• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.511-518
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• 1998

In order to develop the aerosol bolus technique which is thought to be a potential tool for probing geometries or abnormalities of small airways, an experimental system of measuring fast time variations of particle concentration in the inhaled and exhaled breathing air was developed. The system generates monodisperse sebacic acrid particles of 1 micron size and 1.2 of geometric standard deviation in high concentration of $10^8$ particles/cc, delivers a short pulse of particles at the controlled instant during inhalation using a solenoid valve, and measures the fast change of particle concentration in using the laser light scattering. Successful operation of the generator and the measuring system was confirmed by smooth concentration profiles in inhalation. It was also confirmed that maintaining a constant breathing rate is essential to stable outputs and any disturbance in flow rate near the mode (maximum concentration) induces a large number of spurious peaks in the exhalation. Experimental data without strict control of breathing flow rate showed a substantial amount of scatter. The measured results showed an improvement in scatter over the existing results. When compared with theoretical predictions from 1-D convective diffusion equation and other experiments, general characteristics of dispersion for several penetration depths showed a good agreement, but there exists some difference in absolute values, which is attributed to the difference in body conditions. Improvements are needed in the theory, especially in relation to correcting for the effect of breathing flow rate.

• Advances in pediatric surgery
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• v.15 no.1
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• pp.1-10
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• 2009

Recently, amniotic fluid has gained attention as one of the potential sources for cell therapy and tissue engineering because it has characteristics of multipotent stem cells. However, current knowledge about what types of cells are naturally found in amniotic fluid is still limited. In this study, we aimed to investigate whether human amniotic fluid contains cells that have characteristics of respiratory cells. Samples of human amniotic fluid (5 mL per sample) obtained from amniocenteses were cultured with small airway growth medium (SAGM). Cells were grown until the third passage and the presence of type II alveolar cells were characterized by inverted microscopy, immunofluorescence, and reverse transcription polymerase chain reaction (RT-PCR). On inverted microscopy, cultured cells showed typical polygonal and cobblestone-like epithelial morphology. The morphology of cells was not changed after selection and passing. Immunofluorescence analysis demonstrated that the isolated cells stained positive for surfactant protein C (SPC), specific marker for type II alveolar cells. Cells also stained positive for TTF-1 protein but negative for CD 31 and vimentin. RT-PCR analysis of cells showed expression of SPC mRNA. This study has demonstrated that respiratory cells can be isolated and identified from human amniotic fluid cultured in SAGM medium. Our results may provide the basis for further investigations of amniotic fluid.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.655-664
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• 1995

Sixty male patients with polysomnographically documented OSA were included in this study. A pair of cephalograms were obtained in the upright and supine positions. In the supine position, the ANB angle, lower facial height and the cross-sectional area of soft palate increased and there was a decrease in the vertical airway length and oropharynx cross-sectional area. Positional changes did not affect the cross-sectional area of tongue, but the cross-sectional area of the oropharynx decreased in the supine position. The obese group had higher AI and RDI. Maxillary unit length, C3-H, the cross-sectional areas of tongue, soft palate and oropharynx were significantly greater in the group Obese than in non-obese group. No correlation was noted between the mandibular unit length and OSA severity, The group of small mandibular unit length showed shorter lower facial height and maxillary unit length, and smaller cross-sectional area of tongue than the long mandibular unit length group. Hyold bone positioned more inferiorly and cross-sectional area of nasopharynx decreased as the OSA severity increased.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.551-560
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• 2003

Particle deposition in human lungs was investigated theoretically by using asymmetric five-lobe lung model. The volumes of each of the five lobes were different, thereby forming an asymmetric lung structure. The tidal volume and flow rate of each lobe were scaled according to lobar volume. The total and regional deposition with various breathing patterns were calculated by means of tracking volume segments and accounting for particle loss during inhalation and exhalation. The deposition fractions were obtained for each airway generation and lung lobe, and dominant deposition mechanisms were investigated for different size particles. Results show that the tidal volume and flow rate have a characteristic influence on particle deposition. The total deposition fraction increases with an increase in tidal volume for all particle sizes. However, flow rate has dichotomous effects: a higher flow rate results in a sharp increase in deposition for large size particles, but decreases deposition for small size particles. Deposition distribution within the lung shifts proximally with higher flow rate whereas deposition peak shifts to the deeper lung region with larger tidal volume. Deposition fraction in each lobe was proportional to its volume. Among the three main deposition mechanisms, diffusion was dominant for particles < 0.5 ${\mu}{\textrm}{m}$ whereas sedimentation and impaction were most influential for larger size particles. Impaction was particularly dominant for particles> 8 ${\mu}{\textrm}{m}$. The results may prove to be useful for estimating deposition dose of inhaled pollutant particles at various breathing conditions.

• Journal of Yeungnam Medical Science
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• v.23 no.2
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• pp.227-231
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• 2006

The Valsalva maneuver is described as an expiratory effort against a closed glottis or airway. It leads to elevation of retinal venous pressure and may result in retinal hemorrhage. A fifty two- year-old man presented with an acute reduction of central visual acuity in his right eye which occurred after considerable straining at stool. Detailed past medical history revealed that he suffered from chronic constipation and hypertension. There were one disc sized subhyaloid hemorrhage and three small intraretinal hemorrhages around the fovea at the dilated fundus examination. After three months of follow-up without any treatment, the retinal hemorrhages resolved without any sequelae. Here we report a patient with sudden visual loss and retinal hemorrhage.

