和成骨细胞的能力。方法:实验于2005-09/2006-12在贵州省细胞工程重点实验室完成。①材料来源:经产妇知情同意,无菌采集健康足月分娩新生儿胎盘6份,实验经医院医学伦理委员会批准。②实验方法:采用机械法剥离羊膜组织,二步酶消化法分离收获人羊膜间充质细胞,按2.2×10~8L~(-1)密度接种,传至第1~2代用于诱导分化实验。向软骨细胞诱导分化时,人羊膜间充质细胞按3×10~8L~(-1)密度接种,诱导培养液为含体积分数0.01的胎牛血清、10 mg/L转化生长因β1、100 nmol/L地塞米松、50 mg/L抗坏血酸、1%培养基添加物。向成骨细胞诱导分化时,人羊膜间充质细胞按6×10~7L~(-1)密度接种,诱导培养液为含体积分数0.1的胎牛血清、100 nmol/L地塞米松、50 mg/L抗坏血酸、5 mmol/Lβ-甘油磷酸。③实验评估:原代细胞用流式细胞仪分析表型,免疫细胞化学染色进行波形蛋白表达鉴定。分别于体外诱导第7,14,21,28天采用免疫细胞化学法检测软骨特异性Ⅱ型胶原的表达,细胞化学法检测蛋白聚糖的表达,钙-钴法检测成骨细胞特异性碱性磷酸酶的表达,茜素红S检测钙盐沉积情况。结果:①免疫组化与表型特征:人羊膜间充质细胞高表达间充质干细胞表面标志CD29、CD44和间充质细胞标志波形蛋白。②向软骨细胞诱导分化:诱导14 d后,人羊膜间充质细胞由长梭型逐渐变为多角形,可检测到Ⅱ型胶原蛋白表达及软骨细胞特异性细胞外基质蛋白聚糖。③向成骨细胞诱导分化:诱导21 d后,可观察到人羊膜间充质细胞的胞浆内有碱性磷酸酶表达,且可见钙盐沉积。结论:人羊膜间充质细胞具有分化成软骨细胞和成骨细胞的特性,可作为骨及软骨组织工程种子细胞的新来源。 相似文献
46.
PB Greer K Dahl MA Ebert M White C Wratten P Ostwald P Pichler JW Denham 《Journal of Medical Imaging and Radiation Oncology》2008,52(5):517-524
The aims of this study were to investigate whether intrafraction prostate motion can affect the accuracy of online prostate positioning using implanted fiducial markers and to determine the effect of prostate rotations on the accuracy of the software‐predicted set‐up correction shifts. Eleven patients were treated with implanted prostate fiducial markers and online set‐up corrections. Orthogonal electronic portal images were acquired to determine couch shifts before treatment. Verification images were also acquired during treatment to assess whether intrafraction motion had occurred. A limitation of the online image registration software is that it does not allow for in‐plane prostate rotations (evident on lateral portal images) when aligning marker positions. The accuracy of couch shifts was assessed by repeating the registration measurements with separate software that incorporates full in‐plane prostate rotations. Additional treatment time required for online positioning was also measured. For the patient group, the overall postalignment systematic prostate errors were less than 1.5 mm (1 standard deviation) in all directions (range 0.2–3.9 mm). The random prostate errors ranged from 0.8 to 3.3 mm (1 standard deviation). One patient exhibited intrafraction prostate motion, resulting in a postalignment prostate set‐up error of more than 10 mm for one fraction. In 14 of 35 fractions, the postalignment prostate set‐up error was greater than 5 mm in the anterior–posterior direction for this patient. Maximum prostate rotations measured from the lateral images varied from 2° to 20° for the patients. The differences between set‐up shifts determined by the online software without in‐plane rotations to align markers, and with rotations applied, was less than 1 mm (root mean square), with a maximum difference of 4.1 mm. Intrafraction prostate motion was found to reduce the effectiveness of the online set‐up for one of the patients. A larger study is required to determine the magnitude of this problem for the patient population. The inability in the current software to incorporate in‐plane prostate rotations is a limitation that should not introduce large errors, provided that the treatment isocentre is positioned near the centre of the prostate. 相似文献
47.
48.
Alan E. Greenberg Jordan Tappero Kachit Choopanya Frits van Griensven Mike Martin Suphak Vanichseni Scott Santibanez Valerie Molotilov Shannon Hader Laura N. Broyles 《Journal of urban health》2005,82(4):iv24-iv33
The Centers for Disease Control and Prevention (CDC) has participated in collaborative HIV prevention research activities in injection drug users (IDUs) with the Bangkok Metropolitan Administration (BMA) in Bangkok, Thailand, from 1995 to the present and with the Orel AIDS Center in Orel Oblast, Russia, from 2001 to 2003. Studies in Bangkok have included an HIV prevention trial preparatory cohort from 1995 to 1998, a seroconverter cohort from 1998 to the present, a phase III trial of the AIDSVAX B/E gp 120 HIV vaccine from 1999 to 2003, and a phase II/III HIV prophylaxis trial with tenofovir scheduled to begin in 2005. Activities in Orel included a review of HIV surveillance data in 2001, focus group discussions and a case-control study with HIV-infected and-uninfected IDUs in 2001, a cross-sectional study with the female sex partners of male IDUs in 2002, and a community outreach intervention in 2002–2003. In Bangkok, 1,209 IDUs were enrolled in the preparatory cohort which revealed an HIV incidence of 5.8% per 100 person-years; 133 HIV-infected IDUs have been followed in the seroconverter cohort with >85% follow-up and HIV and tuberculosis care provided; 2,546 IDUs were enrolled in the HIV vaccine efficacy trial which was successfully completed with a followup rate of >95%, although the vaccine was not shown to be effective at reducing HIV incidence; and 1,600 IDUs will be enrolled in the daily tenofovir HIV prophylaxis trial in 2005. In Orel, initial focus group discussions and epidemiologic studies revealed low HIV knowledge and high rates of unsafe injecting and sexual practices among IDUs and their female sex partners; and educational campaigns and the community outreach intervention were developed and implemented. A steady decline in new HIV infections in IDUs was then observed in Orel in 2002–2003. CDC has participated in the conduct of successful collaborative HIV prevention research activities in Thailand and Russia over the past decade. The establishment of long-term relationships with in-country public health and community partners has been instrumental in the success of these efforts. 相似文献
49.
JW Gregory SA Greene RT Jung CM Scrimgeour MJ Rennie 《Archives of disease in childhood》1993,68(2):205-209
Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months. 相似文献
50.