Z-Ligustilide inhibits benzo(a)pyrene-induced CYP1A1 upregulation in cultured human keratinocytes via ROS-dependent Nrf2 activation.

Benzo(a)pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH), is an environmental contaminant that can induce cytochrome P4501A1 (CYP1A1) upregulation via aryl hydrocarbon receptor (AhR) activation and provoke inflammation. Here, we investigated the effect of Z-Ligustilide, an active ingredient isolated from the medicinal plants Cnidium officinale and Angelica acutiloba, on BaP-induced CYP1A1 upregulation in normal human epidermal keratinocytes (NHEKs) as well as its underlying mechanisms. Z-Ligustilide significantly inhibited BaP-induced CYP1A1 upregulation in NHEKs. Treatment of NHEKs with Z-Ligustilide induced Nuclear factor-E2-related factor 2 (Nrf2) nuclear translocation and expression of the Nrf2-regulated genes for haeme oxygenase-1 (HO-1) and NAD(P)H: quinine oxidoreductase-1 (NQO1). AhR silencing, SB203580 (a p38 inhibitor), SP600125 (a JNK inhibitor), U0126 (a MEK inhibitor) and LY294002 (a PI3K inhibitor) did not suppress Z-Ligustilide-induced Nrf2 activation. Moreover, treatment of NHEKs with Z-Ligustilide increased reactive oxygen species (ROS) and L-N-acetylcysteine (L-NAC, an antioxidant) attenuated Z-ligustilide-induced Nrf2 nuclear translocation and HO-1 expression. L-NAC or knock-down of Nrf2 significantly attenuated the inhibitory effects of Z-Ligustilide on BaP-induced CYP1A1 upregulation in NHEKs. Taken together, these findings suggest that Z-Ligustilide can suppress BaP-induced CYP1A1 upregulation through ROS-dependent Nrf2 pathway activation and may be beneficial in preventing or treating BaP-induced skin damage.

Improved delineation of the anterior spinal artery with model-based iterative reconstruction in CT angiography: a clinical pilot study.

OBJECTIVE: The purpose of this study was to investigate the utility of model-based iterative reconstruction (MBIR) for improving delineation of the anterior spinal artery (ASA) during routine-dose CT angiography. MATERIALS AND METHODS: For imaging of 10 patients (six men, four women; mean age, 73.9 ± 7.5 years) consecutively undergoing CT angiography of the whole aorta with a 12-HU noise index, we used filtered back projection with a standard kernel, adaptive statistical iterative reconstruction of 40% with a detail kernel, and MBIR to reconstruct axial and oblique coronal multiplanar reformation images to delineate the ASA. We measured objective noise in the spinal cord and contrast-to-noise ratio (CNR) between the aorta and spinal cord on axial images at the T12 level. Two radiologists independently graded subjective noise and ASA delineation on the multiplanar reformation images from 1 (poor) to 4 (excellent). We compared results among the three reconstructions using one-way analysis of variance and Tukey-Kramer significance tests. RESULTS: Objective noise, CNR, and subjective image noise and ASA delineation improved significantly with MBIR. Image noise was 18.4 ± 3.6 HU and CNR, 23.4 ± 8.6 (reader 1 scores, 3.9 ± 0.3 and 3.7 ± 0.5; reader 2, 3.9 ± 0.3 and 3.5 ± 0.7). With filtered back projection, image noise was 34.7 ± 8.3 HU and CNR 12.1 ± 4.0 (reader 1 scores, 2.0 ± 0.0 and 2.2 ± 0.4; reader 2, 2.2 ± 0.4 and 2.5 ± 0.7), and with ASIR, 33.0 ± 8.1 HU and 12.7 ± 4.3 (reader 1 scores, 2.0 ± 0.0 and 2.2 ± 0.4; reader 2, 2.2 ± 0.4 and 2.5 ± 0.7) (p < 0.05). Results between filtered back projection and adaptive statistical iterative reconstruction were comparable. CONCLUSION: Use of MBIR can improve delineation of the ASA during CT angiography.

Detection of paranasal sinus opacification with digital tomosynthesis radiography: a clinical pilot study.

OBJECTIVE: We investigated the diagnostic accuracy of digital tomosynthesis (DT) radiography for detecting sinus opacification. METHODS: For 31 adult patients with signs suggestive of sinusitis who underwent both sinus multi-detector-row computed tomography and DT, 2 readers independently assessed opacification in the maxillary, ethmoid, frontal, and sphenoid sinuses by DT and in consensus determined the presence of opacification in each sinus by multi-detector-row computed tomography as a reference. We assessed the diagnostic accuracy of DT and interreader agreement with DT using Cohen κ statistics. RESULTS: For the maxillary, ethmoid, frontal, and sphenoid sinuses, opacification was identified in 81.7%, 75.9%, 59.3%, and 40.7%; the sensitivity/specificity for detecting opacification by DT were 93.9/72.7%, 79.5/71.4%, 93.8/72.7%, and 90.9/75.0% for reader 1 and 95.9/100.0%, 95.5/92.9%, 100.0/81.8%, and 81.8/75.0% for reader 2; the interreader agreement was 0.79, 0.42, 0.67, and 0.63, respectively. CONCLUSIONS: Digital tomosynthesis allows relatively accurate detection of sinus opacification with substantial interreader agreement for all the sinuses except the ethmoid sinuses.