• Title/Summary/Keyword: Respiratory protection

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Construction of Recombinant BCGs Overexpressing Antigen 85 Complex and Their Protective Efficacy against Mycobacterium tuberculosis Infection in a Mouse Model (항원 85 복합체를 과발현하는 재조합 BCG의 개발 및 마우스 모델에 있어서의 결핵균 감염에 대한 방어 효능)

  • Lee, Seung-Heon;Jeon, Bo-Young;Park, Young-Gil;Lee, Hye-Young;Cho, Sang-Nae;Kim, Hyo-Joon;Bai, Gill-Han
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.2
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    • pp.125-131
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    • 2004
  • Tuberculosis (TB) remains an enormous global health problem, and a new vaccine against TB more potent than the current inadequate BCG vaccine is urgently needed. We constructed three recombinant Mycobacterium bovis BCG (rBCG) strains over-expressing antigen (Ag) 85A, Ag85B, or both of M. tuberculosis using their own promoter and secretory sequence, or hsp60 promoter. SDS-PAGE analysis of rBCG proteins showed overexpression of Ag85A and Ag85B proteins in higher level than of those in their parental strain of BCG. In addition, rBCG(rBCG/B.FA) over-expressing Ag85A and Ag85B induced strong IFN-${\gamma}$ production in splenocytes. However, there was no significant difference in protective efficacy between rBCG and their parental BCG strain. In this study, therefore, rBCG over-expressing Ag85A, Ag85B, or both failed to show enhanced protection against M. tuberculosis infection in a mouse model.

A Case Report: Limitation of Mouth Opening in Dermatomyositis (개구장애를 동반한 피부근염 환자 증례)

  • Kim, Hye-Kyung;Kim, Ki-Suk;Kim, Mee-Eun
    • Journal of Oral Medicine and Pain
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    • v.35 no.2
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    • pp.155-163
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    • 2010
  • Dermatomyositis (DM) is an idiopathic inflammatory connective tissue disorder and a systemic autonomic immune disease which shows a progressive muscle weakness and characteristic rash. It is identified by a characteristic rash accompanying, or more often preceding muscle weakness. Pathognomonic skin lesions are a blue-purple discoloration on the upper eyelids with edema (heliotropic rash), a flat red rash on the face and upper trunk, and erythema of the knuckles with a raised violaceous scaly eruption (Gottron's papule). The myopathy represents inflammatory and degenerative changes primarily affecting proximal muscles. DM often involves GI tract and respiratory system with as risk of 15-25% internal malignancy. It's managed with sun protection since muscle weakness as well as a rash could be aggravated by sun exposure. Systemic corticosteroid is an initial therapy and other immunosuppressive agent has been used as alternatives. Facial muscles are unaffected and masticatory muscles are rarely affected in DM. We present trismus close to muscle contracture in a patient with DM. Therefore, it needs continuous mouth-opening exercise to prevent progressive muscle contracture and to ensure normal mouth opening.

Studies on the Morphology of Smoke Particles for Each Type of Fire by Using Steady State Tube Furnace (등속공급 튜브연소로를 이용한 각 연소조건에서의 연기입자 형상 분석)

  • Goo, Jaehark
    • Fire Science and Engineering
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    • v.28 no.1
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    • pp.44-51
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    • 2014
  • Smoke from fire is a mixture of combustion gases and particles which include micro-droplets formed from condensed organic vapors and carbonaceous agglomerates. The inhalation of smoke particles causes adverse health effects, and it is prerequisite for the hazard and risk analysis of the smoke particles to know how they behaviour in the respiratory tract. The characteristics of the absorption and adsorption of toxic gases and the amount and location of the particle deposition within the respiratory tract that determine the adverse health effects are related to the morphology and the size distribution of smoke particles. In the present work, as a preliminary study for the adverse health effects of smoke particles, the morphologies of the smoke particles from combustible materials were investigated for each fire stage: smouldering, well-ventilated flaming, small under-ventilated flaming, fully-developed under-ventilated fire. The steady-state tube furnace method given in ISO/TS 19700 was used for the generation of smoke particles. The fire stages were controlled by changing furnace temperature and equivalent ratio. The morphologies were analyzed by using Transmission Electron Microscope (Bio-TEM) by collecting the particles on TEM grids put on each stage of a cascade impactor.

