• Title/Summary/Keyword: Exposure Rates

Search Result 682, Processing Time 0.028 seconds

Response of Ozone Sensitivity in Open-Pollinated Families of Pinus densiflora Seedlings (소나무 풍매차대묘(風媒次代苗)의 가계간(家系間) 오존에 대한 민감성(敏感性) 반응(反應))

  • Lee, Jae-Cheon;Oh, Chang-Young;Han, Sim-Hee;Kim, Jang-Su
    • Journal of Korean Society of Forest Science
    • /
    • v.94 no.3 s.160
    • /
    • pp.191-196
    • /
    • 2005
  • This studies were conducted to compare ozone sensitivity among half-sib families of Japanese red pine (Pinus densiflora S. et Z.). 90 families were exposed in walk-in type chambers to charcoal-filtered air and 100 ppb ozone for 8 hours daily, 5 consecutive months. We surveyed the foliar injury, Relative DRC (diameter at root collar) growth and relative dry weight after fumigation. After 5 months of exposure, foliar injury ranged from 1.9% at tolerant group to 15.2% at sensitive group. Relative DRC growth rates showed increased 12% at tolerant group, but reduced 23% at sensitive group. Total dry weight increased 17% at tolerant group, otherwise reduced by 33% at sensitive group, relative to the control. The root biomass showed more sensitive than the other part biomass. On the basis of the results of these screening studies, families Kangwon 04, 16, 26, 27 and 73 were determined to be tolerant; Kangwon 40, 52, 83, Gyeonggi 01 and Gyeongbuk 20 to be sensitive to ozone. Considerable genetic variation in ozone responses occurred, as shown by differences in sensitivities among families and among groups. These results indicate that tolerant groups of P. densiflora exhibited a high degree of resistance to ozone pollution injury.

Eco-physiological Responses of Two Populus deltoides Clones to Ozone

  • Yun, Sung-Chul;Kim, Pan-Ki;Hur, Jae-Seoun;Lee, Jae-Cheon;Park, Eun-Woo
    • The Korean Journal of Ecology
    • /
    • v.24 no.2
    • /
    • pp.93-100
    • /
    • 2001
  • One-year-old cottonwood (Populus deltoides Bartr.) clones, which were classified as sensitive or tolerant, were exposed to 150 n1/1 ozone (O$_3$) over 8 days for 8 hours each day under glass chamber conditions with natural sunlight. The leaves of the sensitive clone had black stipple and bifacial necrosis after $O_3$ treatment. Photosynthesis and stomatal conductance were measured before, during, and after the $O_3$ treatment. The photosynthetic rates due to $O_3$ treatment were decreased 51 percent and 34 percent on the sensitive and tolerant clone, respectively. The stomatal conductance of the sensitive clone was more than 40 percent higher than that of the tolerant clone regardless of the $O_3$ treatment. As light intensity increased, the $O_3$ effect on photosynthesis was clear. Compared to the previous growth chamber studies, our natural light exposure system was able to maintain a stable photosynthetic responses of the control treatment throughout the fumigation period. In addition, changes in assimilation versus intercellular $CO_2$ concentration (A/C curves) showed that $O_3$ decreased the slope and asymptote of the curves for the sensitive clone. This indicates that $O_3$ decreases the biochemical capacity of photosynthesis on the sensitive clone. Chlorophyll contents and fluorescence of the two clones were analyzed to examine the $O_3$ effects on photosystem 11, but $O_3$ did not impact these variables on either clone. Although the tolerant clone did not show any foliar injury, we could not find any ecophysiological defensive responses to $O_3$ treated. Stomatal conductance of the tolerant clone was originally much lower than that of the sensitive one. Thus, the mechanisms of the tolerant clone in this system are to narrowly open stomata and efficiently maintain photosynthesis with a more durable biochemical apparatus of photosynthesis under $O_3$ stress. The sensitive clone has higher photosynthetic capacity and more efficient light reaction activity than the tolerant one under charcoal filtered condition, but is not as resilient under stress.

