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Acute kidney injury (AKI) is a major risk factor for the development of chronic kidney disease (CKD). Persistent oxidative stress and mitochondrial dysfunction are implicated across diverse forms of AKI and in the transition to CKD. In this study, we applied hyperpolarized (HP) 13C dehydroascorbate (DHA) and 13C pyruvate magnetic resonance spectroscopy (MRS) to investigate the renal redox capacity and mitochondrial pyruvate dehydrogenase (PDH) activity, respectively, in a murine model of AKI at baseline and 7 days after unilateral ischemia reperfusion injury (IRI). Compared with the contralateral sham‐operated kidneys, the kidneys subjected to IRI showed a significant decrease in the HP 13C vitamin C/(vitamin C + DHA) ratio, consistent with a decrease in redox capacity. The kidneys subjected to IRI also showed a significant decrease in the HP 13C bicarbonate/pyruvate ratio, consistent with impaired PDH activity. The IRI kidneys showed a significantly higher HP 13C lactate/pyruvate ratio at day 7 compared with baseline, although the 13C lactate/pyruvate ratio was not significantly different between the IRI and contralateral sham‐operated kidneys at day 7. Arterial spin labeling magnetic resonance imaging (MRI) demonstrated significantly reduced perfusion in the IRI kidneys. Renal tissue analysis showed corresponding increased reactive oxygen species (ROS) and reduced PDH activity in the IRI kidneys. Our results show the feasibility of HP 13C MRS for the non‐invasive assessment of oxidative stress and mitochondrial PDH activity following renal IRI.  相似文献   
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The purpose of this article is to outline the criticality of water supply in sustained operations of healthcare facilities, particularly during community emergencies, and to advocate for enhanced cross‐sector support from the water utilities in meeting this need. Information and ideas presented here were developed in the course of a regional project sponsored by the Metropolitan Washington Council of Governments (MWCOG) for development of emergency water supply operations plans for critical water uses in the Washington, DC, area.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To compare the blood flow situation in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG) using optical...  相似文献   
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Giant cell tumors of the spine are uncommon. Usually they are benign and solitary, but locally very aggressive. Most of them occur at the sacral spine. There are only 26 reported cases in the literature involving this type of tumor in the lumbar spine, in particular exhibiting an intraperitoneal growth. We present the case of a woman with a primary tumor of the lumbar spine (giant cell tumor) with intraperitoneal growth, the outcome as well as a review of the literature. Furthermore, after reviewing all spinal cases in the literature above the sacral spine, we carefully suggest a management algorithm.  相似文献   
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Background: Stress is a well-documented factor in the development of addiction. However, no longitudinal studies to date have assessed the role of stress in mediating the development of substance use disorders (SUD). Our previous results have demonstrated that a measure called Transmissible Liability Index (TLI) assessed during pre-adolescent years serves as a significant predictor of risk for substance use disorder among young adults. However, it remains unclear whether life stress mediates the relationship between TLI and SUD, or whether stress predicts SUD. Methods: We conducted a longitudinal study involving 191 male subjects to assess whether life stress mediates the relationship between TLI as assessed at age 10–12 and subsequent development of SUD at age 22, after controlling for other relevant factors. Results: Logistic regression demonstrated that the development of SUD at age 22 was associated with stress at age 19. A path analysis demonstrated that stress at age 19 significantly predicted SUD at age 22. However, stress did not mediate the relationship between the TLI assessed at age 10–12 and SUD in young adulthood. Conclusions and scientific significance: These findings confirm that stress plays a role in the development of SUD, but also shows that stress does not mediate the development of SUD. Further studies are warranted to clarify the role of stress in the etiology of SUD.  相似文献   
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