교정용 밴드 제거 후 미생물 분포 및 치주 조직의 임상적 변화

양유미,김성식,전은숙,박수병 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.4

본 연구는 밴드 제거 직후 및 4주 경과 후 치주조직의 임상적인 환경변화와 미생물 분포 변화를 알기 위해 시행하였다. 최후방 구치에 밴드를 포함하는 고정식 교정 장치를 장착하고 교정 치료를 1년 이상 시행한 17명의 환자를 대상으로 하였다 (평균 나이 22세, 남자 6명, 여자 11명). 최후방 구치의 밴드를 제거한 직후와 제거 후 4주가 경과한 다음에 치주조직의 탐침 깊이와 출혈 빈도를 측정하였으며, 치은 연하의 치태를 채취하여 미생물의 분포를 조사하였다. 치주질환에 관련성이 깊은 미생물 중 Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola를 직접 Polymerase Chain Reaction 방법으로 존재 여부를 확인하였다. 밴드 제거 직후와 제거 후 4주가 경과한 시점의 치주조직의 탐침 깊이와 출혈 빈도, 병원성 미생물의 존재 여부를 통계적으로 비교하였다. 탐침 깊이와 출혈 빈도는 모두 하악 좌측 구치 협면에서 감소율이 가장 크게 나타났고, 상악 우측 구치 설면에서 감소율이 가장 작게 나타났다. 병원성 미생물 중 T. denticola가 밴드 제거 4주 후에 가장 높은 감소율을 보였으며, 하악보다 상악에서 감소율이 더 크게 나타났다. 이는 비록 밴드를 장착하여 치주 환경이 불량해졌다 하더라도 올바른 구강 위생 관리가 시행된다면 밴드를 제거한 후 정상적인 치주 상태로 회복될 수 있음을 예시한 것으로 생각되었다. Objective: The purpose of this study was to evaluate clinical and microbiological changes in periodontal tissue around the banded molars after debanding. Methods: This study included 17 young adult patients treated with fixed orthodontic appliances including bands on the last molars more than 1 years. Probing depth and bleeding frequency were measured and plaque samples were collected from the last banded molars in all quadrants of each patient. All the data were collected immediately after debanding and 4 weeks after debanding. Results: Using polymerase chain reaction based on 16S rDNA, the presence of Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola was detected. After debanding, probing depth, bleeding frequency, and prevalance of periodontopathogens were reduced. Probing depth and bleeding frequency were most decreased in the buccal site of the mandibular left molar and were least decreased in the lingual site of the maxillary right molar. Conclusion: The results of this study indicated that proper management of oral hygiene after debanding can recuperate unfavorable periodontal condition caused by orthodontic treatment.

한의진단명과 진단요건의 표준화 연구 III : 3차년도 연구결과 보고

최선미,양기상,최승훈,박경모,박종현,심범상,김성우,노석선,이인선,정진홍,이진용,김달래,임형호,김윤범,박성식,송태원,김종우,이승기,최윤정,신순식 한국한의학연구원 1997 한국한의학연구원논문집 Vol.3 No.1

The diagnostic requirements were suggested and explained regarding the systems of differentiation of symptoms and signs in the third year study of standardization and unification of the terms and conditions used for diagnosis in oriental medicine. The systems were as follows : - analyzing and differentiating of epidemic febrile disease - analyzing and differentiating in accordance with the Sasang constitution medicine based on four-type recognition - differentiation of disease according to pathological changes of Chong and Ren channels - standards for diagnosis of women's disease - standards for diagnosis of children's disease - standards for diagnosis of motor and sensor disturbance (-muscle. born, joint, etc.) - standards for diagnosis of neuropsychiatric disease - standards for diagnosis of five sense organ disease - standards for diagnosis of external disease The indivisual diagnosis pattern was arranged by the diagnostic requirements in the following order : another name, notion of diagnosis pattern, index of differentiation of symptoms and signs, the main point of diagnosis, analysis of diagnosis pattern, discrimination of diagnosis pattern, prognosis, a way of curing a disease, prescription, herbs in common use, disease appearing the diagnosis pattern, documents. The standards for diagnosis of each disease was arranged by the diagnostic requirements in the following order : another name, notion of disease, the main point of diagnosis, analyzing and differentiating of disease, analysis of disease, discrimination of disease, prognosis, a way of curing and prescription of disease, disease in western medicine appearing the disease in oriental medicine, documents.