  • PDF

Tardive Dyskinesia and Tardive Dystonia with Second-Generation Antipsychotics in Bipolar Disorder Patients Unexposed to First-Generation Antipsychotics (양극성 장애 환자에서 비정형 항정신병약물 치료 후에 나타나는 지연성 운동장애와 지연성 근긴장이상의 유병률 및 위험요인)

  • Lee, Ahram;Kim, Joo Hyun;Baek, Ji Hyun;Kim, Ji Sun;Choi, Mi Ji;Yoon, Se Chang;Ha, Kyooseob;Hong, Kyung Sue
    • Korean Journal of Biological Psychiatry
    • /
    • v.22 no.4
    • /
    • pp.155-162
    • /
    • 2015
  • Objectives Second-generation antipsychotics (SGAs) are frequently used in the treatment of bipolar disorder. However, there is still no consensus on their risk of tardive movement syndromes especially for first-generation antipsychotics (FGAs)-naïve patients. This study aimed to investigate the prevalence and associated factors of SGAs-related tardive dyskinesia and tardive dystonia in patients with bipolar disorder, in a naturalistic out-patient clinical setting. Methods The authors assessed 78 non-elderly patients with bipolar (n = 71) or schizoaffective disorder (n = 7) who received SGAs with a combined use of mood stabilizers for more than three months without previous exposure to FGAs. Multiple direct assessments were performed and hospital records longer than one recent year describing any observed tardive movement symptoms were also reviewed. Results The prevalence rates of tardive dyskinesia and tardive dystonia were 7.7% and 6.4%, respectively. These patients were being treated with ziprasidone, risperidone, olanzapine, quetiapine, or paliperidone at the time of the onset of the movement symptoms. Tardive dyskinesia was mostly observed in the orolingual area, and tardive dystonia was most frequently detected in oromandibular area. A past history of acute dystonia was significantly associated with presence of both tardive movement syndromes. Conclusions Our findings suggest that SGAs-related tardive movement syndromes occur in a substantial portion of bipolar disorder patients. Acute dystonia, a reported risk factor of tardive movement syndromes in the era of FGAs is confirmed as a risk factor of both tardive dyskinesia and tardive dystonia that were induced-by SGAs.

Clinical Significance of Interferon $\gamma$ Release Assay for Diagnosis of Tuberculosis in Children (소아 결핵 진단에 있어서 결핵 특이항원자극 인터페론 감마 측정검사의 임상적 의의)

  • Lee, Hee Woo;Park, Hwa Young;Ahn, Young Min;Sohn, Keun Chan
    • Pediatric Infection and Vaccine
    • /
    • v.17 no.2
    • /
    • pp.137-147
    • /
    • 2010
  • Purpose : The purpose of this study is to evaluate the usefulness and limitation of QuantiFERON-TB Gold (QTB) for diagnosis of latent tuberculosis in children. Methods : The medical records of 112 children who were tested by tuberculin skin test (TST) and QTB for detection of latent tuberculosis (TB) in Eulji General Hospital during the period from January 2007 to June 2009 were retrospectively reviewed. Results : Of the 112 participants, the clinical TB group included 15 (13.4%), the contact group included 43 (38.4%), and the non-contact group included 54 (48.2%). Positive rates of TST and QTB were 100% and 80% in the clinical TB group, 64% and 14% in the close contact group, 27% and 0% in the casual contact group, and 52% and 2% in the non-contact group, respectively. Sensitivity of QTB was 80.0% and specificity was 92.6%. Agreement between QTB and TST was poor ($\kappa$=0.209). We also confirmed that the positive rate of QTB increased as the age of the patient increased (P=0.011). A QTB indeterminate result was observed in 11 (9.8%) subjects. QTB was retested in 15 subjects. In 5 of the 6 subjects who had positive results initially, positive results persisted for a median 2.2 months after termination of treatment. Conclusion : Although QTB was associated with several problems, including low sensitivity and a high rate of indeterminate results, it had clinical importance due to its high specificity. We found good correlation with regard to exposure and QTB positivity, including that of young children under 5 years of age. However, clinical application of interferon-$\gamma$ releasing assay for young children for diagnosis of active and latent tuberculosis will require additional prospective studies.

