• 한국환경보건학회지
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• 제46권5호
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• pp.481-494
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• 2020

Objectives: No study has been conducted to review characteristics of humidifier disinfectants (HD) products, such as real numbers, levels and types of HD substances contained, or the volume marketed. We aimed to review the characteristics of HD through a literature review. Methods: We collected literature reporting the names, numbers, and ingredients of HD and discussed them with a focus on the number of HD products and the chemicals used as a disinfectant. Results: A total of eight publications has reported the names of HD brands or types of disinfectants from 2011 to 2020. To date, a total of 40 HD products have been used, excluding four products. Eight HD products used polyhexamethylene guanidine phosphate (PHMG) and 14 used a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) as disinfectants. Benzalkonium chloride (BKC) and sodium dichloroisocyanurate (NaDCC) were also used as a disinfectant in several HD products. A total of 19 HD products were associated with the development of HD associated lung injury (HDLI). The Oxy Saksak HD product containing PHMG showed the highest number of HD associated health effects. The type of disinfectant from a total of 14 HD products has not been identified. Conclusions: A total of 40 HD products have been marketed in South Korea since 1994. Further studies should be conducted to identify the association of product characteristics, including type of HD ingredients, with health effects.

• 한국환경보건학회지
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• 제46권5호
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• pp.495-503
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• 2020

Objective: This study aimed to compare the characteristics of humidifier disinfectant-like products (HD-like products) and humidifier disinfectant products (HD products) and introduce actual cases of the usage of HD-like products in hospitals based on an on-site investigation. Methods: The characteristics, chemical components, and usage of HD-like products (Hichlor or Biospot) and HD products (N-with) containing NaDCC (sodium dichloroisocyanurate) were compared. In the process of conducting the on-site investigation, four hospitals were identified as previously using HD-like products. Each on-site investigation to identify the use of HD-like products was composed of four parts: 1) hospital infection control guidelines, 2) manual for humidifiers in patient's rooms, 3) interviews with nursing staff, infection managers, and purchase managers, 4) searching on the product purchase system. Results: Although HD-like products (Hichlor and Biospot) and HD products (N-with) were sold for different usage purposes, they were all white-colored and coin-shaped foaming tablets with the same chemical component, NaDCC. The manual for using HD-like products and HD products was similar (inserting the tablet in a humidifier container with water). Among the four hospitals, one had used Hichlor in the same manner as HD (N-with) by inserting a tablet in 1L of water in a filled humidifier container and Biospot as a kind of detergent for humidifier container cleaning. Another two hospitals had used Biospot and/or Aniosyme as a kind of detergent for humidifier container cleaning. The other hospital had used unknown product in the same manner as N-with, so we thus assumed it was either an HD products (N-with) or HD-like products (Hichlor, Biospot). Conclusion: This study raises the possibility of the development of adverse health effects similar to exposure to an HD-products when exposed to an HD-like products and the possibility of further use in other medical institutions or multi-use facilities. Therefore, an expansion of the investigation is needed in order to confirm whether there have been similar cases in the past.

• 한국환경보건학회지
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• 제46권4호
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• pp.433-443
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• 2020

Objective: This study aimed to introduce the use of humidifier disinfectant (HD) in hospitals based on an on-site investigation. Methods: A preliminary survey and on-site investigation of HD use were conducted in 23 hospitals. Among them, one hospital without previous information on HD use was selected for a pilot investigation; 22 hospitals were selected based on previous documents and exposure statements from parliamentary investigation and exposure assessment regarding HD. Descriptive statistics were used to present distribution and characteristics of HD purchase and HD use in hospitals. Also, details on interviews from the on-site investigation were described. Results: Among the 23 hospitals, a total of ten were confirmed to have purchased and used an HD (nine hospitals) or HD-like product (one hospital). For the purchased HD products, four hospitals reported 'Aekyung Gaseupgi Mate', two hospitals reported 'Oxy Ssakssak New Gaseupgi Dangbun', and one hospital reported 'Homeplus Gaseupgi Chungjungje' (one hospital used three kinds of HD products). One hospital reported an HD-like product and four hospitals were 'Unknown'. For the number of HD products purchased, five hospitals reported '100 or less', two hospitals reported 'More than 100', and three hospitals were 'Unknown'. For each of the ten hospitals, we described detailed characteristics of HD purchase and its exposure status obtained through on-site investigation, including the purchase volume (i.e., number of products), exposure space (i.e., patient's room, staff space), and exposure period. Additionally, a comparison of on-site investigation and parliamentary investigation or exposure assessment regarding HD was reported. Conclusion: This study introduced detailed cases of HD purchase and HD use in hospitals based on an on-site investigation, and our findings revealed a possibility of a considerable volume of HD exposure in various multiuse facilities, including hospitals.

• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.634-641
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• 1998

Quasiclassical trajectory calculations were carried out for the reactions of $H+H_2$ (V=O, J=O) and its isotope variants on the Siegbahn-Liu-Truhlar-Horowitz potential energy surface for the relative energies E between 6 and 150 kcal/mol. The goal of the work was to understand the inter- and intramolecular isotope effects. We examine the relative motion of reactants during the collision using the method of analysis that monitors the intermolecular properties (internuclear distances, geometry of reactants, and final product). As in other works, we find that the heavier the incoming atom is, the greater the reaction cross section is at the same collision energy. Using the method of analysis we prove that the intermolecular isotope effect is contributed mainly by differences in reorientation due to the different reduced masses. We show that above E=30 kcal/mol recrossing also contributes to the intermolecular isotope effect. For the intramolecular isotope effect in the reactions of H+HD and T+HD, we reach the same conclusions as in the systems of $O(^3P)+HD$, F+HD, and Cl+HD. That is, the intramolecular isotope effect below E=150 kcal/mol is contributed by reorientation, recrossing, and knockout type reactions.

• 한국응용과학기술학회지
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• 제40권6호
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• pp.1278-1288
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• 2023

헤스페리딘(Hesperidin, HD)은 다양한 식물체에 존재하는, 강한 항산화 기능을 가진 대표적인 flavonoid의 일종이다. 본 연구에서는 수용성 HD인 Hesperidin glucoside(HDG)가 가지는 세포손상 회복, 항염증 인자억제 및 melanin 생성억제 활성을 세포수준에서 비교하였다. HDG는 HD에 당전이 효소반응으로 제조되었으며, HD에 비해 20,000배 이상 수용해도가 증가되었다. HaCaT 세포주에 대한 세포독성은 HDG가 HD에 비해 월등히 낮았다. HD와 HDG는 모두 자외선 조사된 HaCaT 세포에서 세포생존율 회복효과를 나타내었다. 또한 HD와 HDG는 세포내 산화질소(NO), 종양괴사인자-α(TNF-α) 및 인터루킨-6(IL-6)과 같은 염증 매개체 및 cytokine을 감소시켰으며, HD 보다는 HDG의 효과가 다소 우수하였다. Melanoma B16F10 세포주를 이용한 melanin 형성능과 tyrosinase 저해활성을 측정한 결과, HD와 HDG 모두 효과를 나타내었으며 HDG가 약간 우수한 결과를 보였다. 결론적으로, HD의 당전이체인 HDG는 HD에 비해 동등이상의 세포손상 회복, 염증성 매개체 및 cytokine 억제능과 melanin 형성억제능을 나타내었으며, HDG의 높은 수용성과 낮은 세포독성 등의 특성은 다양한 분야에서의 용도를 확대시킬 수 있을 것으로 보인다.

• 한국잠사곤충학회지
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• 제35권1호
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• pp.36-42
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• 1993

Bacillus thruingiensis subsp. kurstaki HD-1의 내독소단백질 유전자인 CryIA(a)의 N-말단 부분과 B.tk HD-73의 내독소단백질 유전자인 CryIA(c)의 C-말단 부분의 융합에 따른 독성발현 여부에 관하여 조사하였다. 융합생산물인 pSK3, pSK4 및 pSK5의 플라스미드는 각각 4.5kb, 4.8kb 그리고 5.5kb로 구성되어 있다. 형질전환체의 내독소단백질에 대한 Western blotting은 SK4 및 SK5가 77-kDa 그리고 105-kDa에서 B.t k HD-1 항체에 대하여 반응을 나타내었다. 독성검정의 공시충인 배추좀나방 및 담배나방을 사용한 결과 pSK5를 포함하는 형질전환체만이 각각 96% 및 97%의 높은 치사율을 나타냈다.

