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961.
PurposeTo explore the changes in T2-weighted (T2w) and apparent diffusion coefficient (ADC) magnetic resonance imaging -derived radiomic features of the gross tumor volume (GTV) from focal salvage high-dose-rate prostate brachytherapy (HDRB) and to correlate with clinical parameters.Materials and MethodsEligible patients included those with biopsy-confirmed local recurrence that correlated with MRI (T2w, ADC). Patients received 27 Gy in 2 fractions separated by 1 week to a quadrant consisting of the GTV. The MRI was repeated 1 year after HDRB. GTVs, planning target volumes, and normal prostate tissue control volumes were identified on the pre- and post-HDRB MRIs. Radiomic features from each GTV were extracted, and principle component analysis identified features with the highest variance.ResultsPre- and post-HDRB MRIs were obtained from 14 trial patients. Principle component analysis showed that 18 and 17 features contributed to 93% and 86% of the variance observed in the T2w and ADC data, respectively. Sixteen T2w features and 1 ADC GTV feature were different from the control volumes in the pre-HDRB images (p < 0.05). Ten T2w and 7 ADC GTV post-HDRB features were different from those of pre-HDRB (p < 0.05).ConclusionsExploratory analysis reveals several radiomic features in the T2w and ADC image GTVs that distinguish the GTV from healthy prostate tissue and change significantly after salvage HDRB.  相似文献   
962.
963.
Islet xenotransplantation represents an attractive solution to overcome the shortage of human islets for use in type 1 diabetes. The wide‐scale application of clinical islet xenotransplantation, however, requires that such a procedure takes place in a specifically and tightly regulated environment. With a view to promoting the safe application of clinical islet xenotransplantation, a few years ago the International Xenotransplantation Association (IXA) published a Consensus Statement that outlined the key ethical and regulatory requirements to be satisfied before the initiation of xenotransplantation studies in diabetic patients. This earlier IXA Statement also documented a disparate regulatory landscape among different geographical areas. This situation clearly fell short of the 2004 World Health Assembly Resolution WHA57.18 that urged Member States “to cooperate in the formulation of recommendations and guidelines to harmonize global practices” to ensure the highest ethical and regulatory standards on a global scale. In this new IXA report, IXA members who are active in xenotransplantation research in their respective geographic areas herewith briefly describe changes in the regulatory frameworks that have taken place in the intervening period in the various geographic areas or countries. The key reassuring take‐home message of the present report is that many countries have embraced the encouragement of the WHO to harmonize the procedures in a more global scale. Indeed, important regulatory changes have taken place or are in progress in several geographic areas that include Europe, Korea, Japan, and China. Such significant regulatory changes encompass the most diverse facets of the clinical application of xenotransplantation and comprise ethical aspects, source animals and product specifications, study supervision, sample archiving, patient follow‐up and even insurance coverage in some legislations. All these measures are expected to provide a better care and protection of recipients of xenotransplants but also a higher safety profile to xenotransplantation procedures with an ultimate net gain in terms of international public health.  相似文献   
964.
In 2009, the International Xenotransplantation Association (IXA) published a consensus document that provided guidelines and “recommendations” (not regulations) for those contemplating clinical trials of porcine islet transplantation. These guidelines included the IXA's opinion on what constituted “rigorous pre‐clinical studies using the most relevant animal models” and were based on “non‐human primate testing.” We now report our discussion following a careful review of the 2009 guidelines as they relate to pre‐clinical testing. In summary, we do not believe there is a need to greatly modify the conclusions and recommendations of the original consensus document. Pre‐clinical studies should be sufficiently rigorous to provide optimism that a clinical trial is likely to be safe and has a realistic chance of success, but need not be so demanding that success might only be achieved by very prolonged experimentation, as this would not be in the interests of patients whose quality of life might benefit immensely from a successful islet xenotransplant. We believe these guidelines will be of benefit to both investigators planning a clinical trial and to institutions and regulatory authorities considering a proposal for a clinical trial. In addition, we suggest consideration should be given to establishing an IXA Clinical Trial Advisory Committee that would be available to advise (but not regulate) researchers considering initiating a clinical trial of xenotransplantation.  相似文献   
965.
We established the timing of peak bone mass acquisition and body composition maturation and provide an age- and sex-specific body composition and bone density reference database using dual-energy X-ray absorptiometry in Korean subjects 10–25 years of age. Reference percentiles and curves were developed for bone mineral content (BMC), bone mineral density (BMD) of the whole body, the lumbar spine, and the femoral neck, and for fat mass (FM) and lean mass (LM) of 1969 healthy participants (982 males) who participated in the 2009–2010 Korean National Health and Nutrition Examination Survey. Additionally, bone mineral apparent density (BMAD), FM index, and LM index were calculated to adjust for body size. BMC and BMD at all skeletal sites as well as LM increased with age, reaching plateaus at 17–20 years of age in females and 20–23 years of age in males. The femoral neck was the first to reach a bone mass plateau, followed by the lumbar spine and then the whole body. Spine BMAD increased with age in both sexes, but femoral and whole-body BMAD remained the same over time. Females displayed a dramatic increase in FM during puberty, but the FM of males decreased until mid-puberty. These findings indicate that bone health and body composition should be monitored using a normal reference database until the late second to early third decade of life, when statural growth and somatic maturation are completed.  相似文献   
966.

