OBJECTIVETo develop a method for determination of 2, 4-dichlorophenoxyacetic acid (2, 4-D) in the air of workplace by high-performance liquid chromatography.

METHODS2, 4-D was collected by ultrafine glass filters, desorbed by methanol, separated by a C18 column, and detected by a UV detector. Identification and quantification of 2, 4-D were performed by retention time and peak areas, respectively.

RESULTSThe linear range of the test was 2∼200 µg/ml; the elution efficiency was 94.6%- 95.9%; the limit of detection (S/N = 3) was 0.034 µg/ml (injection volume of 20 µl eluant); the lower limit of quantification (S/N = 10) was 0.11 µg/ml; the minimum detectable concentration was 0.011 mg/m(3); the minimum quantifiable concentration was 0.037 mg/m(3) (with sampled air volume of 45 L).

CONCLUSIONThis method is convenient and simple in sample collection and preparation, and satisfies all methodological requirements. Therefore, this method is useful for the determination of 2, 4-D in the air of workplace.

2,4-Dichlorophenoxyacetic Acid ; analysis ; Air ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography, High Pressure Liquid ; methods ; Workplace

2,4-Dichlorophenoxyacetic acid is a component of agent orange, which was spread during Vietnam War. Due to the toxicity of this agent, several diseases may be occuring today, potentially causing social problem. The author tried to take as preliminary information for a further clinical study by examining whether 2,4-dichlorophenoxyacetic acid makes any change in the retina of a white rat histopathologically. The objects were 6 white rats of 200-300 gm in weight. After diluting 40% 2,4dichlorophenoxyacetic acid, it was injected intraperitoneally into the rats at the levels of 5 mg/kg, 10 mg/kg, 15 mg/kg of agent. The eyeballs of the each groups were enucleated on 24 hours and 3 days and examinated with an electron microscope. Histopathological changes in the retina were characterized by the degeneration of the retinal pigment epithelial cells, the photoreceptor cells, and the choriocapillaris. To prove that 2,4-dichlorophenoxyacetic acid injures human retina, experiments with futher various plans and epidemiological surveys should be provided.
2,4-Dichlorophenoxyacetic Acid ; Animals ; Citrus sinensis ; Epithelial Cells ; Humans ; Injections, Intraperitoneal* ; Photoreceptor Cells ; Rats* ; Retina* ; Retinaldehyde ; Social Problems ; Vietnam

Water extracts of six plants, such as Allium sativum, A. cepa, Zingiber officinale, Platycodon grandiflorum, Oenanthe javanica, and Capsella brusapastoris, were tested in vitro for inhibitory activity against mycelial growth of anthracnose fungi, Colletotrichum gloeosporioides, C. dematium, and C. coccodes. Among the plant extracts, an Allium sativum extract has good inhibitory effects in all the fungi. Four phytohormones namely, IAA (indole-3-acetic acid), NAA (a-Naphthyl acetic acid), 2,4-D (2,4-Dichloro phenoxy acetic acid) and BAP (Benzyl adenine purine) were used to find out the role over mycelial growth of these fungi. All the concentrations of BAP have good inhibitory effect against mycelial growth of these fungi than that of other tested plant hormones.
2,4-Dichlorophenoxyacetic Acid ; Adenine ; Capsella ; Colletotrichum ; Fungi* ; Garlic ; Ginger ; Oenanthe ; Plant Extracts* ; Plant Growth Regulators* ; Plants* ; Platycodon ; Water

A defoliant is a toxic chemical agent used to remove leaves. Defoliants are classified into 6 types (purple, pink, green, blue, white and orange). From 1962 to 1971, due to removing leaves and securing their ability to see, the U.S. Army Chemical Corps veterans handled and sprayed defoliant in Vietnam. This resulted in exposure to Agent Orange and its contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD or dioxin). This agent induces many medical problems in humans. Since 1992 in Korea, exposure to defoliants have given rise to several problems. However, there were few reactions due to the lack of data, social apathy, and international relationships. In this article, we review characteristics and diseases related to defoliants.
2,4,5-Trichlorophenoxyacetic Acid ; 2,4-Dichlorophenoxyacetic Acid ; Apathy ; Citrus sinensis ; European Continental Ancestry Group ; Humans ; Korea ; Skin ; Skin Diseases ; Tetrachlorodibenzodioxin ; Veterans ; Vietnam

Merkel cell carcinoma is a rare aggressive primary skin cancer which mostly occurs in the elderly on sun-exposed skin. It usually presents as a solitary dome-shaped red or purple nodule on the head, neck and extremities. The mortality rate is higher than the rate for malignant melanoma because its local recurrence is common. Agent Orange, an herbicide widely used as a defoliant in the Vietnam War, contains dioxin contaminants and can cause several dermatoses and skin cancers. We report a case of multiple Merkel cell carcinoma in a 65-year-old male with lesions on the head and neck, who had been exposed to Agent Orange during Vietnam War.
2,4,5-Trichlorophenoxyacetic Acid ; 2,4-Dichlorophenoxyacetic Acid ; Aged ; Carcinoma, Merkel Cell ; Citrus sinensis ; Extremities ; Head ; Humans ; Male ; Melanoma ; Neck ; Recurrence ; Skin ; Skin Diseases ; Skin Neoplasms ; Tetrachlorodibenzodioxin ; Veterans ; Vietnam