• 전력전자학회지
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• 제9권6호
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• pp.32-35
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• 2004

• 한국환경보건학회지
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• 제49권3호
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• pp.159-168
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• 2023

Background: An ongoing environmental exposure assessment of humidifier disinfectants (HDs) has been conducted since November 2011 among individuals who experienced HD exposure-related adverse health effects. It is being performed in order to determine and quantify exposure to humidifier disinfectants in victims and their families. To date, the assessment has encompassed Cycles I-to-V. There is no report summarizing the characteristics of the subjects from the overall cycles. Objectives: We intended to examine the individual characteristics related to demographics, HD usage, and HD exposure using integrated data from Cycles I-to-V of the environmental exposure assessment of HDs and the changes with the cycles. Methods: We included 7,543 individuals who participated in Cycles I-to-V of the environmental exposure assessment of HDs. We summarized the participants' characteristics regarding their demographics (e.g., sex, education level, and age), HD usage history (e.g., product name, ingredient, and frequency of HD use), and HD exposure (e.g., daily time of HD use, cumulative time of HD use, and exposure intensity). In addition, their characteristics were compared across the cycles of the exposure assessment. Results: Among the 7,543 participants from Cycles I-to-V, there were more male participants than females (51.05% overall), except for Cycles I and III. Across all cycles, a higher proportion of survivors was observed than deceased individuals. While PHMG was the most prevalent ingredient in HDs throughout all the cycles, its proportion gradually decreased over the course of the examination cycles. Participants in Cycle I reported longer daily times of HD use compared to those in the subsequent cycles. On the other hand, cumulative time of HD use was shorter in the earlier cycles than in the later cycles. Conclusions: Using the integrated data from the full cycles of the environmental exposure assessment, this study identified changes in demographic characteristics as well as the HD exposure characteristics between the participants across different cycles.

• Food Science and Biotechnology
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• 제17권4호
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• pp.700-704
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• 2008

Anti-obesity effects of $\beta$-cyclodextrin in obese C57BL/6J mice induced by a high fat diet (HD) were observed. The administration of $\beta$-cyclodextrin reduced the gain of body weight, abdominal fat, liver weight, the lipid deposits of hepatocytes and the size of adipocytes in the HD group. In serum analysis, the total and low-density lipoprotein-cholesterols were significantly decreased in the $\beta$-cyclodextrin-supplemented HD group than in the HD group. However, high-density lipoprotein-cholesterol was not changed in these groups. In hypothalamic homogenates, the decrease of neuropeptide Y and increase of $\alpha$-melanocyte stimulating hormone were detected in the $\beta$-cyclodextrin-supplemented HD group compared to that in the HD group. These effects of $\beta$-cyclodextrin were similar to those of Garcinia cambogia, which is widely used as a natural anti-obesity product. These results suggest that $\beta$-cyclodextrin has anti-obesity effects through the lowering of the abdominal fat pad and inhibits the central effects of hunger.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.660-664
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• 2000

UK-58,852의 생합성에 관여하는 유전자를 분리하기 위해 Actinomadura roseorufa의 genomic DNA와 E. coli-Streptomyces shuttle cosmid vector인 pOJ446이 genomic library를 만들었다. Genomic library는 dehydratase PCR product와 eryA 유전자를 probe로 하여 sugar 생합성 유전자와 polyketide typel 유전자가 집단으로 존재하는 cosmid pHD54를 분리하였고, 이를 제한 효소인 BamHI, SmaI와 Sonicater를 이용해서 subcloning 하였다. 이들의 염기서열을 부분 분석한 결과, polyketide 생합성에 관여하는 ketoacyl synthase, methylmalonyl acyltransferase, ketoreductase, enolreductase 그리고 PKS loading domain 등 polyketide synthase type I 임을 보여주고 있고, BLAST 분석된 결과를 보면 polyketide synthase 유전자는 rifamycin 생합성 유전자와 유사성이 높다. 그리고 sugar 생합성에 관여하는 유전자로는 oxidoreductase, dTDP-D-glucose 4,6 dehydratase, dTDP-D-glucose synthase 그리고 dTDP-4-keto-6-deoxy-D-glycose 3,5-epimerase으로 구성된 gene cluster를 확인하였다. 그리고 염기서열 분석된 유전자중 dTDP-D-glucose synthase를 발현하여 유전자의 기능을 확인하였다.