5년간 특수건강진단기관 분석정도관리 결과 분석

강성규,양정선,이미영,박인정,정호근 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목 적 : 1980년대 후반부터 산업보건에서 혈중 및 요중 중금속농도 분석의 정확성 문제가 크게 부각되었다. 같은 시료를 가지고 분석기관마다 보이는 커다란 오차로 인해 직업병 진단 결과에 대한 신뢰성을 크게 감소시켰다. 이에, 노동부에서는 1992년부터 특수건강진단 기관에 대한 생체시료 분석정도관리 프로그램을 시작하였다. 본 연구는 1995년부터 시작된 생체시료 분석정도관리 5년간의 결과를 보고하고, 현재 생물학적모니터링으로 사용되는 항목과 빈도를 조사하고 이 항목의 정도관리 참여율을 비교하여 산업보건 관계 연구나 직업병 관리에 참고할 수 있도록 하기 위해 실시하였다. 방 법 : 생체시료 분석정도관리는 무기와 유기분석분야로 나누어 일년에 전후반기 2회 실시하고 있으며, 지정항목과 자율항목으로 구분하고 있다. 지정항목인 혈중 납과 요중 마뇨산은 분야별로 한 번에 3개 농도수준을 주어 2개 이상이 기준값의 ±15%내외의 범위에 들면 적합한 것으로 판정하고 있으며, 자율항목은 2개의 시료를 주어 2개 모두 기준실험실 평균값의 ±3SD 내외의 범위에 들면 적합한 것으로 판정하고 있다. 결 과 : 지정항목인 혈중 납과 요중 마뇨산 분석은 평균 적합률이 각각 89%, 90% 이었고, 대학기관, 비영리법인, 종합병원, 사업장 자체기관별로 차이는 없었으나 신규 기판의 적합률 70% 수준으로 상대적으로 낮았다. 자율항목의 적합률은 평균 50% 수준이었고, 저농도보다는 고농도의 적합률이 떨어졌다. 국내에서 가장 많이 분석되고 있는 항목은 요중 마뇨산과 혈중 납이었고, 혈중 및 요중 망간도 많이 분석되고 있었다. 요중 삼염화물, 페놀, 만델산, 카드윰, 메칠마뇨산, 크롬 등도 많이 분석되고 있는 항목이었다. 혈중 망간, 요중 수은, 요중 NMF는 정도관리에서 적합판정을 받은 기관의 숫자보다 실제 분석을 하고 있는 기관의 숫자가 많았다. 결 론 : 지난 5년간의 생체시료 분석정도관리 결과 우리나라 분석실험실의 분석능력은 향상되고 있으나, 자율항목에 대한 분석능력은 아직 미흡한 것으로 나타났다. 그리고, 아직 일부 일부 항목에 대해서는 외부 정도관리 없이 분석되고 있는 경우도 있었다. Objective : The accuracy of analytical results of blood and urine heavy metals came out to the main issue on occupational health from late eighties. The discrepancy of the results for same samples from different laboratories made the diagnosis for occupational diseases be unreliable. Therefore, a quality control program for analysis of samples taken from workplace had been introduced in Korea since 1992. This study aims to show the quality control program for analysis of blood and urine samples and its proficient rates from 1992 to 1999 and to know how they have been being used in occupational health. Methods The quality control program runs twice a year with mandatory items of blood lead and urine hippuric acid and voluntary items of blood cadmium and manganese and urine mandellic acid and methyl hippuric acid. Participant laboratories are receiving three levels for each items and two out of three samples have to be qualified for being a profi-cient laboratory for the item. The acceptable range of blood lead and urine hippuric acid is ± 15% and that of the others is within 3 SD (standard deviation) from the reference values. Results : The proficient rates of blood lead and urine hippuric acid was 89%, 90%, repectively, however those of the other voluntary items have been from 51% to 62%. The proficient rates of urine mercury and urine N-methylformamide (NMF), which are introduced since 1999, were very poor. Urine hippuric acid and blood lead were analyzed frequently for the purpose of biological monitoring conducting by special health examination organizations. Urine and blood manganese and urine metabolites of trichloroethylene, urine phenol, methylhippuric acid and cadmium were followed. Conclusions : In conclusion, the quality control program for biological monitoring has dramatically improve the ability of analysing blood and urine samples and eventually con-tributes to diagnose occupational diseases and to prevent occupational poisoning. However, some biological monitoring data, such as urine manganese, mercury and NMF, have been still reported from laboratories that were not accepted as a proficient laboratory.