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), one of the components of Agent Orange, has been reported to be a deadly poison despite its presence at extremely small doses. TCDD is reported to cause various kinds of cancers and other harmful effects on humans. However, a correlation between exposure to TCDD and acute coronary syndrome (ACS) is not yet proven. Thus, we examined the correlation between exposure to TCDD and ACS through an analysis of coronary angiograms from veterans of the Vietnam War. Two hundred fifty-one consecutive men undergoing coronary angiograms owing to ACS between April 2004 and May 2009 at Gwangju Veterans Hospital were analyzed. Included subjects were between 50 and 70 years of age. The patients were divided into two groups: 121 patients who had been exposed to TCDD (Group I) and 130 patients who had not been exposed to TCDD (Group II). Clinical and coronary angiographic findings were evaluated. Baseline clinical characteristics, inflammatory markers, and echocardiographic parameters were not significantly different between the two groups. The incidence of hypertension (71.1% vs. 60.0%, p=0.039) and hyperlipidemia (27.3% vs. 16.9%, p=0.038) was higher in Group I than in Group II. Total occlusion, stent length, stent use, and coronary lesion characteristics were not significantly different between the two groups. The rate of major adverse cardiovascular events (MACE) had no relationship with exposure to TCDD. Exposure to TCDD might not affect severity or the rate of MACE in persons with ACS.
2,4,5-Trichlorophenoxyacetic Acid ; 2,4-Dichlorophenoxyacetic Acid ; Acute Coronary Syndrome ; Angiography ; Citrus sinensis ; Hospitals, Veterans ; Humans ; Hyperlipidemias ; Hypertension ; Incidence ; Male ; Stents ; Tetrachlorodibenzodioxin ; Veterans ; Vietnam

Conventional breeding for dual resistance of disease and pest of Musa cultivars remains a difficult endeavor, as the plant is polyploidic and high in sterility. Biotechnological techniques, eg., genetic engineering, in vitro mutation breeding, or protoplast fusion, may overcome the difficulties and improve the germplasm. Establishment of a stable embryogenic cell suspension (ECS) is a prerequisite for any of the biotechnological breeding methods. In this study an embryogenic cell suspension was established from immature male flower of Musa acuminata cv. Mas (AA), a popular commercial variety of banana in the South-East Asian region. After culture for 5-6 months on callus induction media, which consisted of MS salts, different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), 4.1 micromol/L biotin, 5.7 micromol/L indoleacetic acid (IAA), 5.4 micromol/L naphthaleneacetic acid (NAA), other vitamins, 87 mmol/L sucrose, and solidified with 7 g/L agarose, meristematic globules and yellow, friable embryogenic cultures were induced from the explants of 1-15th row young floral hands of immature male flowers. Of the four treatments of 2,4-D, 9 micromol/L was the most effective on the callus induction, it transformed 40.96% and 7.45% of the cultivated male floral hands into callus and embryogenic callus respectively. The explants to produce highest frequency of the embryogenic calli were floral hands of 6 to 12th rows, which generated 5.79% of the embryogenic calli. Suspension cultures were initiated from these embryogenic calli in liquid medium supplemented with 4.5 micromol/L 2, 4-D. After sieving selection of the cultures using a stainless steel metallic strainer with pore sizes of 154 microm at 15 day intervals for 3 months, homogeneous and yellow embryogenic cell suspensions, composed of single cells and small cell aggregates, were established. Based upon the growth quantity and growth rate of ECS, it was determined that the appropriate inoculum was 2.0 mL PCV ECS/30 mL medium in 100 mL flask, and the appropriate subculture cycle was 15 days. Planting of 6 months old ECS on semi-solid medium of somatic embryo induction and development (MSD) resulted in approximately 280 x 10(3) somatic embryos/mL PCV ECS. MSD contained SH macronutrients, micro-nutrients, Fe-EDTA and MS vitamins supplemented with 4.5 micromol/L biotin, 680 micromol/L glutamine, 2 mmol/L proline, 100 mg/L malt extract, 1.1 micromol/L NAA, 0.2 micromol/L zeatin, 0.5 micromol/L kinetin, 0.7 micromol/L N6-(2-isopentenyl) adenine, 29 mmol/L lactose, 130 mmol/L sucrose and solidified with 2g/L gelrite. After 3 months of maturity on MSD, 17.28% of the somatic embryos were germinated on germination media (MG), consisted of MS salt, Morel and Wetmore vitamins, 0.2 micromol/L 6-BA, 1.1 micromol/L IAA, 87 micromol/L sucrose and solidified with 2 g/L gelrite; and 14.16% of the somatic embryos could develop into normal plantlets on rooting media contained the same composition as that of MG but without auxin and cytokinin.
2,4-Dichlorophenoxyacetic Acid ; pharmacology ; Culture Media ; Flowers ; drug effects ; embryology ; physiology ; Musa ; drug effects ; embryology ; physiology ; Plant Physiological Phenomena ; Regeneration ; Tissue Culture Techniques ; methods