A Study of Dermal and Ocular Exposure to Isocyanate-Based Paints in Crash Repair Workshops (차량수리업에서 사용하는 이소시안계 페인트에 의한 피부와 눈의 노출에 관한 연구)

  • Lee, Su-Gil;Pisaniello, Dino;Lee, Nae-Woo;Tkaczuk, Michael
    • Journal of the Korean Society of Safety
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    • v.24 no.6
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    • pp.72-78
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    • 2009
  • Exposure to HDI(hexamethylene di-isocyanate) commonly used in vehicle crash repair workshops remains a leading cause of occupational asthma. Although skin and eye contamination are considered as absorption routes, there are no occupational exposure standards for skin and ocular exposure. This is the reason why there are more empirical data should be provided. Therefore this study was to determine contamination levels of HDI on the skin, eyes, work surfaces, respirators and eye protectors. There was evidence of contamination on a variety of work surfaces, for example, door handles, bench top and spray gun, etc. A high proportion(47~80%) of skin wipe samples from neck, forehead, back hand, palm and wrist was positive for HDI contamination, even though spray time was relatively brief. The contamination levels from spraying inside spray booth were generally higher than outside booth due to poor work practices and inappropriate personal protective use like safety gloves. Apprentices had higher exposure levels than the qualified painters, likely due to lack of the recognition of safety and hygiene. The extent of contamination inside the PPE might provide an indication of the potential for respiratory & skin exposure and ocular exposure. Eye fluid samples from 4 out of 14 workers had the positive detection of HDI contamination, due to poor work practices like no or inappropriate eye protection. Considering the potential for dermal & ocular exposure to contribute to possible health symptoms including respiratory sensitization, the empirical data point to a need for improving work practices and appropriate PPE selection, use and maintenance.

Effects of mixed supplementation on Hoveni dulcis Thunb extracts and Ginseng-Berry extracts on hangover curves (헛개과병추출물과 인삼열매추출물의 혼합 음료 섭취가 숙취해소에 미치는 효과)

  • Park, Noh-Hwan;Lee, Jeong-Ok;Cho, In-ho
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.3
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    • pp.359-367
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    • 2019
  • The purpose of this study was to investigate the effects of ingestion of rabies and ginseng fruit extracts on alcohol hangover, liver damage protection, fatigue recovery, and physical strength improvement. A total of 64 volunteers aged over 20 were participated in this study and the randomized and repeated measures design method was used to divide a group of participants with a random assignment. All participants were divided into 4 groups (n=16) treated with hoveni dulcis thunb extract + ginseng berry extract (ARI 1000), hoveni dulcis thunb extract, ginseng berry extract, and placebo. As a result of respiratory alcohol concentration change, the group treated with ARI 1000 was significantly lower than the group treated with hoveni dulcis thunb extract, ginseng berry extract, and placebo in 1 hour of drinking, and significantly lower than the placebo group in 2 hours and 3 hours of drinking (p<0.05). After 2 and 3 hours of alcohol consumption, blood alcohol concentration of the group treated with rabies ARI 1000 was significantly lower than those of the other 3 groups (p <0.05). In conclusion, ingestion of ARI 1000 before drinking may significantly reduce the respiratory and blood alcohol concentrations, which may induce an effect on the hangover effect.

Guidelines for dental clinic infection prevention during COVID-19 pandemic (코로나 바이러스 대유행에 따른 치과 의료 관리 가이드라인)