Phosphamidon 분해세균의 분리동정 및 생분해능

강양미,허성남,안태석,송홍규 江原大學校 附設 環境硏究所 1999 環境硏究 Vol.16 No.-

토양으로부터 유기인계 살충제인 phosphamidon을 분해하는 세균들을 분리하고 Biolog system을 이용하여 동정하였다. 그람양성 세균들은 모두 Bacillus 속에 속하는 종들이었으며 그람음성 세균들은 토양에서 우점하지 않는 세균들이 많았다. 이들중 phosphamidon 함유배지에서 생장률이 높은 균주들을 선택하여 phosphamidon 분해능을 조사한 결과 Capnocytophaga gingivalis로 동정된 YD-17 균주가 가장 높은 생분해능을 나타내어 1000 ppm의 phosphamidon이 배양 21일 후 9.4%의 잔류량을 보였으며 이는 대조구에 비해 제거율이 52% 증가된 결과였다. 이 때 균주의 생장을 단백질량으로 측정하였는데 분해균주들이 고농도의 phosphamidon에 의해 저해되지 않고 지속적인 생장을 하여 phosphamidon을 탄소원으로 이용하는 생분해가 일어난 것을 확인할 수 있었다. Organphosphorus insecticide phosphamidon-degrading bacteria were isolated from agricultural soils and identified using Biolog microtiter assay. All Gram-ositive degrading bacterial strains belong to genus Bacillus and many Gram-negative bacteria were rare soil species. Among them fast growing strains on phospamidon-containing minimal medium were selected and their biodegrading capability were measured. YD-17 which was identified as Capnocytophaga gingivalis showed the highest biodegradation rate. It could increase the removal of phosphamidon up to 52%. During the biodegradation continuous increase of amount of cell protein was observed, which, indicated that phosphamidon was utilized as a carbon source for phosphamidon-degrading bacteria.

창의적 문제해결을 위한 웹기반 교수-학습 모형과 학습 환경 설계 : 수학교과에서의 예시를 중심으로

구양미,김영수,노선숙,조성민 이화여자대학교 사범대학 교과교육연구소 2006 교과교육학연구 Vol.10 No.1

본 연구의 목적은 지식기반사회의 학습도구로서 그 중요성이 증대되고 있는 인터넷과 웹을 활용하여 창의성 계발을 돕는 교수-학습 모형과 웹기반 학습 환경을 설계하는 데 있다. 본 연구에서 웹은 학습도우미(learning agent)로서 문제해결 학습상황에서 의사소통도구, 발견과 탐색도구, 지식과 경험 구성의 도구로 상정되었다. 즉, 중등 수학교과를 사례로 채택, 문제해결 학습상황에서 생각 5단계 모형(생각 열기, 생각 쌓기, 생각 나누기, 생각 다지기, 생각 펼치기)을 토대로 각 단계별로 문제의 구조 유형에 따른 사고 전략과 이에 상응하는 학습자와 교수자 활동, 웹기반 활동을 포함하는 웹기반 교수-학습 모형을 설계하였다. 설계된 웹기반 교수-학습 모형에 따라 실제 교수-학습활동 계획안을 개발하고, 창의적 문제해결 환경 지원을 목적으로 한 웹사이트를 설계하였다. 본 연구의 결과물인 웹기반 교수-학습 모형과 학습 환경은 창의적 문제해결을 위한 핵심요소로 간주되는 확산적 사고, 비판적 사고 및 교과지식이 조화롭게 활용될 수 있도록 하는데 그 주안점을 두고 있다. The purpose of this study is to design a web-based teaching and learning model and learning environment for creative problem solving in Mathematics. In this study, World Wide Web is considered as a learning agent assisting learning process as communication tools, inquiry tool, and knowledge construction tools in problem solving learning environments. The web-based teaching and learning model was developed based on "Five Stage Thinking Model" that consists of uncover ideas, accumulate ideas, share ideas, ensure ideas, and unfold ideas. According to the steps of the model, a web-based lessen plan on coordinates in middle school mathematics was developed. Finally, a web-based their divergent thinking, critical thinking and subject knowledge for mathematical problem solving creatively. Some sample web pages were suggested for developing a web site based on the purposed model and the lessen plan.

