• Journal of Preventive Medicine and Public Health
• /
• v.16 no.1
• /
• pp.67-77
• /
• 1983

To investigate the an air pollution by particulate matter and its dispersion, a cement plant produceing portland cement 600,000 ton/year and its vicinity were surveyed from Obtober, 1980 to April, 1983. The survey was mainly focused on main stack emmission rate of the cement plant and particle size distribution in the dust, dustfall and total suspended particulate concentration in the area by month and distance from the stack. The results of the study were as follows; 1. The main stack emission rate was surveyed before and after the spray tower was additionally installed to the original E.P bag filter. Before the spray tower installed, the main stack emission rate was higher ($0.64g/Nm^3$) than the emission standard of Korean Environmental Preservation Law's ($0.59g/Nm^3$, amended to $0.4g/Nm^3$ on April 1983), but after the spray tower was installed, its main stack emission rate was markedly decreased to the standard ($0.43g/Nm^3$). 2. $2{\sim}3{\mu}m$ of the particle size was the largest portion (20.8%) of the dust particulate from the main stack and 50% of the frequency distribution was $1.5{\mu}m$ of the size. Most particle size was below $10{\mu}m$. 3. The spray tower reduced the dustfall to $37.81{\sim}9.76\;ton/km^2/month$ while dustfall appeared at $45.29-15.45ton/km^2/month$, in the vicinity of plant before spray tower installed 4. Mean concentrations of total suspended particulate for 24 hours of the various stations were determined in $20.6-200.0{\mu}g/m^3$, 3 stations of tham were higher than the value of Harry and William's arthmetic average standard $130{\mu}g/m^3$. 5. Linear regression between dustfall [X] and total suspended particulate[Y] concentration was an equation, Y=4.024X+11.479.[r=0.91] 6. During the whole seasons in the opposite area 100m apart from the omission source the prevailing wind direction was with estimated more than $30ton/km^2/month$, and the concentration of total suspended particulate for 24 hours averaging time was more than $140{\mu}g/m^3$ in the same area and direction. 7. Assuming the wind direction were constant through the day dustfalls for a day were estimated at $13.40ton/km^2/day,\;10.79ton/km^2/day$ and $4.55ton/km^2/day$ at various distances of 100m, 500m and 1,500m from the emission source respectively. 8. In the simutalion of dustfall and suspended dust by area, Gaussian dispersion model modified by size distribution of particulate matter was not applicated since the emission of dust were from multi sources other them stack. From the above results, it could be applied that the dispersion of dust from the cement plant is estimated and regulated for the purpose of environmental protection.

• The Korean Journal of Nuclear Medicine
• /
• v.24 no.1
• /
• pp.74-79
• /
• 1990

$^{99m}Tc-MAG_3$ was synthesized, and biodistribution and blood clearance rate were compared with those of $^{131}I-OIH$ in mice and rats respectively. Finally renal image was obtained from a normal male volunteer before and after prescription of probenecid. The results obtained were as follows: 1) The uptake of $^{99m}Tc-MAG_3$ by kindey was higher than that of $^{131}I-OIH$ in mice 10 mins after injection (n=6, p<0.05), but slightly lower uptakes were found in all organs (kindney, blood, stomach, intestinge and liver) 2 hrs after injection. 2) For $^{99m}Tc-MAG_3$ $4\frac{1}{2}\;\alpha=2.4{\pm}0.0\;min,\;t\frac{1}{2}\;\beta=44.3{\pm}7.4\;min$, and blood clearance=$3.4{\pm}0.5ml/min$, and for $^{131}I-OIH\;t\frac{1}{2}\;\alpha=1.8{\pm}0.2\;min,\;\beta=69.1{\pm}9.5\;min$, and blood clearance=$1.3{\pm}0.1\;min$ were found in rats. 3) From the renogram of normal male volunteer, we could find that tmax=130 sec and $t\frac{1}{2}=430\;sec$ before probenecid prescription, and $tmax=150\sim170$ sec and $t\frac{1}{2}=810\sim1,170$ sec after probenecid prescriprion. From these results we concluded that $^{99m}Tc-MAG_3$ can be used instead of $^{131}I-OIH$ for obtaining renal image.

