1.Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry
Chungsik YOON ; Sunju KIM ; Donguk P PARK ; Younsoon CHOI ; Jihoon JO ; Kwonseob LEE
Safety and Health at Work 2020;11(4):500-508
Background:
Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective.
Methods:
Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined.
Results:
On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16–56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials.
Conclusion
We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.
2.Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry
Chungsik YOON ; Sunju KIM ; Donguk P PARK ; Younsoon CHOI ; Jihoon JO ; Kwonseob LEE
Safety and Health at Work 2020;11(4):500-508
Background:
Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective.
Methods:
Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined.
Results:
On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16–56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials.
Conclusion
We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.
3.Isolated Posteroinferior Cerebellar Artery Dissection Diagnosed by High-Resolution Vessel Wall MRI.
Hea Ree PARK ; Jaechun HWANG ; Ye Sel KIM ; Juhyeon KIM ; Hyunjin JO ; Young Hee JUNG ; Jihoon CHA ; Sung Tae KIM ; Gyeong Moon KIM
Journal of the Korean Neurological Association 2016;34(3):209-212
Arterial dissection is an important cause of stroke. We report two cases of isolated posterior inferior cerebellar artery (PICA) dissection diagnosed by high-resolution vessel-wall MRI (HRVW-MRI). One subject complained of abrupt-onset vertigo and headache, and the other subject had headache, vertigo, and Horner syndrome. Conventional MRA showed only focal dilatation of the PICA, but HRVW-MRI revealed intramural hematoma and double-lumen contour in the PICA, suggesting arterial dissection. We suggest that the use of HRVW-MRI should be considered when diagnosing isolated PICA dissection in a PICA infarct with an unknown cause.
Arteries*
;
Dilatation
;
Headache
;
Hematoma
;
Horner Syndrome
;
Magnetic Resonance Imaging*
;
Pica
;
Stroke
;
Vertigo
5.Ischemic Stroke with Cerebral Vasculopathy in POEMS Syndrome
Sung Woo KANG ; Bo Kyu CHOI ; Hee Jo HAN ; Soo Mi CHO ; Jihoon CHA ; Hyo Suk NAM ; Ji Hoe HEO ; Young Dae KIM
Journal of the Korean Neurological Association 2018;36(4):350-353
Ischemic stroke caused by the cerebral vasculopathy is a rare complication of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome. We present a case of recurrent ischemic strokes caused by cerebral vasculopathy in a patient with POEMS syndrome. A 34-year-old man presented with gait disturbance and dizziness. Brain magnetic resonance imaging demonstrated acute ischemic stroke in the middle cerebral artery-anterior cerebral artery (MCA-ACA) border zones of bilateral hemispheres. Repeated angiographic studies showed progressive worsening of the left distal internal carotid artery, ACA, and MCA stenoses, along with sustained steno-occlusion of right MCA.
Adult
;
Brain
;
Carotid Artery, Internal
;
Cerebral Arteries
;
Constriction, Pathologic
;
Dizziness
;
Gait
;
Humans
;
Magnetic Resonance Imaging
;
Paraproteinemias
;
POEMS Syndrome
;
Polyneuropathies
;
Skin
;
Stroke
;
Vascular Diseases
6.Warthin Tumor on the Parotid Gland: A Case Report
Sungchang MIN ; Kyuho YOON ; Kwansoo PARK ; Jeongkwon CHEONG ; Jungho BAE ; Kyuhong JO ; Jihoon HAN ; Youngil OH ; Jaemyung SHIN ; Jeeseon BAIK
Journal of the Korean Association of Maxillofacial Plastic and Reconstructive Surgeons 2012;34(6):473-479
7.Extracellular Vesicles Derived from Adipose Stem Cells Alleviate Systemic Sclerosis by Inhibiting TGF-β Pathway
Eunae KIM ; Hark Kyun KIM ; Jae Hoon SUL ; Jeongmi LEE ; Seung Hyun BAEK ; Yoonsuk CHO ; Jihoon HAN ; Junsik KIM ; Sunyoung PARK ; Jae Hyung PARK ; Yong Woo CHO ; Dong-Gyu JO
Biomolecules & Therapeutics 2024;32(4):432-441
Systemic sclerosis is an autoimmune disease characterized by inflammatory reactions and fibrosis. Myofibroblasts are considered therapeutic targets for preventing and reversing the pathogenesis of fibrosis in systemic sclerosis. Although the mechanisms that differentiate into myofibroblasts are diverse, transforming growth factor β (TGF-β) is known to be a key mediator of fibrosis in systemic sclerosis. This study investigated the effects of extracellular vesicles derived from human adipose stem cells (ASC-EVs) in an in vivo systemic sclerosis model and in vitro TGF-β1-induced dermal fibroblasts. The therapeutic effects of ASC-EVs on the in vivo systemic sclerosis model were evaluated based on dermal thickness and the number of α-smooth muscle actin (α-SMA)-expressing cells using hematoxylin and eosin staining and immunohistochemistry. Administration of ASC-EVs decreased both the dermal thickness and α-SMA expressing cell number as well as the mRNA levels of fibrotic genes, such as Acta2, Ccn2, Col1a1 and Comp. Additionally, we discovered that ASC-EVs can decrease the expression of α-SMA and CTGF and suppress the TGF-β pathway by inhibiting the activation of SMAD2 in dermal fibroblasts induced by TGF-β1. Finally, TGF-β1-induced dermal fibroblasts underwent selective death through ASC-EVs treatment. These results indicate that ASC-EVs could provide a therapeutic approach for preventing and reversing systemic sclerosis.