대동맥 판막 치환술 후 반복되는 Acinetobacter baumannii 균혈증의 원인이 된 대동맥염 1예

정용필,김성철,송은희,장은영,김은경,김윤지,성흥섭,김미나,최상호,우준희,김양수 대한감염학회 2007 감염과 화학요법 Vol.39 No.3

감염성 대동맥염은 흔하지 않지만 매우 위중한 질병으로 Salmonella so.와 S. aureus가 주된 원인균이다. 아직까지 병원내 감염의 주요 원인균인 Acinetobacter baumannii에 의한 감염성 대동맥염은 보고된 바가 없었다. 저자들은 대동맥 판막 치환술을 시행받은 76세 남자 환자에서 적절한 항생제 투여에도 반복되는 A. baumannii 균혈증의 원인이 감염성 대동맥염으로 진단되었던 1예를 경험하였기에 보고하는 바이다. Infectious aortitis is an uncommon yet, life threatening disease. Early surgical treatment and prolonged antibiotic therapy is crucial to survival. Salmonella sp. and Staphylococcus aureus are the most common organisms isolated. There is no case report of infectious aortitis caused by Acinetobacter baumannii, which has recently emerged as a major cause of health care-associated infections. Here, we describe a 76-year-old male with infectious aortitis who experienced recurrent bacteremia due to A. baumannii in spite of adequate antimicrobial therapy after aortic valve replacement.

Southern Blot Hybridization법을 이용한 악성 림프종의 면역유전형에 관한 연구

전호종,기근홍,김윤신,이미숙,이미자,장원재,장숙진,박영진,정춘해,정종훈,양성훈,이광민 조선대학교 1994 The Medical Journal of Chosun University Vol.19 No.2

Immunogenotyping using gene rearrangement analysis has emerged as a precise laboratory aid in the diagnosis and classification of malignant Iymphoid neoplasms. The lineage and clonality of the malignant Iymphoid neoplasms can be identified by the demonstration of rearrangements of antigen receptor genes of the immunoglobulin and T-cell receptor genes. The analysis of the gene rearrangements on the malignant Iymphoid neoplasms are also useful as a sensitive unique clonal markers to detect early recurrence in patients with malignant Iymphoid neoplasms after treatment. To analyze the sensitivity and specificity of gene rearrangements in the diagnosis of malignant Iymphoid neoplasms. 24 cases of malignat Iymphoma were examined by Southern blot hybridization using CTβ-T cell receptor β chain gene-DNA probe and JH-immunoglobulin heavy chain gene-DNA probe. The results of the immunogenotypings using Southern blot hybridization disclosed high correlation between the immunophenotyping using immunohistochemical stain with monoclonal antibodies (B-cell Iymphoma 84.2%. T-cell Iymphoma 75% ). The analysis of the gene rearrangement of the angioimmunoblastic lymphadenopathy(AILD) and unclassifiable Iymphoma using immunohistochemical stain could resolve the monoclonality and lineage . Rearranged bands to the CTβDNA probe were observed in one case out of 2 cases of AILD. One case of unclassifiable Iymphoma showed rearranged bands to the CTβ DNA probe. There were no rearrangements in reactive follicular Iymphoid hyperplasia and paracortical Iymphoid hyperplasia. In conclusion, DNA gene rearrangement study should be applied to differentiate the clonality and cell lineage in the malignant Iymphoma with indistinctive immunophenotype.