Background

Recent national infection control efforts have been directed at reducing postsurgical infection rates, related morbidity, and cost. We sought to evaluate population-level rates of deep sternal wound infection (DSWI) after cardiac surgery, associated mortality, and resource use compared to patients undergoing cardiac surgery without postoperative DSWI relative to historical trends.

Methods

We analyzed the MarketScan ® Commercial Claims Databases from 2009 to 2013 to identify adult patients who developed DSWI after open cardiac surgery. Patients with and without DSWI were compared. The outcomes of interest included 30-day, 90-day, and 1-year in-hospital mortality. Utilization outcomes, including total hospital days and inpatient costs, were calculated in the time period from the index cardiac surgery through 90 days after DSWI diagnosis.

Results

In this cohort, 176,537 patients underwent one or more cardiac surgery procedures. DSWI occurred in 2835 (1.6 %) patients. One-year mortality for patients with DSWI was 10.7 versus 2.5 % (P < 0.001) in patients without DSWI. Mean hospital days in patients with DSWI were 33 versus 9 days for patients without DSWI (P < 0.001). Mean cost for patients with DSWI was greater than 2.5 times that of patients without DSWI ($211,478 vs $82,089, P < 0.001).

Conclusions

Treatment of DSWI results in substantial morbidity, mortality, and excess cost for treating facilities. The rates of DSWI have not decreased dramatically over the last 10–20 years. Thus, more attention needs to be focused toward understanding treatment variation that exists in patients diagnosed with DSWI.
  相似文献   
967.

Purpose

We estimated the annual changes in radiographic indices of the spine in cerebral palsy (CP) patients and analyzed the factors that influence its progression rate.

Methods

We included CP patients who had undergone whole-spine radiography more than twice and were followed for at least 1 year. The scoliosis Cobb angle, coronal balance, apical vertebral translation, apical rotation, and pelvic obliquity were measured on anteroposterior (AP) radiographs; thoracic kyphosis and lumbar lordosis angles, and sagittal balance was measured on lateral radiographs; and migration percentage was measured on AP hip radiographs to determine hip instability. For each gross motor function classification system (GMFCS) level, the Cobb angles, apical vertebral translation, coronal and sagittal balance, and pelvic obliquity were adjusted by multiple factors with a linear mixed model.

Results

A total of 184 patients (774 radiographs) were included in this study. There was no significant annual change in scoliosis Cobb, thoracic kyphosis, and lumbar lordosis angles in the GMFCS level I–II and III groups. In the GMFCS level IV–V group, there was an annual increase of 3.4° in the scoliosis Cobb angle (p = 0.020). The thoracic kyphosis angle increased by 2.2° (p = 0.018) annually in the GMFCS level IV–V group. Apical vertebral translation increased by 5.4 mm (p = 0.029) annually in the GMFCS level IV–V group. Progression of coronal and sagittal balance and pelvic obliquity with aging were not statistically significant. Sex, hip instability, hip surgery, and triradiate cartilage did not affect the progression of scoliosis and the balance of the spine and pelvis.

