Which pathologic staining method can visualize the hyperacute infarction lesion identified by diffusion MRI?: A comparative experimental study.

BACKGROUND: The study aimed to establish a staining method that could delineate the macroscopic lesion boundary of a hyperacute infarction depicted by diffusion-weighted MRI (DWI) and to validate the infarction boundary by comparing different staining methods. NEW METHOD: Thirteen rats with 1 -h middle cerebral artery (MCA) infarction were included. Five different staining methods (Hematoxylin and eosin (H&E), Nissl, 2,3,5-triphenyltetrazolium hydrochloride (TTC), microtubule associated protein 2 (MAP2), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) stains) were used to identify whether the hyperacute infarction could be histopathologically identified. Dice indices were compared to evaluate similarities in the lesion area ascertained by DWI and the staining methods. Through macroscopic lesion delineation, each region was subdivided into abnormal regions in all three stains (ROIA), abnormal in two stains (ROIB), and abnormal in only one (ROIC). Microscopic cellular changes were evaluated and graded according to each region. RESULTS: Mean Dice indices of the H&E stain were significantly higher than those of the Nissl- and MAP2-stained specimens (0.83 ±â€¯0.052, 0.58 ±â€¯0.107, and 0.56 ±â€¯0.059, respectively; p = 0.000). Grading scores for ROIs in the DWI abnormal lesions varied by region: ROIA exhibited the most severe damage [median (IQR), 3 (1)], followed respectively by ROIB [median (IQR), 2 (0)] and ROIC [median (IQR), 1 (0)] COMPARISON WITH EXISTING METHODS: H&E stain best reflects 1 h hyperacute DWI abnormal lesions. CONCLUSIONS: H&E stain allowed for the macroscopic delineation of the 1 h DWI-abnormal lesions, while MAP2 and Nissl stains could only partially depict lesions.

Retinopathy Induced by Zinc Oxide Nanoparticles in Rats Assessed by Micro-computed Tomography and Histopathology.

Nanotechnology has advanced at an extremely rapid pace over the past several years in numerous fields of research. However, the uptake of nanoparticles (NPs) into the body after administration through various routes may pose a risk to human health. In this study, we investigated the potential ocular toxicity of 20-nm, negatively- charged zinc oxide (ZnO) NPs in rats using micro-computed tomography (micro-CT) and histopathological assessment. Animals were divided into four groups as control group, ZnO NPs treatment group (500 mg/kg/day), control recovery group, and ZnO NPs treatment and recovery group. Ocular samples were prepared from animals treated for 90 days (10 males and 10 females, respectively) and from recovery animals (5 males and 5 females, respectively) sacrificed at 14 days after final treatment and were compared to age-matched control animals. Micro-CT analyses represented the deposition and distribution of foreign materials in the eyes of rats treated with ZnO NPs, whereas control animals showed no such findings. X-ray fluorescence spectrometry and energy dispersive spectrometry showed the intraocular foreign materials as zinc in treated rats, whereas control animals showed no zinc signal. Histopathological examination revealed the retinopathy in the eyes of rats treated with ZnO NPs. Neuronal nuclei expression was decreased in neurons of the ganglion cell layer of animals treated with ZnO NPs compared to the control group. Taken together, treatment with 20-nm, negatively-charged ZnO NPs increased retinopathy, associated with local distribution of them in ocular lesions.

Expression of neighbor of Punc E11 in hepatocarcinogenesis induced by diethylnitrosamine.

To identify preneoplastic markers for hepatocarcino-genesis, the expression levels of neighbor of Punc E11 (Nope), E-cadherin and α-fetoprotein (AFP) were investigated in carcinogen-treated embryonic cell lineages. Mouse embryonic stem cells (ESCs), hepatic progenitor cells (HPCs), and hepatocyte­like cells (HCs) representing 0, 22, and 40 days of liver differentiation, respectively, were treated in vitro with diethylnitrosamine (DEN) at 4 doses (0, 1, 5, and 15 mM) for 24 h. The expression of Nope, E-cadherin and AFP was examined by quantitative real-time PCR, western blotting and immunocytochemistry. DEN treatment significantly increased the mRNA expression of Nope in ESCs and HPCs, and that of E-cadherin and AFP in all three cell lines, although the changes in expression were triggered by varying DEN concentrations. Immunofluorescence staining revealed that Nope was expressed at the cell membrane in ESCs and HPCs and within granules or in the cytoplasm of HCs, which was also stained by E-cadherin. DEN treatment induced Nope expression in ESCs, HPCs and HCs and caused a concomitant increase in E-cadherin expression. Although Nope expression clearly increased following tumor induction, its expression pattern changed with the developmental stage. In conclusion, we determined that Nope expression may carry prognostic significance during early hepatocarcinogenesis. Moreover, Nope expression may serve as a novel oncofetal surface marker for preneoplastic stages that are not identifiable by the commonly used marker, AFP.

Ratio of angiopoietin-2 to angiopoietin-1 predicts mortality in acute lung injury induced by paraquat.

BACKGROUND: To determine whether initial reactive oxygen species (ROS)-induced endothelial cell injury is involved in early death after paraquat intoxication and concentrations of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), and von Willebrand factor (VWF) reflecting endothelial cell injury, we investigated the initial endothelial cell injury marker involved in the pathogenesis of death within 5 days after paraquat ingestion. MATERIAL/METHODS: Sixty patients with paraquat poisoning were prospectively enrolled. Plasma samples were collected at admission. Plasma concentrations of Ang-1, Ang-2, and VWF were measured by enzyme-linked immunosorbent assay. The patients were classified into 3 categories: survivors, early death (died within 5 days after ingestion), and late death (died more than 5 days after ingestion). RESULTS: The baseline concentration of Ang-2 and the Ang-2: Ang-1 ratio were significantly higher in patients who died (Ang-2 [pg/mL], 1012.75 ± 468.02 vs. 1986.07 ± 1675.37 [p=0.002]; Ang-2: Ang-1, 0.90 ± 0.49 vs. 2.16 ± 2.28 [p=0.002]). The Ang-2: Ang-1 ratio was significantly higher in the early death group (2.41 ± 2.54) than in the survivors (0.90 ± 0.49) and the late death group (1.33 ± 0.64). The Ang-2: Ang-1 ratio was significantly associated with early death (OR, 2.602; 95% CI, 1.106-6.117; p=0.028) after adjusting for plasma levels of paraquat, age, PCO2, and creatinine. VWF did not predict mortality. CONCLUSIONS: Endothelial cell damage could be involved in the pathogenesis of early death following paraquat ingestion.