직업적 아크릴아미드 폭로에 의한 다발성 신경병증

정해관,권용욱,어경윤,김병준,양정선,정철,진영우,이미영,강성규 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.3

Authors report a first Korean case of polyneuropathy in an acrylamide producing factory together with an environmental and epidemiologic survey for the ten workers of the same workplace and 46 workers in the production and manufacturing acrylamide in Ulsan, Korea. The case is 30 years old man who worked in the production of the acrylamide for two years. In August, 1997, he had a weakness of the lower extremity with loss of body weight of 15 Kg which progressed to paresthesia of the limbs, the loss of vibration sense, difficulty in walking, speech disturbance, dysuria, constipation, difficulty in erection and swallowing difficulty. Neurologic examination showed a complete loss of vibration and position sense, and loss of deep tendon reflex in all the limbs. There was a contact dermatitis-like skin lesion on the feet. Electrodiagnostic test showed a generalized polyneuropathy of moderate degree involving motor and sensory component of peripheral and cranial nerves. After 8 months' cessation from exposure and supportive care, his symptoms were completely resolved, but abnormality in electrodiagnostic test and vibrotactile perception threshold still persisted, although much improved than before. There were 11 workers in the same workplace of the case, producing acrylamide by microorganism as a catalyst. Environmental monitoring of the workplace revealed air borne concentration of the acrylamide to be from 0.05 to 0.23 mg/m3 by personal sampling and from 7.65 to 11.65 mg/m3 by area sampling during filter exchanging process, which far exceeds TLV-TWA of 0.03 mg/m3. However, acrylamide was not detected from the plasma of the workers. Symptom questionnaire showed a markedly higher complain of neurologic symptoms, compared to the workers of the other acrylamide producing companies. Electrodiagnostic test showed a several workers are in the lower normal range without definite abnormality. Vibrotactile perception threshold by Vibratron Ⅱ showed a significantly increased threshold in the workers of the same workplace compared to the other acrylamide workers and significantly decreased test score of color vision compared to normal controls. After improvement of the production process and strict wearing of the protective device, most workers reported the improvement of clinical symptoms, but vibrotactile perception threshold was not improved. These result suggests the need for the effective environmental monitoring together with a periodic biological monitoring. Development of effective screening test is urgently needed to control and assess the skin absorption of acrylamide.