  • Kim, Jin
    • Journal of Korean Academy of Dental Administration
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    • v.8 no.1
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    • pp.1-7
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    • 2020
  • Dental settings have unique characteristics that warrant specific infection control considerations, including (1) prioritizing the most critical dental services and provide care in a way that minimizes harm to patients due to delayed care, or harm to personnel from potential exposure to persons infected with the COVID-19 disease, and (2) proactively communicate to both personnel and patients the need for them to stay at home if sick. For health care, an interim infection prevention and control recommendation (COVID-19) is recommended for patients suspected of having coronavirus or those whose status has been confirmed. SARS-CoV-2, which is the virus that causes COVID-19, is thought to be spread primarily between people who are in close contact with one another (within 6 feet) through respiratory droplets that are produced when an infected person coughs, sneezes, or talks. Airborne transmission from person-to-person over long distances is unlikely. However, COVID-19 is a new disease, and there remain uncertainties about its mode of spreads and the severity of illness it causes. The virus has been shown to persist in aerosols for several hours, and on some surfaces for days under laboratory conditions. COVID-19 may also be spread by people who are asymptomatic. The practice of dentistry involves the use of rotary dental and surgical instruments, such as handpieces or ultrasonic scalers, and air-water syringes. These instruments create a visible spray that can contain particle droplets of water, saliva, blood, microorganisms, and other debris. While KF 94 masks protect the mucous membranes of the mouth and nose from droplet spatter, they do not provide complete protection against the inhalation of airborne infectious agents. If the patient is afebrile (temperature <100.4°F)* and otherwise without symptoms consistent with COVID-19, then dental care may be provided using appropriate engineering and administrative controls, work practices, and infection control considerations. It is necessary to provide supplies for respiratory hygiene and cough etiquette, including alcohol-based hand rub (ABHR) with 60%~95% alcohol, tissues, and no-touch receptacles for disposal, at healthcare facility entrances, waiting rooms, and patient check-ins. There is also the need to install physical barriers (e.g., glass or plastic windows) in reception areas to limit close contact between triage personnel and potentially infectious patients. Ideally, dental treatment should be provided in individual rooms whenever possible, with a spacing of at least 6 feet between the patient chairs. Further, the use of easy-to-clean floor-to-ceiling barriers will enhance the effectiveness of portable HEPA air filtration systems. Before and after all patient contact, contact with potentially infectious material, and before putting on and after removing personal protective equipment, including gloves, hand hygiene after removal is particularly important to remove any pathogens that may have been transferred to the bare hands during the removal process. ABHR with 60~95% alcohol is to be used, or hands should be washed with soap and water for at least 20 s.

A Study on the Exposure Factors Used in the Assessment of Inhalation Exposure to Household Chemicals (생활화학제품의 흡입노출평가에 사용되는 노출계수에 대한 고찰)

  • Yoon, Chungsik;Kwon, Taehong;Oh, Gitaek;Kim, Minjung;Kim, Boowook;Shin, CheolWoong;Lee, Kiyoung;Zoh, Kyungduk
    • Journal of Environmental Health Sciences
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    • v.48 no.4
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    • pp.195-205
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    • 2022
  • Background: The biggest concern when using household chemical products is the health risk from inhalation exposure. Objectives: The purpose of this paper was to provide information necessary for estimating inhalation exposure factors in several countries/organizations and to present some examples. Methods: We attempted to use PRISMA-ScR for a systematic review, but no major reports were found. We used the Google search function instead to find 'exposure factor handbook'. As for the results, inhalation exposure factors from South Korea, the United States, Canada, the EU, Australia, Japan, and China were compared. Results: The basic concept and origin of exposure factors was the US Environmental Protection Agency's Exposure Factor Handbook. Its latest version is 2011, but several chapters have been updated in 2017, 2018, and 2019. South Korea's Exposure Factor Handbook was updated in 2019, more recently than those of other countries, and was systematically investigated. In South Korea, the average daily respiratory rate is 14.62 m3/day for adults and 12.73 m3/day for children. It is difficult to compare breathing rate by country because each country divides age groups differently and uses different methods to estimate it. Information on household chemical products, space used, and ventilation rate are in the exposure factor handbook in some countries and not in others. It is not in the handbook in South Korea, but in the notice from the NIER (National Institute of Environmental Research), a sub-regulation of the Chemical Product Safety Act. Conclusions: The exposure factors registered in South Korea's exposure factor handbook have been systematically studied and reflect the most recent data. When using data not in the relevant handbook, data from other countries might be applied, but it should be determined whether the nature and quality of the original data have been managed.

A Study on the Anticonvulsant Effects of Centrally-Acting Drugs by Measuring Electroencephalography of Experimental Animals Intoxicated with Organophosphate Compounds (실험동물의 뇌파 측정에 의한 중추약물의 항경련효과 연구)

  • Cho, Young;Kim, Wang-Soo;Hur, Gyeung-Haeng
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.2
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    • pp.218-224
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    • 2013
  • Organophosphorus compounds are irreversible inhibitors of cholinesterase enzyme. Exposure causes a progression of toxic signs, including hypersecretion, tremor, convulsion, respiratory distress, epileptiform seizure, brain injuries and death. To protect brain injuries, administration of diazepam as a neuroprotectant is now considered essential for severely exposed nerve agent casualties. However, studies have shown diazepam to provide less than total protection against the neuropathological consequences of nerve agent exposure. In this context, extensive studies have been carried out to find out effective alternative drugs to protect brain from epileptiform seizures induced by organophosphate compounds intoxication. It has been reported that a combination of carbamate and anticholinergic or antiglutamatergic can be a very effective medical countermeasure in dealing with the threat of organophosphorous poisoning. In this study, experimental animals including rats and guinea pigs were implanted with microelectrodes on their brain sculls, and treated with various centrally acting drugs such as physostigmine and procyclidine prior to soman challenge, and then its electroencephalography(ECoG) was monitored to see anticonvulsant effects of the drugs. It was found that seizure activities in ECoG were not always in proportion to clinical signs induced by soman intoxication, and that combinative pretreatment with physostigmine plus procyclidine effectively stopped the seizures induced by organophosphorous poisoning.