Effect of Co-Culture with Mammalian Spermatozoa on Maturation in vitro of Porcine Cumulus-Free Germinal Vesicle Oocytes (난구세포가 제거된 돼지 미성숙 난자의 체외성숙에 포유동물 정자가 미치는 영향)

  • Kim, Byung-Ki;Kang, Sung-Ryoung;Yim, Cha-Ok;Han, Chang-Hee;Lee, Bok-Kyu;Lee, Kwang-Sun
    • Journal of Life Science
    • /
    • v.13 no.5
    • /
    • pp.732-739
    • /
    • 2003
  • The purpose of this study was to determine if the addition of spermatozoa into the culture medium could influence the nuclear maturation of denuded porcine germinal vesicle (GV) oocytes in vitro. Cumulus-oocyte complexes were collected from follicles of 3 to 5 mm in diameter, The cumulus and corona cells were removed from oocytes. Porcine denuded oocytes were cultured in tissue culture medium containing spermatozoa. After 48 h culture, oocytes were examined for the evidence of GV breakdown, metaphase I, anaphase-telophase I, and metaphase II (M II). The proportion of oocytes reaching M II stage was significantly (P<0.01) increased in the oocytes cultured in media containing spermatozoa compared to those in media without spermatozoa $(31.9\pm1.8%\; vs\; 14.9\pm1.0%)$.No differences in the rates of M II were observed among the different period of spermatozoa exposure nor among the spermatozoa from different species. The proportion of oocytes reaching M II stage was significantly different between high and low concentrations of spermatozoa. The present study suggests that mammalian spermatozoa contain a substance(s) that improves nuclear maturation in vitro of GV oocytes. Enhancing effect of spermatozoa for oocytes maturation in vitro is a highly dose-dependent.

Study on Epidermal Growth Factor (EGF) and Expression of EGF-Receptor (EGF-R) in Mouse IVF/IVC Embryo;II. Expression of EGF-R on the Inner Cell Mass (ICM) of Mouse IVF/IVC Blastocyst (체외생산된 생쥐배에 대한 EGF와 EGF-R 발현에 관한 연구;II. 체외생산된 생쥐 배반포기배 ICM세포에서의 EGF-R 발현)

  • Kim, E.Y.;Kim, M.K.;Yoon, S.H.;Park, S.P.;Chung, K.S.;Lim, J.H.
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.24 no.1
    • /
    • pp.21-26
    • /
    • 1997
  • This study was undertaken to examine the expression of EGF-R protein on ICM obtained from mouse IVF/IVC blastocyst by immunosurgery and indirect immunofluorescence(IIF). ICM cells used for this experiment were obtained from immunosurgery of mouse blatstocysts produced at 96 h after IVF, and recovered ICMs were assayed for cell viability and expression of EGF-R. The results obtained in this experiment were summarized as follows: when blastocysts were exposed to rabbit anti-mouse serum (antiserum) for 15-30 min. and then transferred them to guinea pig serum (complement) for 15-60 min., recovery rates of isolated ICMs were 8.0-84.2%. Especially, the best recovery (84.2%) of ICMs was obtained when exposure time to antiserum and complement was 30 min. and 60 min., respectively. In addition, when viability of isolated ICMs after immunosurgery was assessed by live/dead staining method, in all groups viability (93.8-100.0%) of isolated ICMs were not damaged if separated from TE cell. Also, we detected the expression of EGF-R on ICM cell by IIF. Therefore, these results suggest that EGF-R expression on the ICMs can stimulate the higher usablity of exogenous EGF to improve the preimplantation embryo development in vitro.

  • PDF

Arsenic Toxicity on Duck Spermatozoa and the Ameliorating Effect of L-Ascorbic Acid

