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991.
Bmi1, stem cells, and senescence regulation   总被引:18,自引:0,他引:18       下载免费PDF全文
Stem cells generate the differentiated cell types within many organs throughout the lifespan of an organism and are thus ultimately responsible for the longevity of multicellular organisms. Therefore, senescence of stem cells must be prevented. Bmi1 is required for the maintenance of adult stem cells in some tissues partly because it represses genes that induce cellular senescence and cell death.  相似文献   
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Background

Adjacent segment disease (ASDz) is a potential complication following lumbar spinal fusion. A common nomenclature based on etiology and ASDz type does not exist and is needed to assist with clinical prognostication, decision making, and management.

Questions/Purposes

The objective of this study was to develop an etiology-based classification system for ASDz following lumbar fusion.

Methods

We conducted a retrospective chart review of 65 consecutive patients who had undergone both a lumbar fusion performed by a single surgeon and a subsequent procedure for ASDz. We established an etiology-based classification system for lumbar ASDz with the following six categories: “degenerative” (degenerative disc disease or spondylosis), “neurologic” (disc herniation, stenosis), “instability” (spondylolisthesis, rotatory subluxation), “deformity” (scoliosis, kyphosis), “complex” (fracture, infection), or “combined.” Based on this scheme, we determined the rate of ASDz in each etiologic category.

Results

Of the 65 patients, 27 (41.5%) underwent surgery for neurogenic claudication or radiculopathy for adjacent-level stenosis or disc herniation and were classified as “neurologic.” Ten patients (15.4%) had progressive degenerative disc pathology at the adjacent level and were classified as “degenerative.” Ten patients (15.4%) had spondylolisthesis or instability and were classified as “instability,” and three patients (4.6%) required revision surgery for adjacent-level kyphosis or scoliosis and were classified as “deformity.” Fifteen patients (23.1%) had multiple diagnoses that included a combination of categories and were classified as “combined.”

Conclusion

This is the first study to propose an etiology-based classification scheme of ASDz following lumbar spine fusion. This simple classification system may allow for the grouping and standardization of patients with similar pathologies and thus for more specific pre-operative diagnoses, personalized treatments, and improved outcome analyses.

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The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is overwhelming healthcare resources and infrastructure worldwide. Earlier reports have demonstrated complicated postoperative courses and high fatality rates in patients undergoing emergent cardiothoracic surgery who were diagnosed postoperatively with COVID-19. These reports raise the possibility that active COVID-19 might precipitate a catastrophic pathophysiological response to infection in the postoperative period and lead to unfavorable surgical outcomes. Hence, it is imperative to screen patients with SARS-CoV-2 infection before surgery and to carefully monitor them in the postoperative period to identify any signs of active COVID-19. In this report, we present the successful outcome of coronary artery bypass grafting (CABG) operation in a patient with asymptomatic SARS-CoV-2 infection presenting with an acute coronary syndrome and requiring urgent surgical intervention. We employed a thorough strategy to identify subclinical COVID-19 disease, and after confirming the absence of active disease, proceeded with the CABG operation. The patient outcome was successful with the absence of any overt COVID-19 manifestations in the postoperative period.  相似文献   
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