Risk assessment of di(2-ethylhexyl) phthalate in the workplace

  • Kim, Hyeon-Yeong
    • Environmental Analysis Health and Toxicology
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    • v.31
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    • pp.11.1-11.6
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    • 2016
  • Objectives A hazard assessment of di(2-ethylhexyl) phthalate (DEHP), a commonly used workplace chemical, was conducted in order to protect the occupational health of workers. A literature review, consisting of both domestic and international references, examined the chemical management system, working environment, level of exposure, and possible associated risks. This information may be utilized in the future to determine appropriate exposure levels in working environments. Methods Hazard assessment was performed using chemical hazard information obtained from international agencies, such as Organization for Economic Cooperation and Development-generated Screening Information Data Set and International Program on Chemical Safety. Information was obtained from surveys conducted by the Minister of Employment and Labor ("Survey on the work environment") and by the Ministry of Environment ("Survey on the circulation amount of chemicals"). Risk was determined according to exposure in workplaces and chemical hazard. Results In 229 workplaces over the country, 831 tons of DEHP have been used as plasticizers, insecticides, and ink solvent. Calculated 50% lethal dose values ranged from 14.2 to 50 g/kg, as determined via acute toxicity testing in rodents. Chronic carcinogenicity tests revealed cases of lung and liver degeneration, shrinkage of the testes, and liver cancer. The no-observed-adverse-effect level and the lowest-observed-adverse-effect level were determined to be 28.9 g/kg and 146.6 g/kg, respectively. The working environment assessment revealed the maximum exposure level to be $0.990mg/m^3$, as compared to the threshold exposure level of $5mg/m^3$. The relative risk of chronic toxicity and reproductive toxicity were 0.264 and 0.330, respectively, while the risk of carcinogenicity was 1.3, which is higher than the accepted safety value of one. Conclusions DEHP was identified as a carcinogen, and may be dangerous even at concentrations lower than the occupational exposure limit. Therefore, we suggest management of working environments, with exposure levels below $5mg/m^3$ and all workers utilizing local exhaust ventilation and respiratory protection when handling DEHP.

Effect of shearing on some physiological and hormonal parameters in Akkaraman sheep

  • Pehlivan, Erkan;Kaliber, Mahmut;Konca, Yusuf;Dellal, Gursel
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.5
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    • pp.848-855
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    • 2020
  • Objective: Shearing is one of the practices that is applied periodically to fiber producing animals, which can also alter resistance of animals to high temperatures in especially summer months. This study aimed to investigate effects of shearing on some physiological and hormonal parameters in Akkaraman sheep during summer season. Methods: This study was carried out on 39 non-pregnant Akkaraman ewes (aged 1.5 years at the beginning of experiment). The 39 ewes were chosen randomly from the flock belonging to the Erciyes University and they were assigned to two groups as follows: i) group A (n = 20) designed as the control group, they were shorn and group B (n = 19) designed as the experimental group, they were unshorn. Prior to the shearing (-1 day) and on days 1, 7, 15, 30, 45, 60, 75, and 90 following the shearing, blood samples were taken from the vena jugularis of each sheep. Cortisol, β-endorphin, growth hormone (GH), thyroxine (T4), triiodothyronine (T3), and heat shock protein 70 (HSP-70) concentrations were determined using the enzyme immunoassay method. Body weight (BW), rectal temperature (RT), pulse rate (PR), and respiratory rate (RR) of each sheep were recorded at the same time. The data obtained were analyzed using two-way repeated measures analysis of variance. Results: Statistical analysis showed a significant effect of shearing×period interaction (p<0.01) and a significant effect of period (p<0.01) on BW, HSP-70, cortisol, T4 and RT, PR, GH, β-endorphin, T3, respectively. Also these analysis showed no significant effect of shearing×period interaction or period on RR. Conclusion: The results showed that the thermoregulation abilities of sheep were affected by shearing treatment and the shorn ewes were less affected by heat stress. In conclusion, based on the data of this study, shearing can be considered as a necessary management practice that requires protection for sheep from the effect of heat stress.