  • Lin, Chai-Ching;Huang, Chia-Cherng;Chen, Ming-Cheng;Huang, Andrew Jeng-Fang;Chiou, Hung-Yi
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.1
    • /
    • pp.19-25
    • /
    • 2002
  • The objectives of this study were to understand the possible mechanism of duck sperm toxicity induced by arsenic exposure in vivo, and to investigate the roles of the antioxidant L-ascorbic acid in ameliorating the arsenic-induced sperm impairment. To test the acute toxicity, the percentages of mortality of mature drakes treated with different concentrations of trivalent sodium arsenite, As (III), and pentavalent sodium arsenate, As (V) were measured. The LD50 value of As (III) for mature drakes was $4.89{\pm}1.49$ ppm. Although As (V) didn't cause any deaths even at a concentration of 40 ppm, the chronic toxicity of As (V) on sperm quality was shown by a decreased fertilization rate. When the concentrations of As (V) were above 0.4 ppm, fertilization rates were lower than those of 0.04 ppm and control. Drakes treated with 40 ppm of As (V) had the highest malondialdehyde (MDA) level in the testis tissue, $3.100{\pm}0.218{\mu}mole/g$ testis. This showed that 40 ppm of As (V) significantly induced lipid peroxidation in testis tissue. For the 1.2 ppm As (III) treatment, several significant effects were observed: (1) sperm motility was decreased most dramatically by $52.0{\pm}9.1$% after three days of incubation; (2) fertilization rate of artificially inseminated semen was the lowest, $26.4{\pm}15.4$; (3) the MDA concentration in testis tissue, $7.846{\pm}0.246{\mu}mole/g$ testis, was significantly higher than the others (p<0.05); (4) the sperm number, $1.17{\pm}0.40({\times}10^9)$, was significantly lower than with the 60 ppb and control treatments (p<0.05); (5) a black appearance and soft texture was observed in the testis tissue. The antioxidant L-ascorbic acid administered along with 1.2 ppm As (III) decreased the toxicity of arsenic. The ameliorating effects included: improved sperm motility, increased sperm number and fertilization rate, and decreased MDA concentration in the testis tissue. This study suggests that the toxicity of the trivalent arsenic on sperm quality is partly from free radicals generated by its metabolic pathway, and the antioxidant ascorbic acid ameliorates arsenic-caused sperm impairment.

Correction of Recurrent Ingrowing Toenail Using Partial Matricectomy and Paronychial Advancement Flap (부분기질절제술과 발톱주위전진피판을 이용한 재발성 내증식발톱의 교정)

  • Kim, Eui Sik;Kim, Sung Nam;Noh, Bok Kyun;Hwang, Jae Ha;Kim, Kwang Seog;Lee, Sam Yong
    • Archives of Plastic Surgery
    • /
    • v.33 no.3
    • /
    • pp.347-352
    • /
    • 2006
  • Ingrowing toenail has been treated conventionally by various surgical treatment modlities. However, none of these procedures are perfect to achieve esthetic results with low cost, recurrence, and complication rates. Although mild cases can be treated conservatively, in severe recurrent cases, surgical treatment is preferred. The purpose of this study is to evaluate the effectiveness and safety of using partial matricectomy and paronychial advancement flap for correction of recurrent ingrowing toenail. Eight patients suffering from recurrent ingrowing toenail were operated using partial matricectomy and paronychial advancement flap in our department from August 2004 to August 2005. The number of recurrent episodes ranged from 2 to 5. With digital nerve block, the excision area was marked on nailplate and inflammed lateral nail fold. The horizontally designed paronychial flap considering defect size was effective for wide exposure of the neighboring germinal matrix, which is later to be completely excised or cauterized because remnant germinal matrix made postoperative spicule formation. The nailplate on the affected side was removed about 3-5 mm width longitudinally, being cautious not to damage the proximal dorsal nail fold. The same width of the sterile matrix including germinal matrix was excised longitudinally with inflammed granulation tissue and partial lateral nail fold on the affected side. The subcutaneously elevated paronychial flap was advanced to cover the defect and was anatomically sutured with 5-0 nylon sutures. We evaluated our procedure's effectiveness by examining some factors such as cosmetic results, recurrence, spicule formation, postoperative pain and duration of return to normal activities. In eight patients, no complication was observed such as recurrence, severe pain and spicule formation except for 1 case of infection. Postoperative discomfort was minimal. Average duration of return to normal activities was 12 days. Cosmetically the results were acceptable in all patients. The partial matricectomy and paronychial advancement flap for correction of recurrent ingrowing toenail were found to be technically simple, efficient procedure with a relative low recurrence rate and better cosmetic results.

Field Study of Emission Characteristics of Ammonia and Hydrogen Sulfide by Pig Building Types (돈사 작업장 유형에 따른 암모니아와 황화수소의 실내농도 및 발생량에 관한 현장 조사)