• Food Science and Preservation
• /
• v.14 no.2
• /
• pp.124-130
• /
• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• Journal of The Korean Astronomical Society
• /
• v.55 no.4
• /
• pp.123-130
• /
• 2022

We present the analysis of a planetary microlensing event OGLE-2019-BLG-0362 with a shortduration anomaly (~0.4 days) near the peak of the light curve, which is caused by the resonant caustic. The event has a severe degeneracy with ∆𝜒² = 0.9 between the close and the wide binary lens models both with planet-host mass ratio q ≃ 0.007. We measure the angular Einstein radius but not the microlens parallax, and thus we perform a Bayesian analysis to estimate the physical parameters of the lens. We find that the OGLE-2019-BLG-0362L system is a super-Jovian-mass planet $M_p=3.26^{+0.83}_{-0.58}M_J $ orbiting an M dwarf $M_h=0.42^{+0.34}_{-0.23}M_{\odot}$ at a distance $D_L=5.83^{+1.04}_{-1.55}kpc$. The projected star-planet separation is ${\alpha}_{\bot}= 2.18^{+0.58}_{-0.72}AU$, which indicates that the planet lies beyond the snow line of the host star.

• Proceedings of the KSAR Conference
• /
• 2001.03a
• /
• pp.30-30
• /
• 2001

The culture of preantral follicles has important biotechnological implications through its potential to produce the large quantity of oocytes for embryo production, transgenesis research, conservation of rare breed, and a potential source of ovarian genetic material. The present study was conducted to establish the optimal conditions of in vitro culture for intact bovine preantral follicles; and to examine the developmental ability of oocytes derived from the in vitro-grown preantral follicles; and to investigate the effects of various concentrations of FSH and LH on these processes. Bovine preantral follicles (150 $\pm$ 1.2${\mu}{\textrm}{m}$), surrounded by theca cell, were isolated enzymetically and mechanically from ovarian cortical slides in Leibovitz L-15 medium containing 1 mg/$m\ell$ collagens and 0.2 mg/$m\ell$ DNase I and cultured for 25 days in the presence of different concentrations of bovine FSH and LH in $\alpha$MEM medium with insulin, transferrin, and selenite. The survival was tested by frypan Blue and Hematoxylin. The survival and growth rates of follicles were higher in FSH treatment groups than these in control (P<0.001), but there were no significant differences between the LH treatment groups and the control. In 25 days, the survival and growth rates of follicles in FSH and LH treatment group (50%, 300$\pm$1.0${\mu}{\textrm}{m}$) were higher than in FSH treatment group (40%, 244$\pm$0.5${\mu}{\textrm}{m}$) and the control group (25%, 160$\pm$ 1.0${\mu}{\textrm}{m}$). Fifty-five percent of healthy antral follicles were obtained, and 60% of the oocytes complete meiotic maturation to the metaphase II stage. Twenty-two percent of the mature oocytes underwent cleavage, and 9% developed to the blastocyst stage. In this study, in vitro-grown oocytes (111 $\pm$ $1.5mutextrm{m}$), under our culture conditions, were not equivalent in size to the in vivo-grown oocytes (130$\pm$1.3${\mu}{\textrm}{m}$). Therefore, these results suggest that bovine preantral follicles with intact theca cell can grow to the antral stage in 25days, and that oocytes from those follicles can acquire the meiotic competence and normally undergo fertilization and development to the blastocyst stage. However, the developmental capacity of in vitro-grown oocytes is presumably not comparable to those of the in vivo counterparts.