• Biomedical Science Letters
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• v.6 no.2
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• pp.109-118
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• 2000

The bronchus and alveoli from young rats have been examined by electron microscope following the exposure of cigarette smoking. Experimental animals were exposed to the sidestream smoke in an experimentally designed cage for 45 minutes per day during four weeks. In the smoking group, transmission electron micrographs of lung tissues showed a large number of neutrophils with electron densed several lysosomes, numerous macrophages with many small lysosomes, and many residual bodies in alveolar space. Scanning electron micrographs revealed that the ciliated epithelial cells in bronchus of smoking group were replaced by goblet cells including loss of cilia, and increased cell size of many goblet cells in bronchus. These results depicted that the ultrastructural changes are due to the passive smoking, involving airway cell Injury.

• Fire Science and Engineering
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• v.21 no.2 s.66
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• pp.105-110
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• 2007

This investigation contains an awareness level on the Basic Emergency Treatment of Kindergarten Teacher in emergency surgery and internal medicine situations which frequently happen at the nursery. The result says there are 59.4% of them who are fully aware of the general emergency treatment but they need to know about education the partial parts. Especially 83.2% of them misunderstood the treatment of unconscious a small child with FBAO and 82.1% of them are confused with the manual ventilation. Also 67.4% of them said they would go to the hospital without giving first aid to a burn and 53.7% have wrong emergency treatment of abrasions. The educational program for the actual situation has been proposal as the responsibility of Kindergarten teachers are raising.

• Korean Journal of Bronchoesophagology
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• v.18 no.2
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• pp.56-59
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• 2012

Tracheo-innominate artery fistula (TIF) is a rare but catastrophic and almost always fatal complication of tracheostomy. TIF can occur anytime but is commonly present 3 to 24 days after tracheostomy. It can first manifest as massive bleeding around and through the tracheostomy tube, but it can also manifest as a small amount of blood with temporary spontaneous resolution. If TIF is suspicious, airway management and prompt surgical intervention are needed. In an 83-year-old man with CVA history 20 years earlier and who had recurrent aspiration pneumonia, tracheostomy was performed for respiratory management and ventilator support. On day 7 post-tracheostomy, the patient had bleeding from the tracheostoma. Immediate surgical exploration was performed to control the bleeding. A defect was seen at the post wall of the innominate artery. The erosive portion of the artery was sutured, but the patient died three weeks after the surgery due to rebleeding and respiratory failure. We present a patient who developed TIF after tracheostomy, with literature review.

• Journal of The Korean Dental Society of Anesthesiology
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• v.11 no.2
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• pp.177-182
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• 2011

There are five principal causes for excessive bleeding in the immediate postextraction phase ; (1) Vascular wall alteration (wound infection, scurvy, chemicals, allergy) (2) Disorders of platelet function (genetic defect, drug-aspirin, autoimmune disease) (3) Thrombocytopenic purpuras (radiation, leukemia), (4) Inherited disorders of coagulation (hemophilia, Christmas disease, vitamin deficiency, anticoagulation drug-heparin, coumarin, aspirin, plavix). If the hemorrhage from postextraction wound is unusually aggressive, and then dehydration and airway problem are occurred, the socket must be packed with gelatine sponge(Gelfoam) that was moistened with thrombin and wound closure & pressure dressing are applied. The thrombin clots fibrinogen to produce rapid hemostasis. Gelatine sponges moistened with thrombin provide effective coagulation of hemorrhage from small veins and capillaries. But, in dental alveoli, gelatine sponges may absorb oral microorganisms and cause alveolar osteitis (infection). This is a case report of bleeding and infection control by the circumferential suture and iodoform gauze drainage on infected active bleeding extraction socket under sedation and local anesthesia in a 71-years-old male patient with anticoagulation drug.

• Tuberculosis and Respiratory Diseases
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• v.79 no.2
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• pp.85-90
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• 2016

Background: Lung cancer is the most common cause of cancer related death. Alterations in gene sequence, structure, and expression have an important role in the pathogenesis of lung cancer. Fusion genes and alternative splicing of cancer-related genes have the potential to be oncogenic. In the current study, we performed RNA-sequencing (RNA-seq) to investigate potential fusion genes and alternative splicing in non-small cell lung cancer. Methods: RNA was isolated from lung tissues obtained from 86 subjects with lung cancer. The RNA samples from lung cancer and normal tissues were processed with RNA-seq using the HiSeq 2000 system. Fusion genes were evaluated using Defuse and ChimeraScan. Candidate fusion transcripts were validated by Sanger sequencing. Alternative splicing was analyzed using multivariate analysis of transcript sequencing and validated using quantitative real time polymerase chain reaction. Results: RNA-seq data identified oncogenic fusion genes EML4-ALK and SLC34A2-ROS1 in three of 86 normal-cancer paired samples. Nine distinct fusion transcripts were selected using DeFuse and ChimeraScan; of which, four fusion transcripts were validated by Sanger sequencing. In 33 squamous cell carcinoma, 29 tumor specific skipped exon events and six mutually exclusive exon events were identified. ITGB4 and PYCR1 were top genes that showed significant tumor specific splice variants. Conclusion: In conclusion, RNA-seq data identified novel potential fusion transcripts and splice variants. Further evaluation of their functional significance in the pathogenesis of lung cancer is required.