A review of current studies on cellular and molecular mechanisms underlying pulmonary fibrosis induced by chemicals

Several studies showed that the inflammatory and fibrotic responses induced by polyhexamethylene guanidine phosphate (PHMG-p) were similar to those observed for idiopathic pulmonary fibrosis in South Korea in 2011. “Omic” technologies can be used to understand the mechanisms underlying chemical-induced diseases. Studies to determine the toxicity of chemicals may facilitate understanding of the mechanisms underlying the development of pulmonary fibrosis at a molecular level; thus, such studies may provide information about the toxic characteristics of various substances. In this review, we have outlined the cellular and molecular mechanisms underlying idiopathic pulmonary fibrosis and described pulmonary fibrosis induced by various chemicals, including bleomycin, paraquat, and PHMG-p, based on the results of studies performed to date.

A review of current studies on cellular and molecular mechanisms underlying pulmonary fibrosis induced by chemicals

Several studies showed that the inflammatory and fibrotic responses induced by polyhexamethylene guanidine phosphate (PHMG-p) were similar to those observed for idiopathic pulmonary fibrosis in South Korea in 2011. “Omic” technologies can be used to understand the mechanisms underlying chemical-induced diseases. Studies to determine the toxicity of chemicals may facilitate understanding of the mechanisms underlying the development of pulmonary fibrosis at a molecular level; thus, such studies may provide information about the toxic characteristics of various substances. In this review, we have outlined the cellular and molecular mechanisms underlying idiopathic pulmonary fibrosis and described pulmonary fibrosis induced by various chemicals, including bleomycin, paraquat, and PHMG-p, based on the results of studies performed to date.

Efficacy of Anterior Stromal Puncture Using 5% NaCl Eye Drops for Prolonged Time in Recurrent Corneal Erosion Syndrome

PURPOSE: The purpose of this study is to evaluate the efficacy of the combined treatment of anterior stromal puncture with the concurrent use of 5% NaCl eye drops for 6 months for recurrent corneal erosion syndrome. METHODS: A retrospective chart review was conducted for 21 patients (21 eyes) who underwent the combined treatment of anterior stromal puncture with 5% NaCl eye drops qid for 6 months to treat recurrent corneal erosion syndromes. The patients' age, gender, history of corneal trauma, history of ocular surgery, recurrence rate, need for additional treatments after recurrence and complication were analyzed. RESULTS: The mean age was 42.05 ± 13.83 years (19-68 years) with no significant difference in gender, and the mean follow up period was 8.48 ± 2.76 months (6-15 months). Among the 21 eyes 14 eyes (66.7%) had a previous history of corneal trauma, 2 eyes (9.52%) had previous refractive surgery, 1 eye (4.8%) had corneal dystrophy, 2 eyes (9.5%) had diabetic mellitus and 5 eyes (28.81%) had an unknown origin. Furthermore, 3 eyes (14.3%) developed recurrences and 2 eyes were resolved with conservative treatment while 1 eye needed additional anterior stroma puncture. There was no recurrence after retreatment with anterior stroma puncture. No significant complications such as infection or inflammation developed with the exception of corneal opacity in which one patient developed glare due to corneal opacity. CONCLUSIONS: The combined treatment of anterior stromal puncture with 5% NaCl eye drops for a prolonged time might be effective at preventing the recurrence of refractory recurrent corneal erosion syndrome with conservative treatments.

Fibroepithelial Polyp on the Eyelid Margin: A Case Report

PURPOSE: Fibroepithelial polyps on the eyelid or orbit have not been previously reported in Korea. Herein, we report our experience with a case of a primary localized fibroepithelial polyp of the eyelid. CASE SUMMARY: A 78-year-old male patient presented with a round mass on the lower eyelid which has been noticed 1 week prior. There was no pain and no tenderness. The mass was removed and excisional biopsy was performed. Histopathologic examination revealed findings suggestive of a fibroepithelial polyp. There was no local recurrence during 4 months of follow-up. CONCLUSIONS: Fibroepithelial polyp should be considered when determining the type of eyelid mass.