• Molecules and Cells
• /
• v.46 no.9
• /
• pp.545-557
• /
• 2023

Sphingomyelinase (SMase) catalyzes ceramide production from sphingomyelin. Ceramides are critical in cellular responses such as apoptosis. They enhance mitochondrial outer membrane permeabilization (MOMP) through self-assembly in the mitochondrial outer membrane to form channels that release cytochrome c from intermembrane space (IMS) into the cytosol, triggering caspase-9 activation. However, the SMase involved in MOMP is yet to be identified. Here, we identified a mitochondrial Mg²⁺-independent SMase (mt-iSMase) from rat brain, which was purified 6,130-fold using a Percoll gradient, pulled down with biotinylated sphingomyelin, and subjected to Mono Q anion exchange. A single peak of mt-iSMase activity was eluted at a molecular mass of approximately 65 kDa using Superose 6 gel filtration. The purified enzyme showed optimal activity at pH of 6.5 and was inhibited by dithiothreitol and Mg²⁺, Mn²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Fe²⁺, and Fe³⁺ ions. It was also inhibited by GW4869, which is a non-competitive inhibitor of Mg²⁺-dependent neutral SMase 2 (encoded by SMPD3), that protects against cytochrome c release-mediated cell death. Subfractionation experiments showed that mt-iSMase localizes in the IMS of the mitochondria, implying that mt-iSMase may play a critical role in generating ceramides for MOMP, cytochrome c release, and apoptosis. These data suggest that the purified enzyme in this study is a novel SMase.

• Journal of Korean Foot and Ankle Society
• /
• v.27 no.4
• /
• pp.123-130
• /
• 2023

Purpose: "Hallux valgus" is a common disease encountered in clinical practice and is accompanied by foot deformities. Conservative treatment is commonly used in the early stages of hallux valgus. On the other hand, surgical treatment often becomes necessary as the deformity progresses. Surgical treatments involve various osteotomy methods or joint fusion procedures combined with soft tissue release, and outcomes from these surgical treatments are generally favorable. This study compared two soft tissue release techniques in the hallux region. Materials and Methods: This study conducted a retrospective cohort study on 48 participants who underwent surgical treatment for hallux valgus at a single institution from March 1, 2018, to March 31, 2023. A scarf osteotomy was performed in all cases, and the "Modified Mcbride procedure" or "Trans-articular approach" was done for soft tissue release. Hallux valgus angle (HVA), intermetatarsal angle (IMA), and the degree of subluxation of the lateral sesamoid were measured through simple foot radiographs taken before surgery and one year after surgery. Results: In the Modified Mcbride procedure group, HVA, IMA, and the sesamoid position grade decreased from 34.94° to 9.98°, 15.64° to 5.44°, and 2.47 to 0.44, respectively. In the trans-articular approach group, HVA, IMA, and the sesamoid position grade decreased from 33.42° to 7.34°, 15.06° to 6.03°, and 2.17 to 0.58, respectively. There was no significant difference in these changes between the preoperative and one-year postoperative measurements for both techniques (p-value>0.05). Conclusion: A radiological assessment of soft tissue release through the Modified Mcbride procedure and trans-articular approach in hallux valgus did not show significant differences. Therefore, both surgical techniques can be considered in the distal soft tissue release for a hallux valgus correction.

• Korean Journal of Radiology
• /
• v.24 no.4
• /
• pp.338-348
• /
• 2023

Objective: Patients with a history of ischemic stroke are at risk for a second ischemic stroke. This study aimed to investigate the relationship between carotid plaque enhancement on perfluorobutane microbubble contrast-enhanced ultrasonography (CEUS) and future recurrent stroke, and to determine whether plaque enhancement can contribute to risk assessment for recurrent stroke compared with the Essen Stroke Risk Score (ESRS). Materials and Methods: This prospective study screened 151 patients with recent ischemic stroke and carotid atherosclerotic plaques at our hospital between August 2020 and December 2020. A total of 149 eligible patients underwent carotid CEUS, and 130 patients who were followed up for 15-27 months or until stroke recurrence were analyzed. Plaque enhancement on CEUS was investigated as a possible risk factor for stroke recurrence and as a possible adjunct to ESRS. Results: During follow-up, 25 patients (19.2%) experienced recurrent stroke. Patients with plaque enhancement on CEUS had an increased risk of stroke recurrence events (22/73, 30.1%) compared to those without plaque enhancement (3/57, 5.3%), with an adjusted hazard ratio (HR) of 38.264 (95% confidence interval [CI]:14.975-97.767; P < 0.001) according to a multivariable Cox proportional hazards model analysis, indicating that the presence of carotid plaque enhancement was a significant independent predictor of recurrent stroke. When plaque enhancement was added to the ESRS, the HR for stroke recurrence in the high-risk group compared to that in the low-risk group (2.188; 95% CI, 0.025-3.388) was greater than that of the ESRS alone (1.706; 95% CI, 0.810-9.014). A net of 32.0% of the recurrence group was reclassified upward appropriately by the addition of plaque enhancement to the ESRS. Conclusion: Carotid plaque enhancement was a significant and independent predictor of stroke recurrence in patients with ischemic stroke. Furthermore, the addition of plaque enhancement improved the risk stratification capability of the ESRS.