임상검체에서 분리된 그람 음성 세균들에 대한 Isepamicin의 시험관내 항균력

권현희,박수진,소민욱,박현구,최성호,김미나,최상호,정진용,우준희,김양수 대한감염학회 2006 감염과 화학요법 Vol.38 No.6

Background : The increasing incidence of multidrug-resistant gram-negative bacteria causing nosocomial infections is an important clinical problem. Isepamicin is a recently developed aminoglycoside which has been known to have potent activity against gram-negative organisms. We evaluated the in vitro activities of isepamicin and other aminoglycosides against a large number of gram-negative organisms. Materials and Methods : We tested the in vitro antimicrobial activities of isepamicin, amikacin, gentamicin, and tobramycin against 566 gram-negative organisms collected between January 2006 and June 2006 in Asan Medical Center. Minimal inhibitory concentrations (MICs) were determined and interpreted according to the recommendations of Clinical and Laboratory Standard Institute (CLSI). The breakpoint MIC used for interpretation of isepamicin was MIC≤16 ㎍/mL as susceptible, 32 ㎍/mL as intermediate, and 64 ㎍/mL as resistant. Results : The MIC_(50)/MIC_(90) of isepamicln for Escherichia coli, Klebsiella pneumon/ae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacter cloacae were 1/2, 0.5/>128, 4/16, 16/>128, and 1/2 ㎍/mL, respectively. The susceptibilities for E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, and E. cloacae were 100%, 86.4%, 89.7%, 50.0%, and 96.6%, respectively. For E. coli, K. pneumoniae, P. aeruginosa, and E. cloacae, isepamicln had better in vitro activities than gentamicin and tobromycin, and had similar activities with amlkacin. For A. baumanii, all four tested aminoglycosides had similar in vitro activities. Conclusion : Isepamicin had excellent in vitro activities against gram-negative organisms, except A. baumanii. The overall in vitro activities were similar with amikacin. 목적 : 그람 음성 세균은 다양한 지역사회 및 병원 획득 감염의 원인균이다. 최근에는 병원 감염을 일으키는 그람 음성 세균에서 항균제 내성균의 출현과 확산이 큰 문제가 되고 있다. Isepamicin은 최근에 소개된 gentamicin B의 유도체로 외국에서의 연구에 의하면 그람 음성 세균들에 대한 항균력이 우수함이 보고 된 바 있다. 본 연구에서는 우리나라의 임상 균주들을 대상으로 그람 음성세균에서 isepamicin의 시험관내 항균력을 기존의 아미노배당체 제재들과 비교하여 평가하고자 하였다. 재료 및 방법 : 2006년 1월에서 6월 사이에 서울아산병원 환자에서 분리된 Escherichia coli 113 균주, Klebsiella pneumoniae 110 균주, Pseudomonas aeruginosa 117 균주, Acinetobacter baumannii 108 균주, 그리고 Enterobacter cloacae 118 균주를 대상으로 isepaimcin, amikacin, gentamicin, tobramycin에 대한 최소억제농도(minimal inhibitory concentration, MIC)를 한천 희석법(Mueller-Hinton Agar)을 이용하여 측정하였다. 감수성여부는 CLSI 기준에 따랐으며, isepamicin은 MIC≤16㎍/mL를 감수성, MIC=32 ㎍/mL를 중등도 내성, MIC≥64 ㎍/mL를 내성으로 판정하였다. 결과 : Isepamicm의 E. coli, K. pneumoniae, P. aeruginosa, A baumannii, E. cloacae에 대한 MIC_(50)/MIC_(90)은 각각 1/2, 0.5/>128, 4/16, 16/>128, 1/2 ㎍/mL였고, 항균제 감수성률은 차례대로 100%, 86.4%, 89.7%, 50.0%, 96.6%였다. 기존 아미노배당체 제재들과 비교하면 E. coli, K. pneumoniae, P. aeruginosa, E. cloacae에서는 amikacin과 비슷한 감수성률을 보였고, gentamicin과 tobramycin보다 높은 감수성률을 보였다. A baumannii의 경우 isepamicin의 감수성률이 50.0%로 비교적 낮았지만 amikacin, gentamicin, tobramycin도 각각 50.0%, 46.3%, 47.2%의 감수성률을 나타내어 4가지 항균제가 모두 비슷한 항균력을 보였다. 결론 : Isepamicin은 그람 음성 세균들에 있어 기존의 아미노배당체 제재들과 비교했을 때 amikacin과는 동등한 시험관내 항균력을 보이고 gentamicin, tobramycin보다 뛰어난 시험관내 항균력을 보여 사용이 유망한 아미노배당체 중 하나라 생각된다.

Pulmonary Toxicity and Recovery from Inhalation of Manual Metal Arc Stainless Steel Welding Fumes in Rats

Mi-Jin Yang,Jin-Sung Kim,Young-Su Yang,Jae-Woo Cho,Seong-Bong Choi,Yong-Hyun Chung,Yong-Bum Kim,Kyu-Hyuk Cho,Chae-Woong Lim,Choong-Yong Kim,Chang-Woo Song 한국독성학회 2008 Toxicological Research Vol.24 No.2

The objectives of this study were to examine the lung injury and inflammation caused by manual metal arc stainless steel (MMA-SS) welding fume inhalation and to evaluate the recovery process. Sprague-Dawley rats were exposed to MMA-SS welding fumes for 2 h per day in a whole-body exposure chamber, with a total suspended particulate (TSP) concentration of 51.4 ± 2.8 ㎎/㎥ (low dose) or 84.6 ± 2.9 ㎎/㎥ (high dose) for 30 days. The animals were sacrificed after 30 days of exposure as well as after a 30-day recovery period. To assess the inflammatory or injury responses, cellular and biochemical parameters as well as cytokines were assayed in the bronchoalveolar lavage fluid (BALF). MMA-SS welding fume exposure led to a significant elevation in the number of alveolar macrophages (AM) and polymorphonuclear cells (PMN). Additionary, the values of β-nacetyl glucosaminidase (β-NAG) and lactate dehydrogenase (LDH) in the BALF were increased in the exposed group when compared to controls. After 30 days of recovery from exposure, a significant reduction in inflammatory parameters of BALF was observed between the exposed and recovered groups. Slight, but significant elevations were noted in the number of AM and PMN in the recovered groups, and AM that had been ingested fume particles still remain in the lungs. In conclusion, these results indicated that welding fumes induced inflammatory responses and cytotoxicity in the lungs of exposed rats. Fume particles were not fully cleared from lungs even after a 30-day recovery period.