BACKGROUND: Self-inflicted dermatosis is a kind of self-inflicted skin disease. Most Vietnam veterans from Korea have visited the Veterans Hospitals for dermatological examination to determine the relationship between their skin diseases and Agent Orange. We were suspicious of the possibility that several Vietnam veterans intentionally produced their own skin lesions. OBJECTIVE: We conducted this study to determine the clinical characteristics of self-inflicted dermatoses of Korean Vietnam veterans. METHODS: From January, 1999 to December, 2007, a total 24 Vietnam veterans who were diagnosed as having self-inflicted dermatoses during their dermatological examinations at our hospital were included in this study. We investigated their clinical presentation, the laboratory examinations, the pathologic examinations, the medical records and the associated diseases. RESULTS: Itching was the most common subjective complaint and the duration of the itching was as follows; 20 to 30 yrs (50.0%), 1 to 10 yrs (25.0%), 10 to 20 yrs (20.8%) etc. The skin lesions were all multiple, and the involved area was as follows; upper extremities (83.3%), trunk (75.0%), lower extremities (70.8%) etc. There were two categories of clinical skin presentation. The first was the cases with lesion that were thought to be made by physical trauma such as stinging or excoriation, and the second more common cases had lesions that were thought to be made by chemical agents (70.8%). These cases resembled allergic or toxic irritant dermatitis and the lesions were composed of vesicles, erosions, ulcers and crusts that were within an arm's reach. Only 4 cases admitted to intentionally inflicting their skin lesions because of intense itching, and the others denied that they made the skin lesions by themselves. Skin biopsies were carried out in 19 of the total 24 cases, and the most common finding was spongiotic dermatitis (57.8%). CONCLUSION: This study showed the distribution and characteristics of self-inflicted dermatoses, and the study provides fundamental data for dermatologists to assess patients with self-inflicted dermatoses.
2,4,5-Trichlorophenoxyacetic Acid ; 2,4-Dichlorophenoxyacetic Acid ; Biopsy ; Bites and Stings ; Citrus sinensis ; Dermatitis ; Dermatitis, Irritant ; Hospitals, Veterans ; Humans ; Intention ; Korea ; Lower Extremity ; Medical Records ; Pruritus ; Skin ; Skin Diseases ; Tetrachlorodibenzodioxin ; Ulcer ; Upper Extremity ; Veterans ; Vietnam

OBJECTIVETo determine the content of baicalin in Scutellaria baicalensis callus induced by different doncentrations of exogenous hormones.

METHODHPLC system was adopted to determine baicalin in S. baicalensis callus. Chromatographic conditions: ODS column was adopted, with methanol-water-phosphate (47: 53: 0.2) as the mobile phase. The flow velocity was 1 mL x min(-1), the detective wavelength was 280 nm, and the temperature of column was room temperature.

RESULTS. baicalensis callus induced by 6-BA 1.0 mg x L(-1) + NAA 0.5 mg x L(-1) showed the highest baicalin content, up to 49.78 mg x g(-1).

CONCLUSIONThe experiment is such a simple, rapid and stable method for determining the baicalin content that it can be used for determining the baicalin content in S. baicalensis callus.

2,4-Dichlorophenoxyacetic Acid ; pharmacology ; Benzyl Compounds ; Chromatography, High Pressure Liquid ; Dose-Response Relationship, Drug ; Flavonoids ; metabolism ; Kinetin ; pharmacology ; Naphthaleneacetic Acids ; pharmacology ; Plant Growth Regulators ; pharmacology ; Purines ; Scutellaria baicalensis ; drug effects ; metabolism ; Tissue Culture Techniques ; methods

Wild cotton species can contribute a valuable gene pool for agronomically desirable cultivated tetraploid cultivars. In order to exploit diploid cotton a regeneration system is required to achieve transformation based goals. The present studies aimed at optimizing the conditions for regeneration of local varieties as well as wild species of cotton. Different callus induction media were tested with varying concentrations of hormones in which sucrose was used as nutritional source. Different explants (hypocotyls, cotyledon, root) were used to check the regeneration of both local cotton plants and wild relatives using T & G medium, BAP medium, CIM medium, EMMS medium, and cell suspension medium. Different stages of embryogenicity such as early torpedo stage, late torpedo stage, heart stage, globular stage and cotyledonary stage were observed in wild relatives of cotton. The results of this study pave the way for establishing future transformation methods.
2,4-Dichlorophenoxyacetic Acid ; Benzyl Compounds ; Cotyledon ; growth & development ; Culture Media ; Gossypium ; embryology ; genetics ; growth & development ; metabolism ; Hypocotyl ; growth & development ; Kinetin ; Naphthaleneacetic Acids ; Plant Growth Regulators ; Purines ; Regeneration ; physiology ; Transformation, Genetic ; Zeatin