• Childhood Kidney Diseases
• /
• v.3 no.2
• /
• pp.130-144
• /
• 1999

Purpose : Long-term use of Cyclosporine(CsA) reduce renal blood flow by afferent arteriolar vasoconstriction and lead to chronic pathologic changes of CsA nephrotoxicity - 1) interstitial nephritis(IN); tubular atrophy (TA) and/or interstitial fibrosis(IF),2) arteriolopathy(AP). The Object of this study is to estimate the incidence of chronic pathologic CsA nephrotoxicity by duration of treatment and type of renal disease, relationship between histologic and clinical nephrotoxicity, and optimal duration of CsA therapy. Methods : 102 children with steroid resistant or dependent nephrotic syndrome confirmed by renal biopsy and treated with CsA from 1986 to 1997 were enrolled in this study(58 MCNS, 10 FSGS, 10 MGN, 15 $Henoch-Sch\"{o}nlein$ purpura nephritis with nephrotic syndrome (HSPN) and 9 IgA nephropathy with nephrotic syndrome(IgAN)). CsA was administered for 1yr, 1.5yr, 2yr in 24, 12, 22 MCNS patients and 2, 2, 6 FSGS patients respectively, 1yr, 2yr in MGN and 1yr in HSPN and IgAN. Sequential biopsies were done in all 102 patients after CsA treatment for evaluation of pathologic nephrotoxicity. Results : Complete remission rate was 92.2% (100% in MCNS and MGN, 80% in FSGS, 86.6% in HSPN and 55.5% in IgAN). Incidence of relapse during 6months after CsA treatment was significantly decreased compaed with relapsing spisodes during 6months before CsA treatment in MCNS(P<0.0001) and FSGS(P<0.0001). According to pathologic changes, 71 patients(69.6%) showed no pathological change, 24 patients(23.5%) showed IN and 7 patients(6.8%) showed AP. IN was 16.6%, 33.3%, 27.2% in 1, 1.5, 2 year of CsA treatment group in MCNS. AP was 0%, 16.6%, 9% in 1, 1.5, 2 year of CsA treatment group in MCNS. 14 out of 58 MCNS(24.1%) showed IN and 4 out of 58 MCNS(6.8%) showed AP. Incidence of pathologic change was significantly lower in CsA therapy of <1yr than >1yr(P=0.03). There were no significant difference of incidence of pathologic change in original renal disease, age and sex. Conclusion : Duration of CsA treatment was significant risk factor for nephrotoxicity and optimal duration seemed to be 1 year. Pathologic change due to nephrotoxicity did not correlate with deterioration of renal function and only detectable by renal biopsy.

• Clinical and Experimental Pediatrics
• /
• v.50 no.6
• /
• pp.549-555
• /
• 2007

Purpose : Pulse wave velocity (PWV) and ankle brachial index (ABI) are simple, non-invasive methods to assess arterial stiffness. These parameters are also known to be closely related to cardiovascular risk factors and diseases. The purposes of this study were to measure blood pressure, PWV, ABI in healthy Korean adolescents, set up their normal values and assess their correlations. Methods : Three hundred ninety two healthy adolescents (213 boys and 179 girls) underwent measurement of brachial ankle pulse wave velocity (baPWV), ABI, body mass index(BMI) and blood pressure from four extremities. Linear regression analysis was performed to reveal the correlations between PWV, ABI and independent variables. Results : Blood pressure and PWV were significantly higher in all extremities in males compared to females. Blood pressure of both brachial and ankle showed positive correlation with body weight, height, and BMI, whereas ABI showed no correlation with any of these indices. Conclusion : Blood pressure increases as body weight, height and BMI increases. PWV shows positive correlation with blood pressure. It will be helpful to predict the risks of cardiovascular diseases in adolescents.