  • Kim, Ki Youn;Park, Jae Beom;Kim, Chi-Nyon;Lee, Kyung Jong
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.16 no.1
    • /
    • pp.36-43
    • /
    • 2006
  • The principal aim of this field study was to determine the concentrations and emissions of gaseous contaminants such as ammonia and hydrogen sulfide in the different types of pig buildings in Korea and allow objective comparison between Korea and the other countries in terms of pig housing types. This field study was performed from May to June and from September to October in 2002. Pig buildings investigated in this research were selected in terms of three criteria; manure removal system, ventilation mode and growth stage of pig. Measurements of concentration and emission of ammonia and hydrogen sulfide in the pig buildings were done in 5 housing types and the visited farms were 15 sites per each housing type. Concentrations of ammonia and hydrogen sulfide were measured at three locations of the central alley in the pig building and emission rates of them were estimated by multiplying the average concentration($mg/m^3$) measured near the air outlet by the mean ventilation rate($m^3/h$) and expressed either per pig of liveweight 75kg(mg/h/pig) or per area($mg/h/m^2$). Concentrations of ammonia and hydrogen sulfide in the pig buildings were averaged to 7.5 ppm and 286.5 ppb and ranged from 0.8 to 21.4 ppm and from 45.8 to 1,235 ppb, respectively. The highest concentrations of ammonia and hydrogen sulfide were found in the mechanically ventilated buildings with slats; 12.1 ppm and 612.8 ppb, while the lowest concentrations of ammonia and hydrogen sulfide were found in the pig buildings with deep-litter bed system(2.2 ppm) and the naturally ventilated pig buildings with manure removal system by scraper(115.2 ppb), respectively(p<0.05). All the pig buildings were investigated not to exceed the threshold limit values(TLVs) of ammonia(25 ppm) and hydrogen sulfide(10 ppm). The mean emissions of ammonia and hydrogen sulfide per pig(75kg in terms of liveweight) and area($m^2$) from pig buildings were 250.2 mg/h/pig and 37.8 mg/h/pig and $336.3mg/h/m^2$ and $50.9mg/h/m^2$, respectively. The pig buildings with deep-litter bed system showed the lowest emissions of ammonia and hydrogen sulfide(p<0.05). However, the emissions of ammonia and hydrogen sulfide from the other pig buildings were not significantly different(p>0.05). Concentrations and emissions of ammonia and hydrogen sulfide were relatively higher in the pig buildings managed with deep-pit manure system with slats and mechanical ventilation mode than the different pig housing types. In order to prevent pig farm workers from adverse health effect caused by exposure to ammonia and hydrogen sulfide in pig buildings, they should wear the respirators during shift and be educated sustainably for the guideline related to occupational safety.

Epidemiology of Breast Cancer among Females in Basrah

  • Habib, Omran S;Hameed, Lamis A;Ajeel, Narjis A;Al-Hawaz, Mazin H;Al-Faddagh, Zaki A;Nasr, Ghalib N;Al-Sodani, Ali H;Khalaf, Asaad A;Hasson, Hasson M;Abdul-Samad, Aida A
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.sup3
    • /
    • pp.191-195
    • /
    • 2016
  • Breast cancer is the most frequent cancer in females. Its incidence is higher in developed countries than in developing ones partly due to variation in risk exposure and partly due to better detection methods. Scattered evidence in Basrah, Iraq, suggests that breast cancer has been increasing at a significant pace in recent years. This study aimed to measure the current level of risk of breast cancer among females in Basrah and to describe the time trend over almost a decade of years. Data on breast cancer cases from all sources of cancer registration in Basrah governorate were compiled for the years 2005-2012. The data for each year were first checked separately for duplicate reporting of cases among various sources. Then the eight files were pooled together and checked again for any duplicate cases among years of registration. The final set of data contained 2,284 cases of breast cancer (2,213 female cases and 71 male cases). All patients were inhabitants of Basrah governorate at the time of diagnosis. Figures on the Basrah population were obtained from various sources including the Ministry of Health, Ministry of Planning and Developmental Collaboration and local household surveys. It was possible to have total population estimates for each year and by age and sex. The data were imported into SPSS (version 17) software. Age specific and year specific incidence rates were calculated. The age standardized incidence rate was also calculated using world population as the standard population to be 34.9 per 100,000 females. Age-wise, no case was reported among children aged less than 15 years and the incidence increased with advancing age reaching a peak of 123.8/100,000 females at the age range of 50-54 years. The time trend of the crude incidence rate showed only modest increased risk with passage of years and no age shift could be documented in this study. Breast cancer in females in Basrah is a significant health problem. The current incidence rate (crude, 23.7/100,000, age-standardized, 34.9/100,000) is high and justifies intensive efforts to improve early detection of cases, provide better treatment amenities and introduce long term preventive measures. Using the age standardized incidence rate as reported in this paper, it is possible to put the risk in Basrah within a regional and international context.