8.Extracellular Vesicles Derived from Adipose Stem Cells Alleviate Systemic Sclerosis by Inhibiting TGF-β Pathway
Eunae KIM ; Hark Kyun KIM ; Jae Hoon SUL ; Jeongmi LEE ; Seung Hyun BAEK ; Yoonsuk CHO ; Jihoon HAN ; Junsik KIM ; Sunyoung PARK ; Jae Hyung PARK ; Yong Woo CHO ; Dong-Gyu JO
Biomolecules & Therapeutics 2024;32(4):432-441
Systemic sclerosis is an autoimmune disease characterized by inflammatory reactions and fibrosis. Myofibroblasts are considered therapeutic targets for preventing and reversing the pathogenesis of fibrosis in systemic sclerosis. Although the mechanisms that differentiate into myofibroblasts are diverse, transforming growth factor β (TGF-β) is known to be a key mediator of fibrosis in systemic sclerosis. This study investigated the effects of extracellular vesicles derived from human adipose stem cells (ASC-EVs) in an in vivo systemic sclerosis model and in vitro TGF-β1-induced dermal fibroblasts. The therapeutic effects of ASC-EVs on the in vivo systemic sclerosis model were evaluated based on dermal thickness and the number of α-smooth muscle actin (α-SMA)-expressing cells using hematoxylin and eosin staining and immunohistochemistry. Administration of ASC-EVs decreased both the dermal thickness and α-SMA expressing cell number as well as the mRNA levels of fibrotic genes, such as Acta2, Ccn2, Col1a1 and Comp. Additionally, we discovered that ASC-EVs can decrease the expression of α-SMA and CTGF and suppress the TGF-β pathway by inhibiting the activation of SMAD2 in dermal fibroblasts induced by TGF-β1. Finally, TGF-β1-induced dermal fibroblasts underwent selective death through ASC-EVs treatment. These results indicate that ASC-EVs could provide a therapeutic approach for preventing and reversing systemic sclerosis.
9.Extracellular Vesicles Derived from Adipose Stem Cells Alleviate Systemic Sclerosis by Inhibiting TGF-β Pathway
Eunae KIM ; Hark Kyun KIM ; Jae Hoon SUL ; Jeongmi LEE ; Seung Hyun BAEK ; Yoonsuk CHO ; Jihoon HAN ; Junsik KIM ; Sunyoung PARK ; Jae Hyung PARK ; Yong Woo CHO ; Dong-Gyu JO
Biomolecules & Therapeutics 2024;32(4):432-441
Systemic sclerosis is an autoimmune disease characterized by inflammatory reactions and fibrosis. Myofibroblasts are considered therapeutic targets for preventing and reversing the pathogenesis of fibrosis in systemic sclerosis. Although the mechanisms that differentiate into myofibroblasts are diverse, transforming growth factor β (TGF-β) is known to be a key mediator of fibrosis in systemic sclerosis. This study investigated the effects of extracellular vesicles derived from human adipose stem cells (ASC-EVs) in an in vivo systemic sclerosis model and in vitro TGF-β1-induced dermal fibroblasts. The therapeutic effects of ASC-EVs on the in vivo systemic sclerosis model were evaluated based on dermal thickness and the number of α-smooth muscle actin (α-SMA)-expressing cells using hematoxylin and eosin staining and immunohistochemistry. Administration of ASC-EVs decreased both the dermal thickness and α-SMA expressing cell number as well as the mRNA levels of fibrotic genes, such as Acta2, Ccn2, Col1a1 and Comp. Additionally, we discovered that ASC-EVs can decrease the expression of α-SMA and CTGF and suppress the TGF-β pathway by inhibiting the activation of SMAD2 in dermal fibroblasts induced by TGF-β1. Finally, TGF-β1-induced dermal fibroblasts underwent selective death through ASC-EVs treatment. These results indicate that ASC-EVs could provide a therapeutic approach for preventing and reversing systemic sclerosis.