Conclusions

The scoliosis Cobb angle, thoracic kyphosis angle, and apical vertebral translation in the GMFCS level IV–V CP patients progressed with age. These findings can predict radiographic progression of scoliosis in CP patients.
  相似文献   
968.
Kim  Chi Heon  Chung  Chun Kee  Lee  Sun-Ho  Jahng  Tae-Ahn  Hyun  Seung-Jae  Kim  Ki-Jeong  Yoon  Sang Hoon  Kim  Eun-Sang  Eoh  Whan  Kim  Hyun-Jib  Kim  Kyoung-Tae  Sung  Joo-Kyung  Choi  Yunhee 《European spine journal》2016,25(12):4025-4032
Purpose

Simpson grade II removal (coagulation of the dural attachment after gross total removal) of spinal meningioma is considered an acceptable alternative, but increased recurrence after more than 10 years has been reported. More attention must be paid to the long-term surgical outcomes after Simpson grade II removal.

Methods

A retrospective review was performed for 20 patients (M:F = 5:15; age, 59 ± 9 years) with Simpson grade II removal (mean follow-up period, 12.9 years; range 10.0–17.5). Magnetic resonance (MR) imaging was conducted in 17 patients at 88 ± 52 months (range 12–157). During the same period, Simpson grade I removal (removal of the dural origin) was performed in 21 patients (follow-up, 89 ± 87 months; range 9–316). Radiological recurrence was defined as a visible tumor on a follow-up MR image, and clinical tumor recurrence was defined as the recurrence of symptoms.

Results

At the final follow-up, neurological symptoms had improved in 16/20 patients and remained stable in 4/20. A recurrent tumor was detected in one patient due to increased back pain at 92 months postoperative, but the symptom was stable without surgery until the last follow-up (124 months). The radiological and clinical recurrence-free survival periods were 150 ± 7 months (95 % CI 136–163) and 204 ± 6 months (95 % CI 193–215), respectively. There was no recurrence after Simpson grade I removal, whereas neurological deterioration occurred in two patients after surgery.

Conclusions

Simpson grade II removal may be an alternative option if the risk of complications with Simpson grade I removal is expected to be high.

  相似文献   
969.

Purpose

Although ependymomas occur in both the brain and the spine, the prognosis is quite varied by tumor location. Spinal ependymomas usually follow a relatively benign course with more favorable prognosis than that of the intracranial ependymomas. The aim of this study is to evaluate the genetic differences between spinal ependymomas and their intracranial counterparts using a meta-analysis.

Methods

We searched PubMed, Embase, Web of Science, and the Cochrane library. Comparative or single arm genetic studies that enrolled patients with both intracranial and spinal ependymoma were included. The frequency of genetic aberration was calculated in each group. We calculated the odds ratio (OR) with 95 % confidence intervals (CIs) for direct comparative studies and the logit event rate (LER) and 95 % CI for single arm studies.

Results

Twenty-five studies comprising of 380 spinal ependymomas and 964 intracranial ependymomas were compared to determine the association of the genetic differences of ependymomas at different locations. There were 25 comparable genetic aberrations between spinal and intracranial ependymomas. Among the genes, the NF2 mutation was significantly associated with the spinal ependymomas rather than with the intracranial ependymomas (spinal tumor: LER ?0.750, 95 % CI ?1.233 to ?0.266, intracranial tumor: LER ?3.080, 95 % CI ?3.983 to ?2.177). Intracranial ependymomas were found to be significantly associated with EPB41L3 deletion (OR 0.34; 95 % CI 0.14–0.80) and HIC1 methylation (OR 0.12; 95 % CI 0.02–0.68).

Conclusion

The genetic aberrations of spinal ependymomas are quite different from those of intracranial ependymomas. The difference in prognosis of ependymoma by location may be associated with genetic difference. A more detailed understanding of them may enable the development of targeted therapy and the estimation of prognosis.
  相似文献   
970.
This study was conducted to investigate the effect of black cohosh (BC) extract on the proliferation and apoptosis of Ishikawa cells. Ishikawa human endometrial adenocarcinoma cells were treated with or without BC (1, 5, 10 and 25?μM) and cell proliferation and cytotoxicity were measured by CCK-8 assays and flow cytometry analysis. Additionally, Ishikawa cells were treated with 17β-estradiol (E2), E2?+?progesterone and E2?+?BC (5 and 10?μM) and the effect of BC and progesterone on E2-induced cell proliferation was analyzed. BC decreased the proliferation of Ishikawa cells at a dose-dependent rate compared with the control group (p?p?相似文献   
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