A molecularly cloned human cellular H-ras (c-H-ras) oncogene(pbc N1 plasmid) was treated with N-acetoxyacetylaminofluorene (AAAF) in vitro and subcloned into E.coli. This was done to identify the mutational changes at specific codons of the gene. Guanine nucleotides were identified as the major AAAF binding site of the DNA adduct formed. Base changes in codons 12 and 61 were determined by the analysis of restriction fragment length polymorphism (RFLP) and site specific oligonucleotide hybridization. RFLP was observed due to the loss of the Hpall recognition site at codon 11 and 12 of AAAF-treated c-H-ras gene. Hybridization of AAAF treated c-H-ras with 32P-labeled oligonucleotide probes for the mutant alleles of codon 61 showed no substitutions at codon 61. From these results, it is assumed that AAAF treatment in vitro caused mutation at codon 12 but not at codon 61 of the c-H-ras oncogene and that codon 12 is the primary target of mutation by AAAF
Acetoxyacetylaminofluorene/*pharmacology ; Chromatography, Thin Layer ; Codon ; *DNA Damage ; Electrophoresis, Agar Gel ; Genes, ras/*drug effects/genetics ; Human ; Mutagenesis, Site-Directed ; Oligonucleotide Probes ; Plasmids/drug effects/genetics ; Polymorphism, Restriction Fragment Length

Background: This study aimed to establish a strategy to improve the poor working environment and working conditions among long-term healthcare workers in Korea. Methods: A total of 600 questionnaires with which long-term health care workers participated in the targeted base areas of each city and province nationwide were distributed directly and 525 responses were collected and 506 responses were analyzed. Surveys, on-site field visits, and in-depth interviews were also conducted to understand the working environment as well as conditions and establish a strategy for improving the working environment among long-term healthcare workers to understand the demands of working conditions and working conditions. Results: Korean long-term care workers firstly and mostly enumerated their risk factors for ill-health when lifting or moving elderly recipients directly by hand (69.9%), followed by increased physical workload with old beds, tools, and facilities (42.3%) in the workplaces, shortage of manpower (32%), and source of infection (30%). To improve the working environment as well as conditions, Korean long-term care workers considered improving low-wage structures, ergonomic improvements to solve excessive physical loads, and increasing various bonus payments as well as implementing the salary system, positive social awareness, and increasing resting time. Of 506 responses, 92.3% replied that the long-term care insurance system for the elderly should be developed to expand publicization at the national level. Conclusion This study proposes to improve the low-wage structure of Korean long-term care workers, automation and improvement of facilities, equipment, and tools to eliminate excessive physical loads (beneficiary elderly lifting), and reduction of night labor.

PURPOSE: To determine which magnetic resonance (MR) imaging sequence demonstrates the highest lesion conspicuity for lesion detection in neonates with hypoxic-ischemic encephalopathy (HIE). MATERIALS AND METHODS: In 30 neonates with HIE, lesion conspicuity in different brain structures was retrospectively compared on T1-weighted images, T2-weighted images, fluid-attenuated inversion recovery images, and diffusion-weighted images (DWI). The brain structures were categorized as follows: cerebral cortex; cerebral white matter; deep gray matter; posterior limb of the internal capsule (PLIC); brain stem; and cerebellum. RESULTS: For the deep gray matter, T1-weighted imaging was superior to the other sequences in lesion detection of 9 of 14 patients (64.3%), whereas DWI was superior in only 4/14 patients (28.6%). For the cerebral cortex, T1- and DWI were similar in lesion conspicuity (5/13 patients and 6/13 patients, respectively). For the white matter, HIE lesions were most conspicuous on DWI in a majority of the study patients. Lesions were detected in the cerebral white matter in 16/20 patients (80.0%), lesions were detected in the PLIC in 11/12 patients (91.7%), lesions were detected in the corticospinal tract in the brain stem in 11/11 patients (100%) and lesions were detected in the cerebellar white matter in one patient (100%). CONCLUSION: In neonates with HIE, white matter lesions are most conspicuous on DWI, whereas gray matter lesions tend to have greater conspicuity on T1-weighted images than on the other MR sequences.
Brain ; Brain Stem ; Cerebral Cortex ; European Continental Ancestry Group ; Extremities ; Humans ; Hypoxia-Ischemia, Brain ; Infant, Newborn ; Internal Capsule ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Magnetics ; Magnets ; Pyramidal Tracts ; Retrospective Studies

PURPOSE: To evaluate the protective effect of applying an ophthalmic viscosurgical device (OVD) to the ocular surface during cataract surgery and its ability to prevent dry eye syndrome. METHODS: Twenty-four patients aged 50 to 75 years who underwent cataract surgery at Seoul National University Bundang Hospital and agreed to participate in the study were included and divided into two groups: a study group who underwent cataract surgery after application of an OVD to the ocular surface, and a control group who underwent cataract surgery without application of an OVD. DisCoVisc was used as the OVD in the study group, while other factors including surgical techniques and administration of anesthetic agents were performed in both groups in the same manner. Indicators of dry eye syndrome including ocular staining score, tear break-up time, and tear osmolality were analyzed. Ocular surface disease index and a visual analog scale were analyzed for dry eye symptoms, and the amount of balanced salt solution used during surface irrigation and operation time were also analyzed. RESULTS: Significant improvement in the tear break-up time, corneal ocular staining score, and ocular surface disease index score in the study group compared with the control group one week after operation (by the Mann-Whitney test). Use of OVD was associated with longer operating time. CONCLUSIONS: OVD applied to the ocular surface during cataract surgery had a protective effect on the ocular surface one week after surgery.
Anesthetics ; Cataract Extraction ; Cataract ; Dry Eye Syndromes ; Humans ; Osmolar Concentration ; Seoul ; Tears ; Visual Analog Scale