Plos One
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Chronic inflammation and subsequent fibrosis induced by mechanical stress play an important role in ligamentum flavum (LF) hypertrophy and degeneration in patients with lumbar spinal canal stenosis (LSCS). Angiopoietin-like protein 2 (Angptl2) is a chronic inflammatory mediator induced under various pathological conditions and increases the expression of TGF-β1, which is a well-characterized mediator in LF hypertrophy. We investigated whether Angptl2 is induced by mechanical stress, and whether it contributes to LF hypertrophy and degeneration by activating the TGF-β1 signaling cascade. ⋯ In vitro experiments revealed that Angptl2 increased levels of TGF-β1 and its receptors, and also activated TGF-β1/Smad signaling. Mechanical stretching stress increased TGF-β1 mRNA expression, which was partially attenuated by treatment with a calcineurin/NFAT inhibitor or Angptl2 siRNA, indicating that induction of TGF-β1 expression by mechanical stretching stress is partially mediated by Angptl2. We conclude that expression of Angptl2 induced by mechanical stress in LF fibroblasts promotes LF tissue degeneration by activation of TGF-β1/Smad signaling, which results in LF hypertrophy in patients with LSCS.
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Because of the limitations of existing methods and techniques for directly obtaining real-time blood data, no accurate microflow in vivo real-time analysis method exists. To establish a novel technical platform for real-time in vivo detection and to analyze average blood pressure and other blood flow parameters, a small, accurate, flexible, and nontoxic Fabry-Perot fiber sensor was designed. The carotid sheath was implanted through intubation of the rabbit carotid artery (n = 8), and the blood pressure and other detection data were determined directly through the veins. ⋯ The average ambulatory blood pressure measured by the fiber sensor exhibited a negative correlation with the quantity of blood platelets (correlation coefficient of -0.839, P<0.05). The novel fiber sensor can thus obtain in vivo blood pressure data accurately, stably, and in real time; the sensor can also determine the content and status of the blood flow to some extent. Therefore, the fiber sensor can obtain partially real-time vascular rheology information and may thus enable the early diagnosis of blood rheology disorders and diseases.
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Few studies have been conducted specifically on the dense connective tissue located in the posterior medial part of the cervical epidural space. This study was undertaken to examine the presence of this connection between the cervical dura mater and the posterior wall of spinal canal at the level of C1-C2. 30 head-neck specimens of Chinese adults were used. Gross dissection was performed on the suboccipital regions of the 20 specimens. ⋯ These two structures, TBNL and VDL, firmly link the posterior aspect of cervical dura mater to the rear of the atlas-axis and the nuchal region. According to these findings, the authors speculated that the movements of the head and neck are likely to affect the shape of the cervical dural sleeve via the TBNL and VDL. It is hypothesized that the muscles directly associated with the cervical dural sleeve, in the suboccipital region, may work as a pump providing an important force required to move the CSF in the spinal canal.
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Before using any prediction rule oriented towards pulmonary embolism (PE), family physicians (FPs) should have some suspicion of this diagnosis. The diagnostic reasoning process leading to the suspicion of PE is not well described in primary care. ⋯ This study illustrated the diagnostic role of gut feelings in the specific context of suspected pulmonary embolism in primary care. The FPs used the sense of alarm as a tool to prevent the diagnostic error of missing a PE. The diagnostic accuracy of gut feelings has yet to be evaluated.
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To evaluate the utilization trends of advanced radiology, i.e. computed tomography (CT) and magnetic resonance imaging (MRI), examination in an emergency department (ED) of an academic medical center from 2001 to 2010. ⋯ We report a three-fold and nine-fold increase in the use of CT and MRI, respectively, during the study period. Additional studies will be required to understand the causes of this change and to determine the effect of advanced radiology utilization on the patient outcome.