Appropriate In Vitro Methods for Genotoxicity Testing of Silver Nanoparticles

OBJECTIVES: We investigated the genotoxic effects of 40-59 nm silver nanoparticles (Ag-NPs) by bacterial reverse mutation assay (Ames test), in vitro comet assay and micronucleus (MN) assay. In particular, we directly compared the effect of cytochalasin B (cytoB) and rat liver homogenate (S9 mix) in the formation of MN by Ag-NPs. METHODS: Before testing, we confirmed that Ag-NPs were completely dispersed in the experimental medium by sonication (three times in 1 minute) and filtration (0.2 microm pore size filter), and then we measured their size in a zeta potential analyzer. After that the genotoxicity were measured and especially, S9 mix and with and without cytoB were compared one another in MN assay. RESULTS: Ames test using Salmonella typhimurium TA98, TA100, TA1535 and TA1537 strains revealed that Ag-NPs with or without S9 mix did not display a mutagenic effect. The genotoxicity of Ag-NPs was also evaluated in a mammalian cell system using Chinese hamster ovary cells. The results revealed that Ag-NPs stimulated DNA breakage and MN formation with or without S9 mix in a dose-dependent manner (from 0.01 microg/mL to 10 microg/mL). In particular, MN induction was affected by cytoB. CONCLUSIONS: All of our findings, with the exception of the Ames test results, indicate that Ag-NPs show genotoxic effects in mammalian cell system. In addition, present study suggests the potential error due to use of cytoB in genotoxic test of nanoparticles.

Effect of Nitric Oxide on the Change of Spinal Neuropeptide in the Inflammation Model by Freund's Complete Adjuvant / 대한해부학회지

Injection of Freund's complete adjuvant (FCA) into the plantar surface of the rat induces inflammatory responses with accompanying pain behaviors. Signs of pain behaviors observed in FCA-injected animals are reported to be similar to symptoms seen in patients with inflammatory pain. In the previous study, injection of FCA produced a significant mechanical allodynia over time. The role of substance-P and calcitonin gene-related peptide(CGRP) on allodynia induced by inflammation is still controversial. We investigated the change of spinal neuropeptides and nitric oxide (NO) in rats with inflammation induced by subcutaneous injection of FCA into hind paw. The results are: 1. The number of NADPH-diaphorase and substance P positive neurons increased at ipsilateral spinal ventral horn after FCA injection. No significant changes were found with L-NAME posttreatment. 2. Staining intensity of substance P-immunoreactive area increased at ipsilateral spinal dorsal horn after FCA injection. No significant changes were found with L-NAME posttreatment. 3. CGRP immunoreactivity changed in the same pattern with substance P in all group. The results suggest that spinal neuropeptide substance P and CGRP are involved in the mechanism of the development and maintenance of allodynia in a state of FCA-induced inflammaion. NO may be also involved in the regulation of the quantity of substance P and CGRP in spinal cord.

Effect of Nitric Oxide on Neuropeptide Y Immunoreactivity in Rat Spinal Cord on the Allodynia of Inflammation Induced by Freund's Complete Adjuvant / 대한해부학회지

Injection of Freund's complete adjuvant (FCA) into peripheral tissue induces inflammatory responses with accompanying pain behaviors. Injection of FCA produced a significant mechanical allodynia over time and nitric oxide(NO) is involved in this mechanism. The role of neuropeptide Y (NPY) on allodynia induced by inflammation is still controversal. We invastigated the change of spinal NPY and nitric oxide in rats with inflammation induced by subcutaneous injection of FCA and L-NG-nitro arginine methyl ester (L-NAME) into hind paw. The results are: The number of NADPH-diaphorase positive neurons and staining intensity of area increased at ipsilateral spinal ventral/dorsal horn of inflammation model. No significant changes were found with L-NAME posttreatment. Staining intensity of NPY immunoreactive (ir) area increased at ipsilateral spinal dorsal horn after FCA injection. No significant changes were found with L-NAME posttreatment. NPY-ir and NADPH-d reactive neurons were found in Rexed III-IV lamina at spinal dorsal horn. No significant change were found on all groups. The results suggest that spinal NPY is involved in the mechanism of the development and maintenance of allodynia in a state of FCA-induced inflammaion. NO may be also involved in the regulation of the quantity of NPY in spinal cord level.

Gender Difference of Corpus Callosum in Korean Neonate / 체질인류학회지

Corpus callosum is a co mmisural fiber connecting the cerebral hemispheres. The gender difference in the size or the shape of corpus callosum is a long standing dispute. Analysis of sexual dimorphism has been expected to provide a clue to explain sociopsychological differences. Some reported that adult female CC had more bulbous splenium and larger area considering brain size, others failed to show sexual dimorphism reported in previous studies. Only few studies were reported on sexual dimorphism of the during development. The 200 midsagittal ultrasonographs were obtained through anterior fontanelle from healthy Korean neonates (100 males, 100 females). The neonates born after 38 ~42 weeks conception were scanned and each image was analyzed with NIH image. The average area of total corpus callosum was 97.61 +/-21.05 (Mean +/-SD) mm 2 in male, 99.54 +/-20.82 mm 2 in female. Mean length of corpus callosum was 45.06 +/-4.51 mm in male, 44.46 +/-3.71 in female and mean height was 14.06 +/-1.86 mm in male, 13.4 +/-1.75 mm in female. The height of male corpus callosum was significantly higher than that of female. We could find out sexual dimorphism of spatial orientation of the corpus callosum, although there was no significant gender difference in area of corpus callosum.